Connection mode controlling apparatus, connection mode controlling method, and connection mode controlling program

Technical field of connection mode control device, connection mode control method, and connection mode control program

[0001] The present invention relates to the technical field of a network control device, a connection mode control device, a network control method, a connection mode control method, a network control program, and a connection mode control program. More specifically, the present invention relates to a network control device for controlling a distribution mode of distribution information distributed from a distribution source in a network system while gradually relaying the distribution information in relay units connected to form a multi-level hierarchy , The technical field of connection mode control equipment, network control method, connection mode control method, network control program and connection mode control program.

Background technique

[0002] In recent years, with the increase in the speed of Internet lines used in homes, network systems have been widely used. In a network system, a network is constructed by connecting home personal computers and the like into a tree structure with a single distribution device as a distribution source at the apex, and so-called content such as music and movies are distributed via the network from the distribution device as distribution information. From the perspective of the connection mode, the network is called a "topology". Each distribution device and personal computer constituting the network is generally called a "node".

[0003] For example, Patent Document 1 discloses the prior art of a network system.

Patent Document 1: Japanese Patent Pending Publication No. 2003-169089.

[0004] In each node included in the existing network system represented by the network system of Japanese Patent Laid-Open No. 2003-169089, the content transmitted from the upper node is temporarily stored in a buffer memory and used for playback processing Wait. This structure tries to reduce the structure in the network system

200580023946.9 The influence of transmission speed fluctuations in the Internet circuit of the first distribution path. For example, a FIFO (first in first out) memory such as a ring buffer memory is used as the buffer memory.

[0005] On the other hand, in a network system, the node that constructs the system is a home personal computer or the like as described above. Therefore, there may be cases where the power of any node on the distribution path is cut off regardless of whether the content is being distributed. In this case, the function of relaying content to the lower node connected to the node whose power switch is turned off will be stopped.

[0006] During the content distribution in the network system, when the relay function of any node on the distribution path is stopped, the topology is reconstructed to include nodes other than the node whose relay function is stopped (that is, , Rebuild the publishing path from the publishing device to the lower node directly connected to the node where the relay function is stopped and restart publishing).

SUMMARY OF THE INVENTION Problems to be solved by the present invention

[0007] However, in the topology reconstruction of the existing network system, processing such as searching for the shortest path from the publishing system and using the search results for connection switching is necessary. As a result, the distribution of content to lower-level nodes is temporarily interrupted. In the case where the distribution is interrupted, in the lower node, the processing of the playback content stored in the buffer memory is continued (in other words, the data stored in the buffer memory as content is consumed), but the new content is not supplied to buffer. As a result, problems may occur, causing the amount of storage in the buffer to gradually decrease, and in some cases, content playback processing in lower-level nodes is interrupted. .

[0008] In a case where the relay function of any node included in the network system is stopped, interrupting the playback process may cause deterioration of the reliability of the network system itself.

[0009] The implementation of the present invention takes these problems into consideration, and the purpose of the present invention is to propose a network control device, a network control method, and a network control program for controlling the publishing mode in the network system so that even if the network system includes Relay function of any node

In the case of 200580023946.9, the content can be released reliably, and at the same time, the reliability of the network system itself can be improved without affecting the processing in the lower nodes.

The solution to the problem

[0010] In order to achieve this object, the present invention according to claim 1 relates to a network control device for controlling any one of a plurality of repeaters included in the following network system, the network system including as the release information The publisher of the publishing source and a plurality of repeaters connected to the publisher and forming multiple levels, and wherein the publishing information is published from the publisher to each repeater, the device includes:. A detection device such as a CPU is used to detect that in the issuance of the distribution information to the target repeater that is the repeater to be controlled, the repeater is relayed in any one of the repeaters located upstream. Whether the function of posting information is stopped; and a consumption control device such as a CPU for controlling the unit time consumption as the consumption per unit time of the posting information stored in the target repeater to be smaller than The unit time consumption amount before the stop of the relay function, and the release information is consumed due to use in a process executed in the target repeater when the stop of the relay function is detected.

[0011] Therefore, when the relay function in the repeater located on the upstream side in the network system is stopped, the consumption per unit time of the posting information stored in the repeater located on the downstream side is controlled to be less than the stop The previous consumption. As a result, without increasing the burden on the network system itself, it is possible to prevent the processing interruption in the downstream repeater caused by the interruption of the distribution of the posted information and the posted information is still being consumed at a rate similar to that before the interruption. Or serious processing delays occur.

[0012] In order to achieve this object, the present invention as claimed in claim 2 relates to the network control device as claimed in claim 1, wherein the release information is image information, and the consumption control device uses The image information used for processing reduces the storage capacity of the image information in the cache device at a slower rate than the decrease before the relay function stops, so as to reduce the consumption per unit time, wherein the cache device For temporary storage

200580023946.9 The image information in the target repeater.

[0013] Therefore, in addition to the effect of the present invention according to claim 1, the posting information is image information, and by making the reduction speed of the storage amount of image information in the cache device slower than the reduction speed before the relay function is stopped, To reduce the consumption per unit time. Therefore, without performing complicated speed control processing, a simple structure can be adopted to reduce the consumption per unit time.

[0014] In order to achieve this object, the present invention according to claim 3 relates to the network control device according to claim 2, wherein the image information is dynamic image information composed of a plurality of still images, and the consumption control device By repeatedly outputting the same still image from the buffering device multiple times, the reduction speed of the storage amount is reduced:

[0015] Therefore, in addition to the effect of the present invention according to claim 2, the speed of reducing the storage amount is reduced by repeatedly outputting the same still image as the composition of the moving image information multiple times. Therefore, the consumption per unit time can be reliably reduced by simple processing.

[0016] In order to achieve this object, the present invention according to claim 4 relates to the network control device according to claim 1, wherein the distribution information is encoded image information, and the consumption control device The decoding speed of the image information in the processing in the target repeater is slower than the decoding speed before the relay function is stopped, so as to reduce the consumption per unit time.

[0017] Therefore, in addition to the effect of the present invention according to claim 1, the unit time consumption is reduced by making the speed of decoding image information in the processing in the target repeater slower than the decoding speed before the relay function is stopped. Therefore, the consumption per unit time can be reliably reduced by simple processing.

[0018] In order to achieve this object, the present invention according to claim 5 relates to a network control device according to claim 1, wherein the release information is a dynamic image composed of a plurality of still images.

200580023946.9 first image information, and the consumption control device reduces the consumption per unit time by making the display time of the still image longer than the display time before the relay function is stopped.

[0019] Therefore, in addition to the effect of the present invention according to claim 1, the unit time consumption is reduced by making the display time of a still image that is a composition of moving image information longer than the display time before the relay function is stopped. Therefore, the consumption per unit time can be reliably reduced by simple processing.

[0020] In order to achieve this object, the present invention according to claim 6 relates to a network control device according to any one of claims 1 to 5, wherein the release information is composed of a plurality of consecutive unit release information, so If the unit publishing information in the predetermined position in the publishing information is empty, the information volume of the publishing information used for processing is zero, and the device further includes: a reset device such as a CPU, After the issuance of the target repeater restarts, for resetting the unit time consumption in the target repeater to the same unit time consumption as before the relay function is stopped; and The release control device of the CPU, after resetting the unit time consumption in the target repeater, is used to issue empty unit release information to all repeaters except the following repeaters, so The repeater is the repeater located downstream in an announcement before the relay function of the repeater whose relay function is stopped is stopped.

[0021] Therefore, in addition to the effects of the present invention according to any one of claims 1 to 5, only empty cell release information is released to the ones except before the relay function of the relay whose relay function is stopped is stopped. All repeaters other than the repeater located on the downstream side in the release. Therefore, the playback time base in the repeater becomes gradually closer to the playback time base in other repeaters. As a result, by reducing the unit time consumption in the repeater on the downstream side of the repeater whose repeater function is stopped, it is possible to reduce one of the playback positions of the repeater and other repeaters on the playback time base. Between the deviations.

[0022] In order to achieve this object, the present invention as recited in claim 7 relates to a control method for controlling any one of a plurality of repeaters included in the following network system, the network

200580023946.9 The first network system includes a publisher as a publishing source for publishing information and a plurality of repeaters connected to the publisher and forming multiple levels, and wherein the publishing information is published from the publisher to each A relay, the method includes: a detection step for detecting that in the issuance of the release information to the target relay as the relay to be controlled, in any one of the relays located upstream Whether the function of relaying the posted information is stopped; and a consumption control step for controlling the unit time consumption as the consumption per unit time of the posted information stored in the target repeater so that Less than the unit time consumption amount before the stop of the relay function, the release information is consumed due to use in the processing executed in the target repeater when the stop of the relay function is detected.

[0023] Therefore, when the relay function in the repeater located on the upstream side in the network system is stopped, the consumption per unit time of the posting information stored in the repeater located on the downstream side is controlled to be less than The consumption before the stop. As a result, without increasing the burden on the network system itself, it is possible to prevent processing from occurring in downstream repeaters due to the situation where the distribution of the published information is interrupted and the published information is still consumed at a rate similar to that before the interruption. Interruption or severe processing delay.

[0024] In order to achieve this object, the present invention as recited in claim 8 causes a computer included in a network control device to function as follows for controlling a plurality of relays included in the following network system The network system includes a publisher as a publishing source for publishing information, and a plurality of repeaters connected to the publisher and forming multiple levels, and wherein the publishing information is transmitted from the publishing source. The relay is issued to each repeater, and the function is: a detection device for detecting that in the issuance of the publishing information to the target repeater to be controlled, any upstream Whether the function of relaying the posted information in one of the repeaters is stopped; and a consumption control device for controlling the amount of consumption per unit time of the posted information stored in the target repeater The unit time consumption amount is smaller than the unit time consumption amount before the relay function stops, and the release information is due to the processing performed in the target repeater when the relay function stop is detected Use and be consumed.

[0025]

200580023946.9 Therefore, when the relay function in the repeater on the upstream side in the network system stops, the computer functions so that the consumption per unit time of the posted information stored in the repeater on the downstream side becomes Less than the unit time consumption before the relay function stops. Therefore, without increasing the burden on the network system itself, it is possible to prevent the downstream repeater from being processed in the downstream repeater due to the interruption of the release of the released information and the release of the information is still consumed at a rate similar to the one before the interruption. Interruption or severe processing delay.

[0026] In order to achieve this object, the present invention as recited in claim 9 relates to a connection mode control device for controlling a publisher as a publishing source of publishing information in a network system and connecting to the publishing in a tree structure And form a connection mode between multiple relays at multiple levels, wherein the release information is released in the network system, and the equipment includes: a retrieval device such as a CPU, when any one of the relays When the relay function is stopped, it is used to retrieve any one of the relays except the relay whose relay function is stopped and can relay the release information; a connection device such as a CPU is used for Connecting the repeater that receives the posting information to the retrieved another repeater; and a posting continuation device such as a CPU for passing the posting information via the other repeater The publishing speed of is faster than the publishing speed before the relay function is stopped to continue the publishing of the publishing information via the connected relay.

[0027] Therefore, when the relay function in any one of the relays is stopped, another relay that can relay the posted information is searched. When the distribution of the published information is continued via the retrieved another repeater, the publishing speed of the published information is made faster than the publishing speed before the relay function stops. Therefore, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0028] In order to achieve this object, the present invention according to claim 10 relates to the connection mode control device according to claim 9, wherein the release continuation means continues to issue while gradually passing through another repeater of the connection The release speed of the release information is increased to the maximum value of the release speed specified in the network connecting the publisher and each repeater, as an upper limit.

200580023946.9 p.

[0029] Therefore, the distribution is continued while gradually increasing the distribution speed of the distribution information via another connected repeater to the maximum value of the distribution speed as the upper limit, so that the repeaters belonging to a lower level can be faster To get the necessary release information.

[0030] In order to achieve this object, the present invention according to claim 11 relates to a connection mode control device according to claim 9 or 10, wherein the release continuation means works by making the release speed faster than before the relay function is stopped. The distribution is continued at the distribution speed until the storage amount of the distribution information to be distributed in the repeater as the distribution destination becomes a predetermined amount.

[0031] Since the posting is continued by making the posting speed faster than the posting speed before the relay function is stopped, until the storage amount of the posted posting information in the repeater that is the posting destination of the posted posting information becomes predetermined Therefore, it is possible to reliably continue the processing of publishing information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0032] In order to achieve this object, the present invention as recited in claim 12 relates to a connection mode control device for controlling a publisher as a publishing source of publishing information in a network system and connecting to the publishing in a tree structure The connection mode between multiple repeaters and forms multiple levels, wherein the release information is released in the network system, and the equipment includes: a connection device such as a CPU for connecting the multiple Some of the repeaters are connected to one of the repeaters, thereby forming a plurality of paths for distributing the release information to the one repeater; and a release control device such as a CPU for using the via as one of the paths The main path is to publish the release information of the one repeater to another repeater belonging to the level below the one repeater, and to provide the release for the external output processing in the one repeater Information, and publish the published information that is published to the one repeater via the main path as one of the paths or the sub-path of the other path to another one of the levels that belong to the one repeater Repeater.

[0033] Therefore, the main path and the sub-path are formed to connect multiple repeaters to one repeater,

200580023946.9 The release information issued via the main path is used for external output processing in the one repeater, and used for publishing to another repeater belonging to a hierarchy below the one repeater. The release information distributed via the main path or the sub path as one of the paths is also used to distribute to another repeater belonging to a lower level. By connecting multiple lines to each node, redundancy can be increased when preparing to stop the relay function of any one node, and it is possible to prevent the external output processing in the repeater belonging to a lower level from being stopped.

[0034] In order to achieve this object, the present invention according to claim 13 relates to a connection mode control device according to claim 12, further comprising a switching device such as a CPU, when belonging to the one repeater on the main path When the relay function of the repeater of the hierarchical level stops, it is used to switch the posted information that is posted to the one repeater via the sub-path, so as to provide it to the one repeater External output processing.

[0035] Therefore, when the relay function of the repeater belonging to the level above the one repeater on the main path is stopped, it is used to switch the distribution information distributed via the sub path to provide it to the outside Output processing. Therefore, the external output processing in the one repeater will not be interrupted.

[0036] In order to achieve this object, the present invention according to claim 14 relates to a connection mode control device according to claim 13, further comprising retrieval means, which is issued to the one via the sub-path when switched by the switching means When the publishing information of the repeater is provided to the external output processing in the one repeater, it is used to retrieve the publisher or a new medium belonging to the hierarchy above the one repeater. A repeater, wherein the connecting device connects the issuer or the new repeater retrieved by the retrieval device to the one repeater, thereby forming a new path.

[0037] Therefore, when the posted information posted via the sub-path is switched to provide it to the external output processing, the issuer or a new repeater belonging to a hierarchy above the one repeater is retrieved, and the issuer or retrieved The new repeater is connected to the one repeater, thereby forming a new path. Therefore, redundancy can be ensured and maintained.

200580023946.9 p.

[0038] In order to achieve this object, the present invention according to claim 15 relates to a connection mode control device according to claim 12, further comprising retrieval means, when belonging to the one above the repeater on the sub-path When the relay function of the repeater of the hierarchy is stopped, it is used to retrieve the publisher or the new repeater belonging to the hierarchy above the one repeater, wherein the connection device will The publisher or the new repeater retrieved by the retrieval device is connected to the one repeater, thereby forming a new sub-path.

[0039] Therefore, when the relay function of the repeater belonging to the level above the one repeater on the sub-path is stopped, search for the publisher or a new relay belonging to the level above the one repeater And connect the publisher or the retrieved new repeater to the one repeater, thereby forming a new sub-path. Therefore, even when the relay function in the repeater located on the sub-path stops, a new sub-path can be formed, and redundancy can be ensured and maintained.

[0040] In order to achieve this object, the present invention according to claim 16 relates to the connection mode control device according to claim 14 or 15, wherein the retrieval means retrieves the publisher or the new repeater so that the one Another repeater on the hierarchy to which the repeater belongs is included in the new main path.

[0041] Therefore, a publisher or a new repeater is retrieved so that another repeater located on the level to which the one repeater belongs is included in the new main path, so that the repeater on the same level can be passed through To receive post information.

[0042] In order to achieve this object, the present invention according to claim 17 relates to a connection mode control device according to any one of claims 9 to 16, wherein the connection means connects each repeater on a different level to This one repeater thus forms multiple paths.

[0043] Therefore, since repeaters located on different levels are connected to the one repeater, thereby forming multiple paths to the one repeater, even when there is a possibility of a failure such as a stop of the relay function When different at different levels, sufficient redundancy can be reliably ensured.

200580023946.9 remainder.

[0044] In order to achieve this object, the present invention as recited in claim 18 relates to a connection mode control method for controlling a publisher as a publishing source of publishing information in a network system and connecting to the publishing in a tree structure And form a connection mode between multiple relays at multiple levels, wherein the release information is released in the network system, the method includes: a retrieval step, when any one of the relays is in the middle When the function is stopped, search for any one of the repeaters except the repeater whose relay function is stopped and be able to relay the posted information; the connecting step will be used to receive all the posted information. The repeater is connected to the retrieved another repeater; and a post continuation step, as a post connection step for continuing to post the post information via the connected another repeater, is used to pass through the The release speed of the release information of the other repeater is faster than the release speed before the relay function is stopped to continue the release.

[0045] Therefore, when the relay function in any one of the relays is stopped, another relay that can relay the posted information is retrieved. When continuing the publication of the publication information via the retrieved another repeater, the publication speed of the publication information is made faster than the publication speed before the relay function is stopped. Therefore, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0046] In order to achieve this object, the present invention as recited in claim 19 relates to a connection mode control method for controlling a publisher as a publishing source of publishing information in a network system and connecting to the publishing in a tree structure The connection mode between multiple relays at multiple levels and forming multiple levels, wherein the release information is released in the network system, and the method includes: a connecting step, which is used to connect the multiple relays Some of them are connected to one of the repeaters, thereby forming a plurality of paths for distributing the release information to the one repeater; and a release control step for distributing to the main path via the main path as one of the paths The posted information of the one repeater is posted to another repeater belonging to the level below the one repeater, the posted information is provided for the external output processing in the one repeater, and will be used as The main path of one of the paths or as a sub-path of the other path is published to

200580023946.9 The release information of the first repeater is released to another repeater belonging to the level below the repeater.

[0047] Therefore, a main path and a sub-path are formed to connect a plurality of repeaters to one repeater, and the posting information issued via the main path is used for external output processing in the one repeater and used for posting to The posting information that belongs to another repeater of a level below the one repeater and is distributed via the main path or the sub path as one of the paths is also used to distribute to another repeater belonging to a lower level. Therefore, by using multiple lines for repeaters, redundancy can be increased when preparing to stop the repeater function of any one repeater, and it is possible to prevent external output processing in repeaters belonging to a lower level from being Stop.

[0048] In order to achieve this object, the present invention as recited in claim 20 causes a computer included in a control mode control device to function as follows, and the control mode control device is used to control the distribution as distribution information in a network system A connection pattern between a publisher such as a node of a source and a plurality of repeaters such as a plurality of nodes that are connected to the publisher in a tree structure and form multiple levels, wherein the published information is in the network Announced in the system, the function is: a search device, when the relay function of any one of the repeaters is stopped, it is used to search for any one of the relays except the repeater whose relay function is stopped. Relay and capable of relaying the posting information; connecting means for connecting the repeater receiving the posting information to the other retrieved repeater; and posting continuation means as a means for passing through the The distribution continuation means for continuing the distribution of the distribution information by another repeater connected is configured to make the distribution of the distribution information via the other repeater faster than the distribution before the relay function is stopped Speed to continue publishing.

[0049] Therefore, when the relay function of any one of the relays is stopped, another relay that can relay the posted information is searched. When continuing the publication of the published information via the retrieved another repeater, the function of the computer is to continue the publication by making the publication speed of the published information faster than the publication speed before the relay function is stopped. Therefore, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0050]

200580023946.9 First, in order to achieve this object, the present invention as claimed in claim 21 enables a computer included in a connection mode control device to function as follows, and the connection mode control device is used to control the distribution source of the distribution information in the network system The connection mode between the publisher and multiple repeaters connected to the publisher in a tree structure and forming multiple levels, wherein the published information is published in the network system, and the function is: A connecting device for connecting some of the plurality of repeaters to one of the repeaters, thereby forming a plurality of paths for publishing the publishing information to the one repeater; and a publishing control device, It is used to publish the published information that is published to the one repeater via the main path as one of the paths to another repeater belonging to a hierarchy below the one repeater, for the one repeater The external output processing provides the posted information, and releases the posted information that is posted to the one relay via the main path as one of the paths or the sub-path as the other path to the one that belongs to the relay Another repeater on the level below the device.

[0051] Therefore, a main path and a sub-path are formed to connect a plurality of repeaters to one repeater, and the posting information issued via the main path is used for external output processing in the one repeater, and for posting to The posting information that belongs to another repeater of a level below the one repeater and is distributed via the main path or the sub path as one of the paths is also used to distribute to another repeater belonging to a lower level. Therefore, by using multiple lines for repeaters, redundancy can be increased when preparing to stop the repeater function of any one repeater, and it is possible to prevent external output processing in repeaters belonging to a lower level from being Stop.

[0052] According to the invention of claim 1, when the relay function in the repeater located on the upstream side in the network system is stopped, each unit of the posted information stored in the repeater located on the downstream side is controlled Time consumption so that it is less than the consumption before stopping. As a result, without increasing the burden on the network system itself, it is possible to prevent downstream repeaters from being caused by a situation where the distribution of the posted information is interrupted while the posted information is still consumed at a rate similar to that before the interruption. The processing in the system is interrupted or severe processing delay occurs.

[0053] Therefore, even in the case where the relay function in any one of the repeaters included in the network system is stopped, without exerting a large influence on the processing in the downstream repeater,

200580023946.9 The stopped relay function can be restored. Therefore, the released information can be reliably released, and at the same time the reliability of the network system itself is improved.

[0054] In the present invention according to claim 2, in addition to the effects of the present invention of claim 1, the posted information is image information, and the reduction speed of the storage amount of the image information in the cache device is slower than that of the present invention. The reduction rate before the relay function stops can reduce the consumption per unit time. Therefore, a simple structure can be adopted to reduce the consumption per unit time without performing complicated speed control processing.

[0055] In the present invention according to claim 3, in addition to the effect of the present invention of claim 2, the reduction speed of the storage amount is slowed by repeatedly outputting the same still image as a component of the moving image information multiple times. Therefore, simple processing can reliably reduce the consumption per unit time.

[0056] In the present invention according to claim 4, in addition to the effect of the present invention of claim 1, the decoding speed of the image information in the processing in the target repeater is slower than before the relay function is stopped. Decoding speed to reduce unit time consumption. Therefore, simple processing can reliably reduce the consumption per unit time.

[0057] In the invention according to claim 5, in addition to the effect of the invention of claim 1, by making the display time of the still image as a component of the moving image information longer than the display time before the relay function is stopped . Therefore, simple processing can reliably reduce the consumption per unit time.

[0058] According to the present invention of claim 6, in addition to the effects of the present invention of any one of claims 1 to 6, after the relay function is restored, the empty unit release information is released only to other than its relay The relay function of the repeater whose function is stopped stops all the repeaters other than the downstream repeater in the previous release. Therefore, the playback time base in the repeater becomes gradually closer to the playback time base in other repeaters. As a result, by reducing the unit time consumption in the repeater on the downstream side of the repeater whose relay function is stopped, it is possible to eliminate

200580023946.9 The deviation between the playback position on the playback time base of this repeater and the playback positions of other repeaters.

[005] According to the invention of claim 7, when the relay function in the repeater located on the upstream side in the network system is stopped, control the distribution of information stored in the repeater located on the downstream side. The consumption per unit time is smaller than the consumption before the stop. Therefore, without increasing the burden on the network system itself, it is possible to prevent processing in the downstream repeater caused by the interruption of the release of the released information and the release of the information still being consumed at a rate similar to that before the interruption. Interruption or severe processing delay.

[0060] Therefore, even if the relay function of any one of the repeaters included in the network system is stopped, the stopped relay can be resumed without exerting a large influence on the processing of the downstream repeater. Features. Therefore, the released information can be reliably released, and at the same time the reliability of the network system itself is improved.

[0061] According to the present invention described in claim 8, when the relay function in the repeater located on the upstream side is stopped, the computer functions so that the distribution information stored in the repeater located on the downstream side The consumption per unit time is less than the consumption before the relay function stops. Therefore, without increasing the burden on the network system itself, it is possible to prevent the downstream repeater from being processed in the downstream repeater due to the interruption of the release of the released information and the release of the information still being consumed at a rate similar to that before the stop. Interruption or severe processing delay.

[0062] Therefore, even when the relay function of any one of the repeaters included in the network system is stopped, the stopped relay can be resumed without exerting a large influence on the processing of the downstream repeater Features. Therefore, the released information can be reliably released, and at the same time the reliability of the network system itself is improved.

[0063] According to the invention described in claim 9, when the relay function in any one of the repeaters is stopped, another repeater capable of relaying and publishing information is retrieved. When continuing to publish information via another retrieved repeater, the speed of publishing information is faster than

200580023946.9 The release speed before the stop of the relay function. As a result, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0064] Therefore, even another repeater connected under the repeater whose relay function has stopped can use the posted information to continue processing such as replay without being affected by the function stop.

[0065] According to the invention described in claim 10, in addition to the effects of the invention described in claim 9, the distribution is continued while gradually increasing the distribution speed of the distribution information via another connected repeater to The maximum value of the publishing speed as the upper limit, so that the repeaters belonging to the lower level can get the necessary publishing information more quickly.

[0066] According to the present invention described in claim 11, in addition to the effects of the present invention described in claim 9 or 10, since the posting is continued by making the posting speed faster than the posting speed before the relay function is stopped, until The amount of storage in the repeater that is the distribution destination of the distributed information becomes a predetermined amount, so it is possible to reliably continue the distribution of information in the repeater belonging to the level below the repeater whose relay function has been stopped. Processing. According to the invention described in claim 4, a main path and a sub path are formed to connect a plurality of repeaters to one repeater, and the release information issued via the main path is used for external output processing in the one repeater, And it is used to publish to another repeater belonging to the hierarchy below the one repeater. The release information distributed via the main path or the sub-path as one of the paths is also used to distribute to another repeater belonging to a lower level. By connecting multiple lines to each node, redundancy can be increased when preparing to stop the relay function of any one node, and it is possible to prevent the external output processing in the repeater belonging to a lower level from being stopped.

[0067] According to the invention described in claim 12, a main path and a sub path are formed to connect a plurality of repeaters to one repeater, and the release information issued via the main path is used for the outside of the one repeater The output is processed and used for publishing to another repeater belonging to the hierarchy below the one repeater. The release information distributed via the main path or the sub-path as one of the paths is also used to distribute to another repeater belonging to a lower level. By adding multiple

200580023946.9 The first line is connected to each node. When preparing to stop the relay function of any node, redundancy can be added, and the external output processing in the repeater belonging to the lower level can be prevented from being stopped.

[0068] According to the present invention described in claim 13, in addition to the effects of the present invention described in claim 12, a relay belonging to a repeater at a level above the one repeater on the main path When the function is stopped, the information posted via the sub-path is switched to provide external output processing. Therefore, the external output processing in the one repeater will not be interrupted.

[006] According to the present invention of claim 14, in addition to the effects of the present invention of claim 13, when the posting information posted via the sub-path is switched to be provided to the external output processing, it is retrieved that belongs to that one The publisher or new repeater of the hierarchy above the repeater, and the retrieved publisher or new repeater is connected to the one repeater, thereby forming a new path. Therefore, redundancy can be ensured and maintained.

[0070] According to the invention described in claim 15, in addition to the effects of the invention described in claim 12, a relay belonging to a repeater at a level above the one repeater on the subpath When the function stops, a publisher or a new repeater belonging to a hierarchy above the one repeater is retrieved, and the retrieved publisher or new repeater is connected to the one repeater, thereby forming a new sub path. Therefore, even if the relay function in the repeater located on the sub-path stops, a new sub-path can be formed, and redundancy can be ensured and maintained.

[0071] According to the invention described in claim 16, in addition to the effects of the invention described in claim 14 or 15, a publisher or a repeater is retrieved so that the one at the level of which the relay belongs Another repeater is included on the new main path so that the posted information can be received via the repeater on the same level.

[0072] According to the invention described in claim 17, in addition to the effects of the invention described in any one of claims 9 to 16, repeaters located on different levels are connected to the one repeater , Thereby forming multiple paths to the one repeater. Therefore, even when

200580023946.9 When the possibility of failures such as the stop of the relay function is different in different levels, sufficient redundancy can be reliably ensured.

[0073] According to the invention described in claim 18, when the relay function in any one of the repeaters is stopped, another repeater capable of relaying and publishing information is retrieved. When the release of the released information is continued via another retrieved repeater, the release speed of the released information is made faster than the release speed before the relay function is stopped. Therefore, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0074] Therefore, even another repeater connected under the repeater whose relay function has stopped can use the posted information to continue processing such as playback without being affected by the function stop.

[0075] According to the invention described in claim 19, a main path and a sub path are formed to connect a plurality of repeaters to one repeater, and the release information issued via the main path is used for the outside of the one repeater Output processing, and used for publishing to another repeater belonging to the level below the one repeater, and publishing information published via the main path or sub-path as one of the paths is also used for publishing to the lower level Another repeater in the hierarchy. By using multiple lines for repeaters, redundancy can be increased when preparing to stop the repeater function of any one repeater, and it is possible to prevent external output processing in repeaters belonging to a lower level from being stopped.

[0076] According to the invention described in claim 20, when the relay function in any one of the repeaters is stopped, another repeater capable of relaying and publishing information is retrieved. When the distribution of the posted information is continued via another retrieved repeater, the computer continues the posting by making the posting speed of the posted information faster than the posting speed before the relay function is stopped. Therefore, it is possible to continue the processing of posting information in the relays belonging to the hierarchy below the relay whose relay function has been stopped.

[0077] Therefore, it is even connected to another one under the repeater whose repeater function is stopped

200580023946.9 The repeater can also use the release information to continue processing such as replay, without being affected by the stop of the function.

[0078] According to the invention described in claim 21, the computer functions as follows: a main path and sub-paths are formed to connect a plurality of repeaters to one repeater, and the published information issued via the main path is used in the one The external output processing in the repeater and is used for publishing to another repeater belonging to the level below the one repeater, and the publishing information issued via the main path or sub-path as one of the paths is also used for Publish to another repeater belonging to a lower level. By using multiple lines for multiple repeaters, redundancy can be increased when preparing to stop the repeater function of any one repeater, and it is possible to prevent external output processing in repeaters belonging to a lower level from being Stop.

Description of the drawings

[0079] FIGS. 1A and 1B are block diagrams showing a schematic structure of a network system according to the first embodiment. Figure 1A is a block diagram showing the physical connection mode of the network system. Fig. 1B is a block diagram showing a connection mode of a network system as a topology.

FIG. 2A shows the structure of nodes included in the network system according to the first embodiment, and FIG. 2B shows details of information stored in the storage unit 3.

Fig. 3 is a flowchart showing the entire processing in the node according to the first embodiment.

4A to 4E are flowcharts (I), showing the details of processing in the node according to the first embodiment, and respectively show upper node connection processing, data receiving processing, lower node connection processing, exit message response processing, and Node exit processing.

5A and 5B are flowcharts (II), showing details of processing in the node in the first embodiment, and respectively showing data transmission processing and data playback processing.

Fig. 6 is a flowchart showing data display processing in a node according to the first embodiment.

7A, 7B, and 7C are diagrams (I) showing the state of packet release in the network system according to the first embodiment and diagrams (i), (ii), and (iii) respectively showing details of the state = diagrams 8A, 8B, and 8C are a diagram (II) showing the packet distribution state in the network system according to the first embodiment and diagrams (iv), (ν), and (vi) respectively showing details of the state.

200580023946.9 FIGS. 9A, 9B, and 9C are diagrams (III) showing the state of packet release in the network system according to the first embodiment and diagrams (vii), (viii), and (ix) respectively showing details of the state. .

10A and 10B are diagrams (i) and (ii), respectively, showing details of the package release state in the case where node exit occurs in the network system according to the first embodiment.

11A, 11B, and 11C are diagrams (i), (ii), and (iii), respectively, showing details of the packet publishing state in the case of reconnection after the node exit is completed in the network system according to the first embodiment .

12A, 12B, and 12C are diagrams (i), (ii), and (iii), respectively, showing the case of restoring the playback delay after node exit and reconnection in the network system according to the first embodiment Details of the package release status.

13A, 13B, and 13C show the transmission/reception of data in the node in the case of restoring the playback delay after node withdrawal and reconnection in the network system according to the first embodiment, and respectively show the node withdrawal The previous state, the state after the node exits, and the state after the replay delay is restored.

14A and 14B are flowcharts showing data display processing in nodes in the first modification and the second modification of the first embodiment, respectively.

Fig. 15 is a block diagram showing a schematic structure of a network system according to the second embodiment.

FIG. 16 is a block diagram showing the general structure of nodes included in the network system according to the second embodiment.

17A and 17B show the detailed structure of the node according to the second embodiment and show the details of the topology table and the operation of the buffer memory, respectively.

FIG. 18 is a flowchart showing the conventional publishing operation in the network system according to the second embodiment.

19 is a block diagram showing the schematic structure of the network system according to the second embodiment after the relay function of some nodes is stopped.

20A, 20B, and 20C are flowcharts showing the operation of the lower node when the relay function of some nodes is stopped, and the operation of the buffer memory is shown.

FIG. 21 shows the operation of the lower node when the relay function of some nodes is stopped.

22A and 22B show operations in a modified network system according to the second embodiment. FIG. 22A is a flowchart showing the operation, and FIG. 22B shows the operation corresponding to the

200580023946.9 The operation of the buffer memory.

Fig. 23 is a block diagram showing a schematic structure of a network system according to the third embodiment.

FIG. 24 is a block diagram showing the schematic structure of the network system according to the third embodiment after the relay function of some nodes is stopped.

FIG. 25 is a flowchart showing the normal publishing operation of the network system according to the third embodiment.

Fig. 26 is a flowchart showing the operation of lower-layer nodes when the relay function of some nodes is stopped.

Label description

[0080]

1, 100 CPU

<td>2</td><td>Connect authentication unit</td>

<td>3</td><td>Storage unit</td>

<td>4</td><td>Input unit</td>

<td>5</td><td>Output unit</td>

<td>6</td><td>Message sending/receiving unit</td>

<td>7</td><td>Data sending/receiving unit</td>

<td>8, 109</td><td>bus</td>

<td>10</td><td>The first upper node information storage area</td>

<td>11</td><td>The second upper node information storage area</td>

<td>12</td><td>Send data number information storage area</td>

<td>14</td><td>Received data number information storage area</td>

<td>15</td><td>Replay speed information storage area</td>

<td>16</td><td>Specific value storage area</td>

<td>17</td><td>Ring buffer area</td>

<td>102</td><td>decoder</td>

<td>103</td><td>Table memory</td>

<td>104</td><td>Buffer memory</td>

<td>105</td><td> Broadband interface</td>

200580023946.9 p.

<td>106</td><td>Timer</td>

<td>107</td><td>speaker</td>

<td>108</td><td>CRT</td>

<td>NS</td><td>network system</td>

<td>S</td><td>server</td>

Ν, Ν N2, N3, N4, N5, Ν7&gt; Ns» N9, N10, Νι, N12, N13,

N14, 0-1, 1-1, 1-2, 1-3, 2-1, 2-2, 3-1, 3-2, 3-3, 3-4, 4-1, 4-2, 4-3 nodes

NT network

L, L, line

LM, LM⁵Main line

LS, LS⁵ Sub-line

Specific implementation of NT, NT2 network system

[0081] (1) First Embodiment The first embodiment of the present invention will be described below with reference to FIGS. 1A and 1B to 13A-13C. The first embodiment to be described below relates to a case where the present invention is applied to a network control process in which the network control process is used to control the distribution mode of content in a network system in which content is distributed and all The network system includes: a server as a node, the node is a publishing device as a publishing source of the content of the published information; and a plurality of nodes as a user terminal, the user terminal is connected to include a plurality of levels below the server Tree structure.

[0082] FIGS. 1A and 1B show a schematic structure of a network system according to the first embodiment. 2A and 2B are block diagrams showing the detailed structure of nodes included in the network system. Figures 3 to 6 are flowcharts, each showing a publishing process performed in a node according to the present invention. Figs. 7A to 7C to Figs. 13A to 13C specifically show the issuance processing.

[0083]

200580023946.9 First, when the network system of the first embodiment is viewed as a physical connection mode, as shown in FIG. 1A, the network system NS is constructed so that the server S and the multiple nodes N as user terminals can pass through as a wired circuit or wireless The lines L of the circuit are connected to each other so as to be able to send/receive information to/from each other via a network NT such as an Internet line. Taking the network system NS shown in FIG. 1A as a topology with the server S at its vertex, as shown in FIG. 1B, two nodes N are connected to the server S via a line L, and two nodes N are connected to Each of node N. Through the topology in which the nodes N are connected in a tree shape using the server S as the apex, the required content is published from the server S to the node N that needs the content.

[0084] The specific structure of the node N included in the network system S is described below with reference to FIGS. 2A and 2B.

[0085] As shown in FIG. 2A, the node N according to the first embodiment includes: a CPU1 as a detection device, a consumption control device, a reset device, and a release control device; the authentication unit 2 is connected; it is constructed by a hard disk, a semiconductor memory, etc. The storage unit 3; the input unit 4 composed of a mouse, a keyboard, etc.; an output unit 5 composed of a monitor for displaying images, a speaker for outputting sound and a decoder for decoding the sound, etc.; message sending/ The receiving unit 6 and the data transmitting/receiving unit 7. The CPU 1, the connection authentication unit 2, the storage unit 3, the input unit 4, the output unit 5, the message sending/receiving unit 6, and the data sending/receiving unit 7 are connected to each other via a bus 8 to be able to send/receive information to each other.

[0086] The outline operation is described below.

First, the message sending/receiving unit 6 is functionally divided into: a part connected to a node N (or server S) located on a higher level via a line L and sending/receiving messages from a node located on a higher level; and via The line L is connected to the node N located on the lower level and the part that transmits/receives messages from the node located on the lower level. The message here indicates various control information necessary to distribute the required content in the network system NS. By receiving/sending messages, an environment for publishing actual content is formed.

[0087] On the other hand, like the message transmission/reception unit 6, the data transmission/reception unit 7 is

200580023946.9 is functionally divided into parts that are connected to a node N located on a higher level via a line L and send/receive data from a node located on the higher level; and connected via a line L to a node located on a lower level. Node N also sends/receives parts of data from nodes located on a lower level. The data indicates data in the form of packets including sounds or images constituting the content itself distributed in the network system NS. In an environment formed by message transmission/reception, the slave server S publishes data as content to each node.

[0088] For data in the form of packets, it is assumed that consecutive packet numbers from the head of the content are assigned to data packets constituting a content block (for example, the content of a movie or the content of a piece of music). The data sent as packets is divided into small packets whose unit is smaller than the packet. In addition, for small packets, consecutive small packet numbers from the head of the content are assigned.

[008] For example, in a case in which the network system NS is a network system for distributing chargeable content, the connection authentication unit 2 passes in a case in which the node N enters the network system NS or in which another node is newly connected In the case of N, authentication information is sent/received from the server S to perform a so-called authentication process for determining whether the node N is a node to which content is allowed to be distributed under the control of the CPU 1 .

[0090] In addition, the storage unit 3 temporarily or in a nonvolatile manner rewritably stores information to be described later, and if necessary, outputs the information to the CPU Κ

[0091] On the other hand, when an operation such as specifying content to be replayed is performed by using the node N, the input unit 4 generates an operation signal corresponding to the operation performed, and outputs the operation signal to the CPU 110 CPU 1. The operation signal is received and the other components of the node N are controlled, thereby performing processing of publishing and replaying desired content.

[0092] The playback process is performed by using the output unit 5 under the control of the CPU 1.

[0093] The specific structure of the storage unit 3 will be described in detail with reference to FIG. 2B. Figure 2B shows the storage unit 3 partitioned according to the type of information stored₀

200580023946.9 p.

[0094] As shown in FIG. 2B, the storage unit 3 is composed of the following: a first upper-level node information storage area 10 for storing information that is located on the top of the node N including the storage unit 3 in the topology shown in FIG. 1B The upper node information of the node N of the upper layer; the second upper node information storage area 11 is used to store the upper node information of the upper node N that is topologically located in the upper layer of the upper node N; the lower node information storage area 12 is used The storage means the lower-level node information of one or more nodes N that are connected topologically to the node N that includes the storage unit 3, and the information number is equal to the lower-level node number; the sending data number information storage area 13 is used to store the representation The transmission data number information including the packet number of the data sent to the lower node; the received data number information storage area 14 is used to store the reception of the packet number representing the data received by the node N itself including the storage unit 3 Data number information; playback speed information storage area 15, used to store playback speed information representing the playback speed in the output unit 5 of images and sounds corresponding to the received data; specific value storage area 16, used It is stored as a specific value such as the minimum amount of stored data preset in the ring buffer area which will be described later; and the ring buffer area 17 is used to temporarily store data that is actually distributed as content.

[0095] The node information stored in the first upper node information storage area 10, the second upper node information storage area 11, and the lower node information storage area 12 specifically includes an IP (Internet Protocol) global address representing the node N.

[0096] The ring buffer area 17 is a ring buffer type storage area for temporarily storing data corresponding to distributed content in a FIFO manner. The ring buffer area 17 sequentially stores packets (and small packets) as content data and outputs the packets according to the storage order as a rule to provide them to the playback processing in the output unit 5.

[0097] Next, referring to the flowcharts shown in FIGS. 3 to 6, the processing of allowing the new node N to newly enter the network system NS, receiving the distribution data corresponding to the content, and replaying the content according to the first embodiment will be described, and During replay, the function of relaying data to other nodes N connected to the new node N is stopped due to the withdrawal of the new node from the network system NS.

200580023946.9 The processing performed in the case is as processing in each node N.

[0098] In the case that the new node N is allowed to be located at the position of the next layer of any node N in the existing network system NS, enter the node N (the following will newly enter the network system NS and execute according to the flowchart of FIG. 3 The node N for data reception processing and replay processing is called "entry node N" to distinguish it from other nodes that have been connected to the network system NS) to perform the connection of the incoming node N to the upper node N (or the network system NS) The server S located on the uppermost layer in the process (steps S1 and S2) ο When the connection request is rejected by the upper node N (No in step S2), the entry node N cannot join the existing network system NS at this time, thus completing Enter the processing in node N.

[0099] On the other hand, after the upper node N (or server S) is allowed to enter in the determination of step S1 and the necessary connection processing is performed through the upper node N (or server S) (Yes in step S2), it is determined that the entry node In N, whether the input unit 4 performs an operation of exiting from the network system NS in which the node N exists (step S3) ο

[0100] When the entry node N exits from the network system NS (Yes in step S3), the exit operation is performed in the entry node N (step S4), and the processing in the entry node N is completed.

[0101] On the other hand, when the process of exiting from the network system NS is not performed but the data receiving process or the like is continuously performed (No in step S3), the entering node N executes the process of receiving necessary data from the upper node N (step S5), and replay the received data and output the replayed data by using the output unit 5 (step S9) ο When another connected node N needs it, the incoming node N performs a disconnection from the incoming node N The exit message response process of the connection between the other node N and the entry node N (step S8), returns to step S3 and continuously executes the data reception and replay processing.

[0102] In parallel with the data replay process (step S9), the entry node N executes the process of connecting another node N to the next layer of the entry node N (step S6) and sends (relays) data to the connected node Processing of lower node N (step S7).

200580023946.9 p.

[0103] The processing in step S1 and steps S4 to S9 in FIG. 3 will be described in detail below in order.

[0104] First, the processing of step S1 will be described in detail by using the flowchart of FIG. 4A.

[0105] As shown in FIG. 4A, in the processing of step S1, first the entry node N sends a request message to the upper node N via the line L (step S10), and waits for a response to the request from the upper node N (step S11) , And confirm the reply (step S12), wherein the request message is used to make the entry node N enter as the next node N of another node N that is the previous node.

[0106] When the entry node N is allowed to enter the network system NS in response to the reply (Yes in step S12), the entry node N stores the upper node information including the IP address corresponding to the upper node N in the entry node In the first upper node information storage area 10 in the storage unit 3 of N, the upper node information of the upper node including the IP address corresponding to another node above the upper node N is stored in the storage unit of the entry node N 3 in the second upper node information storage area 11 (step S13), and proceed to step S2 as shown in FIG. 3₀

[0107] On the other hand, when the entry node N is not allowed to enter the network system NS in the determination of step S12 (No in step S12), the entry node N cannot display its function. Also in this case, after switching to step S2 shown in FIG. 2 (No in step S2), the process of entering the node N is completed.

[0108] Next, the data receiving process in step S5 shown in FIG. 3 will be described in detail by using the flowchart shown in FIG. 4B.

[0109] As shown in FIG. 4B, in the processing of step S5, first the entering node N sends a message for requesting desired data to the connected upper node via the line L (step S15), and confirms whether There is a sending permission answer from the upper node N for this message

200580023946.9 second (step S16) ο

[0110] When there is a transmission permission reply (Yes in step S16), the entering node N receives a packet including the data desired by the entering node N according to the reply (step S17), and proceeds to step S6 as shown in FIG. 3 Or S9-On the other hand, when the transmission permission response is not obtained from the upper node N in the determination of step S16 (No in step S16), there is a possibility that a failure occurs on the line between the upper node N and the incoming node N Sex. As a result, the entering node N performs the above-mentioned processing in step S1 (refer to FIG. 4A) to eliminate the failure and be able to receive data, returns to the processing of step S15 again, and receives data from the upper node N connected again (step S15 or S17) ) Ο

[0111] Next, the lower node connection processing in step S6 shown in FIG. 3 will be described by using the flowchart shown in FIG. 4C.

[0112] As shown in FIG. 4C, in the processing of step S6, it is first determined whether the connection request message from the node N connected to the next layer of the entry node N has been sent to the entry node N (step S20). When the connection request message is not sent (No in step S20), the entry node N switches to step S7 in FIG. 3. When the connection request message has been sent (Yes in step S20), the connection authentication unit 2 included in each of the lower node N and the entry node N is used to send the connection request message to the lower node N. Perform authentication processing between the entry node N and the entry node N (or between the lower node N and the server S via the entry node N) to determine whether the lower node N is a node N with the qualification to enter the network system NS (steps S21 and S22) ο

[0113] In the case where the lower node N cannot be allowed to enter the network system NS through the authentication process (No in step S22), the fact is sent to the lower node N as a connection prohibition message (step S25), and the procedure proceeds to Step S7 shown in FIG. 3.

[0114] On the other hand, when the lower node N is allowed to enter the network system NS in the authentication process in the determination of step S22 (YES in step S22), this fact is regarded as the connection permission cancellation

200580023946.9 The second message is sent to the lower node N (step S23), and the lower node information including the IP address corresponding to the next node N, etc. is stored in the lower node information storage area 12 in the storage unit 3 of the entry node N (Step S24), and the procedure proceeds to step S7 as shown in FIG. 3.

[0115] Next, the data transmission processing in step S7 shown in FIG. 3 will be described by using the flowchart shown in FIG. 5A.

[0116] As shown in FIG. 5A, in the processing of step S7, it is first determined whether a request for transmitting data to be reproduced in the lower node N has been received as a request from the next layer connected to the entry node N. The message of node N is sent (step S35). When no message is received through the entry node N (No in step S35), the procedure proceeds to step S8 shown in FIG. 3₀

[0117] On the other hand, when it is determined in step S35 that the message has been sent (Yes in step S35), next, in response to the message, it is determined whether the packet to be sent from the ingress node N is as described in detail below. An empty package (a package that includes only header information and does not include entity image information that constitutes content, etc.) (step S36). When the packet is not an empty packet (No in step S36), the packet that is not an empty packet is transmitted as content data to the lower node N via the line L (step S38), and the procedure proceeds to step S8 shown in FIG. 3.

[0118] On the other hand, when it is determined in step S36 that the packet to be sent is an empty packet (Yes in step S36), the data received by the ingress node N before the processing in step S7 shown in FIG. 5A starts The packet number of is compared with the packet number of the physical data to be sent to the lower node N (that is, the physical data such as image data and sound data that are not included in the empty packet). In the case where the numbers are not continuous (that is, an empty packet is received), by concatenating the small packet number immediately before the empty packet and the small packet number immediately after the empty packet, the small packet number immediately following is placed in the immediate vicinity. Following the previous packet number (step S37), the data constituting the content in the packet with the arranged packet number is sent to the lower node N (step S38), and the procedure proceeds to step S8 shown in FIG. 3₀

200580023946.9 p.

[011] Next, the exit message response processing in step S8 shown in FIG. 3 will be described in detail by using the flowchart shown in FIG. 4D.

[0120] As shown in FIG. 4D, in the processing of step S8, it is first determined whether any one of the other nodes N connected to the entry node N (specifically, the one connected to the upper layer of the entry node N The upper node N or the lower node N connected to the next layer of the entry node N) receives the message that the node N will withdraw from the network system NS (step S26). In the case that the message has not been received (No in step S26), the procedure returns to step S3 in FIG. 3. On the other hand, in the case of receiving a message requesting exit (Yes in step S26), it is determined Which of the upper-level node N and the next-level node N sent the message (step S27)₀

[0121] When the exit request message has been sent from the upper node N (the "upper node" in step S27), according to the representation stored in the second upper node information storage area 11 in the storage unit 3 of the entry node N The node information of the upper-level node of the upper-level node N is connected to the upper-level node N (that is, the node N that sent the exit request message) to perform the upper-level node connection processing in step S1 above , Thereby restoring the topology (step S1), and the procedure returns to step S3 in FIG. 3.

[0122] On the other hand, when the exit request message has been sent from the next node N (the "lower node" in step S27), the entry in the storage unit 3 of the entry node N is deleted from the lower node information storage area 12. The node information of the lower node N is stored in the lower node information storage area 12 (step S28), and the procedure returns to step S3 in FIG. 3.

[0123] Next, referring to the flowchart of FIG. 4E, the node exit processing in step S4 shown in FIG. 3 (the processing of entering the node N itself to exit from the network system NS) will be described in detail.

[0124] As shown in FIG. 4E, in the processing of step S4, the above exit request message (refer to FIG. 4D) is first sent to the upper node N connected to the upper layer of the entry node N (step

200580023946.9 p.

S30) ο Next, similarly send the above exit request message to the lower node N connected to the next layer of the entry node N (step S31) ο After sending the message, the entry node N executes the exit from the network system NS deal with.

[0125] Finally, the data playback processing in step S9 shown in FIG. 3 will be described in detail by using the flowchart shown in FIG. 5B.

[0126] As shown in FIG. 5B, in the processing of step S9, the replay flag (that is, the replay flag indicating whether the replay processing using the output unit 5 is being executed) is first checked into the node N (step S40) ₀When the playback flag is "off" (that is, playback processing is not currently performed in the output unit 5) (OFF in step S40), it is next determined whether the amount equal to or not has been stored in the ring buffer area 17 Or data greater than the specific value "t" which is the specific value of the preset storage amount (step S45) ο

[0127] When no data with a data amount equal to or greater than the specific value "t" is stored in the ring buffer area 17 (No in step S45), if the data playback processing is performed in this state (in other words, it consumes If the data in the ring buffer area 17 is lost), the ring buffer area 17 enters a so-called underrun state, and there is a possibility that the playback of images and music will be interrupted. As a result, in order to further store data, the program returns to step S3 via step S8 shown in FIG. 3.

[0128] On the other hand, when it is determined in step S45 that the amount of data equal to or greater than the specific value "t" has been stored (YES in step S45), the playback flag that has been "off" is set to "On" (step S46), the process of replaying the stored data (for example, in the case of image information, the process of displaying image information) is executed in a manner similar to the related art (step S47), and the program progresses to FIG. Step S8 shown in 3₀

[012 On the other hand, when the playback flag is "on" in the determination of step S40 (that is, when playback processing is currently being performed in the output unit 5) (No in step S40), Similar to the above determination in step S45, it is determined that the current ring buffer area 17 is

200580023946.9 Whether the data with an amount equal to or greater than the specific value "t" is stored (step S41) ο When the data with an amount equal to or greater than the specific value "t" has been stored (Yes in step S41), it is similar In step S47, as in the prior art, the playback mode such as the display speed of image data is set to the normal mode (step S42). The playback process is executed in accordance with this setting (step S44). After that, the procedure proceeds to step S8 shown in FIG. 3.

[0130] Conversely, when it is determined in step S41 that the amount of data equal to or greater than the specific value "t" has not been stored (No in step S41), the data playback mode is changed according to the storage amount (step S43), The playback process is executed in accordance with this setting (step S44), and the procedure proceeds to the process of step S8 shown in FIG. 3.

[0131] When the setting of the playback mode is changed in step S43, when data of an amount equal to or greater than the specific value "t" has not been stored, the playback mode is set to reduce the playback process in step S44. The amount of data consumed in the ring buffer area 17 reduces the rate of decrease in the storage amount of the ring buffer area 17 (that is, the consumption amount per unit time of the data stored in the ring buffer area 17). Specifically, for example, the amount of data read from the ring buffer area 17 per unit time is set to reduce it to approximately 4/5 of the maximum value of the normal amount. More specifically, there is a method of controlling the reading amount so that the same packet is read twice in a cycle such as once every 5 packets. In this case, when the relay function in the upper node N is not stopped, it is sufficient to set the period to zero, and the period is shortened as the storage amount in the ring buffer area 17 decreases.

[0132] The degree of decrease in the amount of data read from the ring buffer area 17 per unit time may be such a degree that the user cannot visually perceive the decrease. The value of 4/5 can be changed to this extent.

[0133] Next, the data display processing in step S44 shown in FIG. 5B will be described in detail by using the flowchart of FIG. 6. The data display processing is based on a preset condition of changing the setting of the speed of reading data from the ring buffer area 17 in the processing of step S43.

[0134] As shown in FIG. 6, in the processing of step S44, first according to the processing of step S43

200580023946.9 reads the data as the image information from the ring buffer area 17 by the reading amount per unit time (reading speed) set in Section S50 (step S50). The read data is decoded in the output unit 5 (step S51) and the decoded data is displayed on an unshown display or the like (step S52). Also in the case of sound information, it is similar to the image information In the case of the method, the data is read from the ring buffer area 17 at the set reading speed (step S50). Decode the read data and generate decoded data from a speaker, etc. not shown (steps S51 and S52) =

[0135] Next, a series of network control processing will be described in more detail with reference to FIGS. 7A to 7C to FIGS. 13A to 13C including the flow of a packet composed of data as content.

[0136] In FIGS. 7A to 7C to 12A to 12C, it is assumed that in a topology whose vertex is server S, two nodes N1 and N2 are connected to the first level of the next layer of server S. Two nodes N3 and N4 are connected to the next layer of node M. Two nodes N5 and N6 are connected to the next layer of node N2. Two nodes N7 and Ng, two nodes Ng and M. , Two nodes Nil and N12 and two nodes N13 and N14 are respectively connected to node N₃&gt; Ns Ns and the next layer of N6. The following describes the distribution of image data stored in advance as content in the server S in the form of packets to the lower nodes Νι to N14 and the nodes Νι to Nm in the network system NS having the connection mode shown in the topology having this structure. The processing performed when the node N4 withdraws from the network system NS.

[0137] In addition, it is assumed that each of the server S and the nodes N1 to N6 has a ring buffer area 17 and also performs relaying of the packet P to other lower-level nodes (each has the ring buffer area 17) while storing the packet P For data processing (refer to steps S7 and S9 in Figure 3). In FIGS. 7A to 7C to FIGS. 13A to 13C, a packet P is represented as a frame (port), and the number in each frame represents the packet number.

[0138] In addition, in FIGS. 7A to 7C to FIGS. 12A to 12C, the ring buffer area 17 in each of the nodes to Ng is represented as a line. However, in the packet input/output processing, the right and left ends of each ring buffer area 17 are connected in a ring. Provide a package

200580023946.9 gives replay processing. Every time a packet is released to the node N of the next layer, the oldest packet among the packets stored in the ring buffer area 17 is replaced with a new packet issued from the node N of the upper layer. In this way, the above-mentioned FIFO buffer memory is realized.

[013] The downward hollow arrow used to show the circular buffer area 17 in the server S in FIGS. 7A to 7C to FIGS. 13A to 13C indicates that the packet represented by the box pointed to by the arrow at its left end is sent from the server S Time sequence. The upward solid arrow displayed for the ring buffer area 17 in each node N in FIGS. 8A to 8C to FIGS. 13A to 13C indicates that the image data stored in the position pointed by the arrow in each packet is displayed at this time. In addition, what is displayed in the display (frame) of the packet in the ring buffer area 17 of any one of the server S and the node N indicates that no data is stored in the ring buffer area 17 corresponding to the packet.

[0140] Now suppose that in each of the examples shown in FIGS. 7A and 7B to FIGS. 13A and 13B, the specific value "t" in each node N (specifically, the insufficient storage amount in the ring buffer area 17 The lower limit "t") corresponds to three packages.

[0141] First, before the package is released, the packages to be released are stored in the ring buffer area 17 as shown in FIG. 7A in the order of release. These packets are to be distributed to the nodes N] to N4 connected to the lower layer according to the numbers. Specifically, as shown in FIG. 7A, at the time when the packet Po is output from the server S, the packet Po (with the packet number "0") is sent to the line L± connecting the server S and the nodes Ni and Ν?_oAfter that, the transmitted Po is stored in the ring buffer area 17 in each node N, and is relayed by the node N located on the lower level after the time as shown in FIGS. 7B and 7C has passed.

[0142] When the package Po is published to the nodes N? to N14 connected to the bottom of the network system NS, then as shown in FIG. 8A, the transmission of the package P to be published after the package Po is started.

[0143] For example, when the image data of three packets are stored in the nodes N? to N14 connected on the bottom of the network system NS as shown in FIG.

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The image data in Po starts the image playback processing in nodes N1 to N14.

[0144] After completing the playback processing of one packet using the packet Po in each of the nodes M to N14 as shown in FIG. 8C, the playback processing using the next packet Pi is started in the nodes M to N14 and issued The fourth packet P4 from server S.

[0145] By repeating the above processing, packets as image data are sequentially issued and replayed while being stored in the ring buffer area 17 (or erased from the ring buffer area 17) in a FIFO manner. Assume that in each of the nodes M. to N14 in the first embodiment, as shown in FIG. 9A, the packets stored immediately before the packet that is currently replayed are sequentially updated.

[0146] As shown in FIGS. 9B and 9C, after publishing all the packages to be published in the server S, the ring buffer area 17 in the nodes N1 to Nm becomes empty in turn, and all the packages in the network system NS are completed. Post processing.

[0147] Next, the node N in the network system NS will be described with reference to FIGS. 10A and 10B to FIGS. 13A to 13C.₄The processing performed in a case where its relay function is stopped due to, for example, a power failure and withdrawing from the network system NS itself.

[0148] As shown in FIG. 10A, it is assumed that when the process of replaying, for example, the image data included in the package Pi is completed and the package P is simultaneously transmitted from the server S₅When arriving at each of the nodes N1 to Nm, the node N4 withdraws from the network system NS due to the above reasons (refer to FIG. 4D). After exiting, the distribution of the package P5 to the lower nodes Ng and Νι is naturally disconnected. . In this case, as shown in FIG. 10B, the current node Νι is executed. The process of reconnecting to the node M as the upper node N and reconnecting the node Ng to the reconnected Νι. (Refer to step S1 in FIG. 4D), and republish the package P5 that has not been published before the publishing sequence. As a result, at nodes Ng to Nι. In the ring buffer area 17 included in each of, compared with other nodes N1 to Ng and nodes Nii to Nm, the rewrite timing is only delayed by one packet. As a result, there are only two packets (packets P3 and P4) that have not been subjected to playback processing as shown in FIG. 10B, and so-called data delay has occurred (No in step S41 in FIG. 5B). after that,

200580023946.9 Until the release of all packages is completed, continue to node N in nodes Ng and Νιο₉To the replay in Νιο from other nodes N1 to N₈And nodes Nil to N14 only delay the state of one packet.

[014] Therefore, in the first embodiment, as shown by the hatched arrows in FIGS. 11A and 11B, in the nodes Ng and No, it is possible to read data from the ring buffer area 17 after the time when the data delay occurs. The speed is slower than at other nodes N1 to N₈And the speed in the nodes Nil to N14 (No in step S41 in FIG. 5B and step S50 in FIG. 6). Finally, as shown in FIG. 11C, the number of packets to be reproduced is restored to 3 as a specific value (packets P4 to P6 in the case of FIG. 11C).

[0150] From the state of the ring buffer area 17 in the node N9 in FIG. 11C or 12A and the node N₈The comparison between the states of the middle ring buffer area 17 clearly shows that the number of the packet that has not been reproduced in each ring buffer area 17 is restored to 3. At node N₈The packet to be replayed in is packet P5, but at node N₉The package to be replayed in is package P_4OSince the upper node Z withdraws from the network system NS, when comparing the replay timing on the time base of a series of packets P, a so-called replay delay occurs in the nodes Ng and Nιο under the node N4 (that is, at the node The playback timing of the same content in N has deviated). Therefore, for example, in the case where the user of the node Ng and the user of the node Ng play a so-called network game, the occurrence of a playback delay in these two nodes will disturb the normal use state of the node N.

[0151] As a result, in the network control processing of the first embodiment, an empty packet is issued from the server S to the network system NS except for the node N whose playback delay has occurred due to the withdrawal of the upper node N from the network system NS. Therefore, the content playback timings of all nodes N included in the network system NS are synchronized with each other.

[0152] In the first embodiment, as shown in FIG. 12A, among the contents stored in the ring buffer area 17 of the server S before being published, empty packets are removed at a predetermined timing or interval in anticipation of future playback delays. Poo is inserted into other bags.

[0153] As shown in FIGS. 12A and 12B, at nodes Ng and M, for example. Replay delay occurs in the

200580023946.9 In the first case, the empty package is published to all nodes except nodes Ng and N]o, that is, nodes N1 to N8 and nodes Nil to N14 (refer to Figure 5A). As a result, as shown in FIG. 12C, the timing of reproducing the published packets in all the nodes Ni to Nm included in the network system NS becomes the same, and the playback delay in the nodes N1 to Ni4 is eliminated.

[0154] With reference to FIGS. 13A to 13C, the connection between the nodes Ng and Νι will be described in detail. Changes in the transmission/reception time of packets in the node N of the upper and lower layers, and the execution of a series of network control processing. 13A to 13C show the nodes Ng and Nι connected. Packet sending/receiving status in node N of the upper layer and the lower layer. The horizontal axis uses its left end as the content release start time to indicate the release time and the vertical axis represents the packet number in the published package (specifically, the lower end of the vertical axis corresponds to the packet whose small packet number is "0" in the package Po) .

[0155] In the case where the relay function of the node N4 connected to the upper layer node in FIGS. 7A to 7C to FIGS. 12A to 12C is operating normally, the node Ng or N1. Repeat the packet from the upper level node N₄The operation of relaying to the next layer of nodes while receiving packets from node N4. Although in FIGS. 7A to 7C to FIGS. 12A to 12C, the next-level node N is not connected to the node Ng or Nιο, in order to fully explain the function of each node N included in the network system NS, it is assumed that in FIGS. 13A to 13C The other node N is connected to node Ng or Νι. The next level.

[0156] In parallel with the relay function, the node Ng or Ng stores the package P distributed from the node N4 in the ring buffer area 17 in the distribution order (refer to FIGS. 8A to 8C and FIGS. 9A to 90. Three packages P are stored) The node Ng or Νι at the time point. Perform processing such as decoding and displaying the data stored in the package P through the output unit 5 (hereinafter, the processing includes display processing when the data is image data and when the data is sound data In the example shown in Fig. 13A, when the first packet Po shown in Figs. 7A to 7C to Figs. 12A to 12C is distributed from the server S via the node M and stored in the node Ng or The time in the ring buffer area 17 in M. corresponds to the left end of the horizontal axis. From the time on the left end, subsequent packets Pi and P2 are similarly issued and stored in the ring buffer area 17. Since this time The time period until the start of the decoding and display of the data stored in the packet Po is the time To shown in Fig. 13A. The amount of storage in the ring buffer area 17 (first

200580023946.9 The amount of three packets in the first embodiment) corresponds to the amount indicated by the label "M" in FIGS. 13A and 13B.

[0157] After the processing of decoding and displaying the data in each packet P is completed, the portion of the ring buffer area 17 where the packet P has been recorded is overwritten and written by the subsequent packet P issued after the packet. In the example shown in FIG. 12A, the slave pair packet P. From the beginning of processing such as decoding and displaying the data in the data, until the data in the subsequent packet P4 is stored (overwritten) in the part where the packet Po has been stored in the ring buffer area 17, the time T is necessary.

[0158] Next, as described above with reference to FIGS. 10A and 10B, in the case where the upper node N4 of the nodes Ng and No. 1 exits from the network system NS and continues to stop the function, it is as shown in the figure from the stop to the completion. In the period of reconstruction of the topology shown in 10B and restarting the distribution of the package P, no package P is published to the nodes Ng and M. . Therefore, in the non-release period, although time has passed, no package P is released from the upper node N. In the nodes Ng and Nιο, as shown in FIG. 13B, the graph showing the publishing status of the package P from the upper node and the relay status of the package P to the lower node includes a flat part corresponding to the non-posting period. As a result, the amount of storage in the ring buffer area 17 is reduced. The gradient of the graph before and after the non-release period is the same (that is, the release speed and relay speed of package P).

[0159] Next, in the first embodiment, when there is a non-posting period, the speed of reading data from the ring buffer area 17 is reduced and underflow is prevented from occurring in the ring buffer area 17 (refer to FIG. 5B Steps S43 and S44 in). Therefore, from the point of time when the non-posting period is started, the speed of decoding and displaying data, etc., is reduced, as shown by the thick solid line in FIG. 13B. When the storage amount in the ring buffer area 17 becomes three packs or more, the speed of decoding and display, etc. is reset to the initial speed as shown in FIG. 13B. The storage amount in the ring buffer area 17 at the start of publishing is "M" in a similar manner to the case shown in 13A, and temporarily becomes smaller than "M" due to the occurrence of a non-publishing period. However, the speed of reading data from the ring buffer area 17 becomes slower, so that after the time T3 in which the data reading speed is slow has passed, the storage amount becomes the initial storage amount "M" again.

200580023946.9 p.

[0160] In FIG. 13B, in the non-posting period, the overwrite write processing in the ring buffer area 17 is stopped.

[0161] As shown in FIGS. 12A to 12C, after node N4 exits, a playback delay occurs in nodes Ng and N® that are different from other nodes N1 to Ng and nodes Nil to N14. In the first embodiment, as shown in FIGS. 12A to 12C, the package Poo is mixed in the content in advance and only published to other nodes Νι to N₈And nodes Νιι to N₁₄o

[0162] Therefore, when viewed from the positions of the nodes Ng and N®, as shown in FIG. 13C, when the empty package Poo is published to the other nodes N1 to N₈At the time when other nodes Nii to N14 (shown as "empty data" in FIG. 13C), as described in step S37 in FIG. 5A, the content is published by passing an empty packet Poo. As a result, the nodes Ng and Nι in the case of viewing the continuous content stored in the initial server S. The continuity of the packet numbers in is interrupted. As a result, the small packet number (indicated by the label "PK" in FIG. 13C) corresponding to the empty package Poo is delivered to increase the release amount at the point of release of the empty package Poo as shown in FIG. 13C, and similar It is relayed to the lower node N. Therefore, the packet number provided for processing such as decoding and display is similarly transferred and the change is made in an increased state.

[0163] As described above, in the network control processing according to the first embodiment, when the relay function in the node N located on the upper layer side in the network system NS is stopped, the content data stored in the lower node N The consumption rate is controlled to be slower than the rate before the stop. As a result, when the distribution of content data is interrupted, it is possible to prevent interruption processing or serious occurrence in the lower node N due to the consumption of content data at a speed similar to that before the stop without placing a burden on the network system NS itself. Processing delay.

[0164] Therefore, even in a case where the relay function is stopped in any one of the nodes N included in the network system NS, the stopped relay can be restarted without exerting a large influence on the processing in the lower node N Features. Therefore, the content data can be distributed reliably, while improving the reliability of the network system NS itself.

200580023946.9 p.

[0165] Since the content data is image data and the content data consumption speed is reduced by making the reduction speed of the image data storage amount in the ring buffer area 17 lower than the reduction speed before the relay function is stopped, it is possible to reduce the content data consumption speed without performing complicated speed In the case of control processing, the consumption speed is reduced with a simple structure.

[0166] In addition, by repeatedly outputting the same still image for forming moving image data multiple times, the reduction speed of the storage amount in the ring buffer area 17 is reduced so that the consumption speed can be reliably reduced by simple processing.

[0167] In addition, when the stop of the relay function is detected, the consumption speed is controlled to 4/5 of the consumption speed at the maximum value before the relay function is stopped, so that the processing in the node N can not be greatly affected. In the case of reducing the consumption speed. The reduction in the consumption speed is not limited to 4/5, and can ultimately be a reduction in the reading speed that cannot be perceived by the audience (users of node N).

[0168] Since the relay function of all nodes N except the node under the node N whose relay function has been stopped is reset before the relay function is stopped, the empty packet Pg is issued after the empty packet Pg is issued. A gradual delay occurs on the time base. As a result, it is possible to eliminate replay on the replay time base that occurs between the node N and all other nodes N due to the decrease in the time consumed per unit time in the node N under the node N where the relay function is stopped. The offset of the position.

[016 Blade

II. Revision of the first embodiment The revision of the first embodiment will now be described with reference to FIGS. 14A and 14B.

[0170] In the foregoing first embodiment, as a method of reducing the consumption speed of data stored in the ring buffer area 17, a method of reducing the speed itself of reading data from the ring buffer area 17 is used. In addition to this method, the following two methods can be used as methods to reduce the consumption speed.

200580023946.9 p.

[0171] As a first revision, not the speed of reading data from the ring buffer area 17 itself, but the decoding speed of the output unit 5 of the data read from the ring buffer area 17 can be reduced. More specifically, in the processing of step S43 in FIG. 5B, the data decoding speed in the output unit 5 is set to be reduced to about 4/5 of the speed at the maximum value in the normal state. For example, when the relay function in the upper node N is not stopped, it is sufficient to set the frame rate when decoding the still image data used to form the moving image data to 30 frames per second, and when the ring buffer area When the storage capacity in 17 decreases, setting the frame rate to 29 frames per second is sufficient. The more the amount of storage in the ring buffer area 17 decreases, the lower the frame rate is set.

[0172] In the case of changing the frame rate in the processing of step S43, as the processing in step S44 to be executed subsequently, as shown in FIG. 14A, first read from the ring buffer area 17 as image information at a normal reading speed Data (Step S53) = The read data is decoded in the output unit 5 by using the frame rate set in Step S43 (Step S54), and displayed on a display or the like not shown in the figure Decoded data (step S52) ο In the case of sound information, the data is read from the ring buffer area 17 at a reading speed similar to that in the case of image information (step S53), in the set frame Rate decodes the read data, and generates decoded data from a speaker, etc. not shown in the figure (steps S54 and S52).

[0173] As described above, according to the first revision, the data consumption speed in the ring buffer area 17 is reduced by making the data decoding speed in processing in the node N slower than the decoding speed before the relay function is stopped. Therefore, the consumption speed can be reliably reduced by simple processing.

[0174] Next, as a second embodiment, when the content data is moving image data, it is not the reading speed itself from the ring buffer area 17 and the decoding speed in the output unit 5, but the decoded data The display speed in the output unit 5 can be reduced. More specifically, in the process of step S43 in FIG. 5B, the display time of each of a plurality of pieces of still image data used to form the moving image data decoded in the output unit 5

200580023946.9 is increased to about 5/4 of the maximum display time in the normal state. Specifically, once the relay function in the upper layer function in the upper node N is not stopped, it will be compared with a still image. It is sufficient to set the display time of the corresponding still image data (that is, the display time of each still image) to 1/30 second, and when the storage capacity in the ring buffer area 17 decreases, set the display time to 1 /29 seconds is enough. As the storage amount in the ring buffer area 17 decreases, it is sufficient to make the display time longer.

[0175] In the case of changing the display time as described above in the processing of step S43, as the processing in step S44 to be executed subsequently, as shown in FIG. Data of image information (step S53) ο The read data is decoded in the output unit 5 by using the normal frame rate (step S55). After that, the decoded data is displayed on a display or the like not shown in the figure with the display time per still image set in step S43 (step S56).

[0176] As described above, according to the second revision, the ring buffer area 17 is reduced by making the display time of the still image corresponding to the still image data used to form the moving image data longer than the display time before the relay function is stopped. The rate of consumption in. Therefore, the consumption speed can be reduced more reliably by simple processing.

[0177] It is also possible to record the degree corresponding to the flowcharts of FIGS. 3 to 6 and FIG. 14 on an information recording medium such as a floppy disk or a hard disk, or obtain and record the program via the Internet or the like, and read it by a general-purpose computer. The program is fetched and executed, thereby causing the computer to function as the CPU 1 according to the first embodiment.

[0178] (III) Second Embodiment (A) Embodiment First, a second embodiment according to the present invention will be described with reference to FIGS. 15 to 22A and 22B. 15 is a block diagram showing a schematic structure of a network system according to the second embodiment. Fig. 16 is a block diagram showing the general structure of nodes included in the network system. Figure 17A

200580023946.9 Sections and 17B show the detailed structure of the node. Fig. 18 is a flowchart showing the conventional publishing operation in the network system. FIG. 19 is a block diagram showing the schematic structure of the network system after the relay function of some nodes is stopped. 20A, 20B, and 20C are flowcharts showing operations in lower nodes when the relay function is stopped. FIG. 21 shows the operation of the lower node when the relay function is stopped. 22A and 22B show operations in the revised network system according to the second embodiment.

[0180] As shown in FIG. 15, the network system NT according to the second embodiment is formed by using a tree structure with nodes 0-1 as a distribution device as vertices. Network system NT includes nodes

1-1, 1-2, and 1-3 are used as the nodes constituting the first level, nodes 2-1 and 2-2 are used as the nodes constituting the second level, nodes 3-1, 3-2, 3-3, and 3-4 is used as the node constituting the third level, and nodes 4-1, 4-2, and 4-3 are used as the node constituting the fourth level. The nodes are connected to each other via a line L, which is a wired circuit or a wireless circuit, so as to be able to transmit/receive information to each other using the node 0-1 as a vertex. As a specific example of the node, the node 0-1 at the highest level corresponds to, for example, a server as a content distribution source, and all nodes except for the node 0-1 are, for example, personal computers at home. The node can be a home set-top box or router.

[0181] In the network system NT shown in FIG. 15, the content distributed from the node 0-1 and desired by the node user is distributed via the line L through other nodes included in a hierarchy higher than the node. Obviously, the content is published in a digital state in units of so-called packages. In addition, a packet is distributed, which is assigned a consecutive packet number indicating the playback or storage order of the buffer memory 104 (refer to FIG. 16) and the like.

[0182] The specific structure of each node is described below with reference to FIG. 16 and FIGS. 17A and 17B. The detailed structure of the node 3-2 in the network system NT shown in FIG. 15 will be described below. The detailed structure of each of the other nodes is the same as that of node 3-2.

[0183] As shown in FIG. 16, the node 3-2 has a CPU 100 as a retrieval device, a connection device, a publishing relay device, a publishing control device, and a switching device; a decoder 102; a table memory 103;

200580023946.9 No. Buffer Memory 104; Broadband Interface 105; Timer 106; Speaker 107; and CRT (Cathode Ray Tube) 108 as a display device. The CPU 100, the decoder 102, the table memory 103, the buffer memory 104, the wideband interface 105, and the timer 106 are connected to each other via a bus 109.

[0184] Next, the operation will be described.

The broadband interface 105 is directly connected to the line L. As shown in FIG. 15, the broadband interface 105 in the node 3-2 is connected to the broadband interface 105 included in the node 2-1 on the upper level via the line L, and is also connected to the next level via the line L The broadband interface 105 included in the nodes 4-1 to 4-3. The transmission/reception of content and the transmission/reception of control information required for content transmission/reception can be performed in the node in units of packets.

[0185] In the table memory 103 as a nonvolatile memory, the topology table shown in FIG. 17A is stored. In the topology table T, in addition to the layer information indicating the level, it also includes the node number and the IP (Internet Protocol) address in the network system N, where the node number is used to store the topology table T according to the table memory 103 The position of the node in the network system NT is used to identify other nodes located on a higher or lower level. Since the topology table T shown in FIG. 17A corresponds to the node 3-2, it includes the layer of the node 1-1 on the layer (layer 2) two layers higher than the node 3-2 as shown in FIG. 15 Information, the node number of node 1-1 and the IP address of node 1-1 (for example, "100.100.10.10").

[0186] Similarly, the topology table T includes: the layer information of the node 2-1 located on the upper level (layer 1) of the node 3-2, the node number of the node 2-1, and the IP of the node 2-1 Address (for example, "100.100.10.21"); the layer information of node 4-1, the node number of node 4-1, and the IP of node 4-1 on the layer below node 3-2 (layer-1) Address (for example, "100.100.10.30"); the layer information of node 4-2, the node number of node 4-2, and the IP of node 4-2 located on the layer below node 3-2 (layer-1) Address (for example, "100.100.10.31"); and the layer information of node 4-3, the node number of node 4-3, and the node number of node 4-3 located on the layer below node 3-2 (layer-1) IP address (for example "100.100.10.32");

200580023946.9 p.

[0187] Referring to FIG. 16, the buffer memory 104 as a volatile memory is a ring buffer memory in a so-called FIFO (First In First Out) form. The buffer memory 104 only stores the data corresponding to the published content according to the publishing order with a preset recording capacity, reads the data according to the stored order under the control of the CPU 100, and transfers the read data via the bus 109 Output to decoder 102ο

[0188] The operation of the buffer memory 104 when the network system NT is in a normal state will be described below with reference to FIG. 17B.

[0189] As described above, the buffer memory 104 is configured in a ring shape. For example, as conceptually shown in the upper part of FIG. 17B, content data is input clockwise via the broadband interface 105, and as conceptually shown in the lower part of FIG. 17B, the data is output clockwise to the decoder 102. In the example shown in FIG. 17B, the data in the hatched portion is actually stored content data. In parallel with outputting data to the decoder 102 as indicated by the arrow in the lower part of FIG. 17B, new data is input from the wideband interface 105 and stored in the direction indicated by the arrow in the upper part of FIG. 17B. In a normal state, the amount of data input and the amount of data output in the buffer memory 104 per unit time are the same, and the storage amount in the buffer memory 104 remains constant (more specifically, half the amount of storage of the buffer memory 104)

[0190] On the other hand, when the arrival time of the packet as data fluctuates in the case where the topology in the network system NT changes, the fluctuation can be absorbed by the buffer memory 104. In the case where the decoder 102 decodes the predetermined amount of data all at once or when the topology is disconnected for some reason, the buffer memory 104 functions to always store the predetermined amount of data so that the buffer memory 104 does not become It is empty, and the playback processing in the decoder 102 is not interrupted.

[0191] Referring again to FIG. 16, the timer 106 performs counting for detecting the stop of the relay function in any node in the network system NT, as described below.

[0192]

200580023946.9 The first decoder 102 decodes the content data output from the buffer memory 104 via the bus 109, outputs the image in the data to the CRT 108 that displays the image, and outputs the sound in the data via the speaker 107.

[0193] Next, the new node is connected to the network system NT. By using Fig. 18, the operations started and executed in the normal state including the new node and the published content are described all at once. FIG. 18 is a flowchart showing an example of a case where the node 3-1 is newly connected to the node 2-1 in the network system NT to obtain the network system NT as shown in FIG. 15 and the content is distributed to the node 3-1 . In the embodiment described below, it is assumed that the total storage capacity of the buffer memory 104 is 64 kilobytes corresponding to the data amount of 16 packets.

[0194] When the node 3-1 newly enters the network system NT by being physically connected to the node 2-1, first, the CPU 100 in the node 3-1 sets the buffer memory 104 in the node 3-1 (below each In the figure, the buffer memory 104 itself may be appropriately referred to as a "ring buffer). The CPU 100 in the node 3 sets the speed parameter (shown as "speed Reg" in the figure) representing the playback speed in the decoder 102 to be the same as the normal playback speed, and sets the speed parameter of the node as the data supply source The IP address is set to the node 2-1 on the upper layer (when the node 3-1 is connected to the node 2-1, the node 3-1 is used to obtain the IP address of the node 2-1). In order to calculate the address used to store data in the buffer memory 104, the CPU 100

2-1 Each of an input counter (16 bits) that counts the number of bytes of input data issued by the decoder 102 and an output counter (16 bits) indicating the amount of data reproduced by the decoder 102 are initialized to "zero" (step S101 ) Ο

[0195] The address used to store the data input to the buffer memory 104 is "the head address in the buffer memory 104 and the value of the input counter", and the address used to read the data to the decoder 102 is "buffer memory The head address in 104 + the value of the output counter".

[0196] After completing the necessary initialization processing, next, the CPU 100 in the node 3-1 refers to the topology table T in the table memory 103 and sends a start message for requesting the start of content data transmission to the node 2-1 (step S102 ) Ο

200580023946.9 p.

[0197] Next, the CPU 1 in the node 2-1 for receiving the start message (step SU5) determines whether the received message is a start message (step S116). Since the currently received message is a start message (step S116) The middle is Υ), so the CPU 1 returns the packet number of the data currently being replayed by the node 2-1 as the start packet number to the node 3-1 (step S117) ₀

[0198] When the node 3-1 obtains the starting packet number from the node 2-1, the node 3-1 stores it in the area of the corresponding packet number on the buffer memory 104 (step S103) and will be used to request actual content data The data request message is sent to the node 2-1 (step S104) ο The data request message includes information indicating the packet number of the data to be sent to the node 3-1 and the publishing speed (node

Parameter "Speed Reg" in 2-1).

[0199] The node 2-1 that has received the data request message (step S115) again determines whether the received message is a start message (step S116). Since the currently received message is a data request message (N in step S116), the node 2-1 determines whether the received message is a message requesting the topology table T (step S118).

[0200] The determination operation in step S118 (and the process of sending the topology table T from the node 2-1 in the case of "Y" in step S118) is performed to assume that it is a relay in any node in the network system NT. When the function is stopped, another node connected under the node whose relay function is stopped is prepared for the topology of the network system NT. At the current node

This operation is meaningless processing in the processing between 3-1 and the node 2-1 (therefore, naturally, the processing of sending the topology table T from the node 2-1 (step S119) is not performed).

[0201] Since the currently received message in the determination of step S118 is a data request message instead of a topology request message (N in step S118), it is next determined whether the received message is a data request message (step S120)- Since the currently received message is a data request message (Y in step S120), one packet of data is sent to node 3-1 at the playback speed specified in the data request message (currently IX) (via line L) (Step S121)_oWhen it is determined in step S120 that the message received from node 3-1 at this time is not a start message,

200580023946.9 When any one of the topology table request message and the data request message (N in step S120), the preset error message is returned to node 3-1 (step S122) 0

[0202] In parallel with these operations, the node 3-1 is set to start the count in the timer 106 in the node 3-1 in synchronization with the output of the data request message, and when the count becomes "0", the timing is generated Device interrupt command (step S105) o The node 3-1 waits until a predetermined time elapses in the count of the timer 106 (step S106). When the data from the node 2-1 does not arrive within the predetermined time (N in step S106), the timer interrupt instruction is executed, and the reconnection process is executed on the node 2-1.

[0203] On the other hand, when the data from the node 2-1 arrives within a predetermined time (Y in step S106), it is determined whether the arrived data is correctly transmitted (step S107) ο If the data is correctly transmitted (step S107) In S107, it is Y), the execution of the timer interrupt instruction is prohibited (step S108), and the amount of one packet of the received data is stored in the buffer memory 104. In connection with this operation, the value of the input counter and the packet number stored in the buffer memory 104 are only updated by one packet, and besides, the speed parameter is increased only by the current acceleration (set in the initialization process in step S101) (step S109 )=

[0204] Determine whether the amount of data stored in the buffer memory 104 and not output to the decoder 102 has become eight packets (that is, half the storage amount of the buffer memory 104) (step S110) Equivalent is less than eight When there are three packets (Y in step S110), the node 3-1 returns to step S104 to receive the next packet and repeat the above processing. On the other hand, when the amount of data stored in the buffer memory 104 becomes eight packets (N in step S110), the speed parameter and acceleration are reset to the initial values (step S111), and the data is output to the decoding The device 102 (step S112), and returns to the processing in step S104 to continue receiving subsequent data from the node 2-1.

[0205] By repeating the processing in steps S104 to S110, the speed issued from the node 2-1 is increased at the acceleration (0.2 times the initial value) at this time until the amount of data corresponding to eight packets is stored in the buffer To the memory 104, and the buffer memory 104 is at a high speed.

200580023946.9 is charged until the data reception becomes an error (Y in step S107). On the other hand, when an error occurs in the data reception (Y in step S107), the subsequent release speed is only 0.5 of the acceleration The times are reduced (step S113) to reliably perform data transmission, and then continue to publish.

[0206] In the processing of step S112, when the amount of data of eight packets is stored in the buffer memory 104 and the data is output to the decoder 102, the decoder 102 calculates according to the value of the output counter in the buffer memory 104 at this time. Acquire the address of the data output from the buffer memory 104 (step S125), decode and replay the data with only one packet (step S126), and increase the value of the output counter in the buffer memory 104 with only one packet (step S126) S127) ο The processing is repeated only by the amount of eight packets, thereby executing the data replay processing.

[0207] As described above, by performing the data distribution of the node 2-1 and the replay processing in the node 3-1, the data replay processing in the node 3-1 is performed while keeping the amount of data in the buffer memory 104 constant. .

[0208] Next, with reference to FIGS. 19 to 21, the processing performed in the case where the content relay function in the node 2-1 is stopped due to the following reasons, such as in the network system NT shown in FIG. 15 The power switch is cut off

[0209] In the network system NT according to the second embodiment, when the relay function in the node 2-1 is stopped due to the above-mentioned reason, as shown in FIG. 19, the node 3- which is connected to the initial node 2-1 1 and 3-2 automatically perform the topology reconstruction operation, which is used to connect to the node 1-1 located on the upper level of the node 2-1 via the line L, and continue the distribution of the content.

[0210] First, the general operation in the nodes 3-1 and 3-2 when the relay function in the node 2-1 is stopped as shown in FIG. 19 will be described.

[0211] When the relay function in the node 2-1 as shown in FIG. 19 is stopped, even after a predetermined time has passed in the processing of step S106 as shown in FIG. 18, the node 3-1 on the next level

The CPU 100 in each of 200580023946.9 and 3-2 (because the distribution in the normal state is continued, the processing described with reference to FIG. 18 is repeated) also cannot receive data from the node 2-1. When the data cannot be received even after the predetermined time has passed (N in step S106), the CPU 100 in each of the nodes 3-1 and 3-2 recognizes the The relay function is stopped and the topology is disconnected.

[0212] Afterwards, when the topology disconnection is recognized, the topology table T stored in the table memory 103 is referred to, and the topology is reconstructed so as to connect the nodes 3-1 and 3-2 to the higher ones via the newly formed line U. The node l-lo on the two levels of the hierarchy deletes the node 2-1 from the topology table T in the table memory 103 in each of the nodes 3-1 and 3-2, and simultaneously changes the level of the node 1-1 The information is updated to "1". After that, each of the nodes 3-1 and 3-2 sends a topology request message to the node 1-1 (refer to steps S118 and S119 in FIG. 18), and obtains a new topology table T from the node 1-1. According to the obtained topology table T, it is identified that the node located on the upper level of node 1-1 is node Ο-b, and at the same time the IP address and node number of node 0-1 whose layer information is "2" are added to In the topology table T (in each of the nodes 3-1 and 3-2), the topology reconstruction is completed.

[0213] After that, each of the nodes 3-1 and 3:2 requests the node 1-1 to send the packet after the packet whose packet number was obtained at that time (refer to step S104 in FIG. 18), and the node 1-1 receives Request and send subsequent data to nodes 3-1 and 3-2 as new destinations.

[0214] The changes in the buffer memory 104 in each of the node 1-1 and the nodes 3-1 and 3-2 during the reconstruction of the topology are described below with reference to FIGS. 20A to 20C.

[0215] As described above, when the relay function of the node 2-1 is stopped, the nodes 3-1 and 3-2 located on the next level of the node 2-1 cannot receive data from the node 2-1, so The amount of data in the buffer memory 104 in each of the nodes 3-1 and 3-2 is reduced. At the same time, the decoders 102 in the nodes 3-1 and 3-2 continue to read the data for playback processing from the buffer memory 104. Therefore, as shown in FIG. 20A, the data in each buffer memory 104 continues to decrease.

[0216]

200580023946.9 On the other hand, the node 1-1 located at the upper level of the node 2-1 cannot transmit data to the node located at the lower level, so the amount of data in the buffer memory 104 in the node 1-1 continues to increase , As shown in Figure 20B.

[0217] After the topology is reconstructed, the newly connected nodes 3-1 and 3-2 on the level below the node 1-1 must restore their buffer memory 104 to the normal state as soon as possible (that is, the data is stored in Half of the state). If it cannot continue to receive data from the upper node and the decoder 102 in nodes 3-1 and 3-2 continues to read data from the buffer memory 104, finally the buffer memory 104 becomes empty and the nodes 3-1 and 3-2 The playback processing in is interrupted.

[0218] As a result, in the second embodiment, the nodes 3-1 and 3-2 that are trying to achieve early recovery of the storage amount in their buffer memory 104 send a control signal (command) for increasing the issuance speed to the new The connected node l-lo. For example, the node 1-1 for receiving instructions publishes data to the nodes 3-1 and 3- at a publishing speed twice the normal playback processing speed in the nodes 3-1 and 3-2. The buffer memory 104 in 2 is as shown in FIG. 20C. Through this operation, the amount of storage in the buffer memory 104 is restored to a normal state almost at the same time as the time required to reconstruct the topology.

[0219] As a mode of increasing the posting speed, more specifically, the maximum value of the posting speed is determined by the transmission processing capacity of the CPU 100 in each node related to the so-called bandwidth (frequency band) of the lines L and L. In consideration of general redundancy, it is appropriate that the speed is approximately twice the above-mentioned normal playback processing speed.

[0220] As another mode of changing the publishing speed, for example, instead of doubling the publishing speed immediately, the node 1-1 can continuously increase the publishing speed at a predetermined rate until the following control is sent from the nodes 3-1 and 3-2 The control signal is used to notify the fact that the storage amount in the buffer memory 104 in each of the nodes 3-1 and 3-2 has reached a predetermined amount. Since the limit of the increase in the publishing speed depends on the output capacity of the node 1-1 and the bandwidth of the line 1/ used to connect the nodes 3-1 and 3-2, it is mastered by the exchange of necessary messages between the node and another controller Whether a packet from a node located at a higher level has reached a node located at a lower level. Increase the release speed to the highest allowable speed, and at a gradually increasing speed

200580023946.9 is the first time to transmit packets. In this way, the amount of storage in each buffer memory 104 can be restored in the shortest time. The node 3-2 transmits the packet to the lower nodes 4-1 and 4-2 at the same speed as the speed at which the packet is received from the node 1-1.

[0221] Next, the flowchart 21 is used to describe all at once when the relay function of the node 2-1 in the network system NT according to the second embodiment is stopped and the nodes 3-1 and 3-which are located on a lower level are stopped. 2 The operation performed when connecting to the node 1-1 again to reconstruct the topology of the network system NT as shown in FIG. 19. Next, the reconnection operation in the node 3-1 of the two nodes 3-1 and 3-2 connected to the node 2-1 will be described. In addition, the reconnection operation in node 3-2 is similarly performed.

[0222] Until the relay function of the node 2-1 is stopped, the processing shown in FIG. 18 is repeated in the node 3-1. When the data from the node 2-1 has not arrived even after the predetermined time has passed in the processing of step S106 as shown in FIG. 18, the node 3-1 determines the relay in the node 2-1 located on the higher level The function stops and the reconnection of the tree structure is started.

[0223] Specifically, as shown in FIG. 21, when the data from node 2-1 cannot be received within a predetermined time, a timer interrupt command is generated in node 3-1 (refer to step S105 in FIG. 18). ), from the topology table T in the table memory 103, obtain the node 1-1 located one level above the node 2-1, that is, the node whose layer information is "2" from the node 3-1

The IP address of 1-1 (step S130), and the information in the topology table T related to the node 2-1 is deleted. After that, the node 3-1 sends a topology table request message for acquiring the topology table T in the node 1-1 to the node 1-1 indicated by the IP address (step S131).

[0224] During the topology reconstruction process, in the node 1-1 located on the higher level, the operations performed in the node 2-1 shown in FIG. 4 are performed (steps S115 to S122 in FIG. 18). ) The same operation (steps S135 to S142 in Fig. 21). The type of the message sent from the node 3-1 is determined (steps S136, S137, and S140) and processing according to the determined message type (S139, S138, S141, and S142) is performed.

[0225]

200580023946.9 No. In the node 101 that has performed this processing, when the topology table request message is received from the node 3-1 (step S135) and it is determined that the message is the topology table request message (Y in step S137), the node 1-1 Send the topology table T stored in the table memory 103 to the node 3-1 (step S138) ο

[0226] The node 3-1 for receiving the topology table T (step S132) updates the existing topology table T through the topology table T acquired from the node 1-1 (step S133). More specifically, the node 3-1 identifies the node 0-1 and adds the IP address and the node number of the node 0-1.

[0227] After that, in order to restore the storage amount in the buffer memory 104 in the node 3-1 at high speed, the speed parameter is set to "1", the acceleration is set to 0.2, and the data request message is sent from the node 3-1 Send to node 1-1 (step S134). After that, the node 3-1 returns to step S1105 as shown in FIG. 18 and repeats the operations in steps S105 to S112 as a normal state.

[0228] Until the amount of one packet of data corresponding to the data request message is received from the node 1-1, the data in the buffer memory 104 is continuously decoded and continuously reduced (refer to FIG. 20A) = when the data starts from the node 1 -1 At the time of publishing (steps S140 and S141), the publishing data will gradually increase the publishing speed at the same time, until the amount of data corresponding to eight packets is stored in the buffer memory 104 (step S109 in FIG. 18). After the amount of data corresponding to each packet, the buffer memory 104 in the node 3-1 starts the function in the normal state (refer to FIG. 17B) ο

[0229] As described above, in the process of controlling the connection mode in the network system NT according to the second embodiment, when the relay function in any one node is stopped, another node capable of relaying content is retrieved. When continuing content distribution via another retrieved node, the distribution speed is made higher than the speed before the relay function is stopped. Therefore, it is possible to continue content processing in nodes belonging to the next level of the node whose relay function has stopped.

[0230] Due to the speed at which the content of another node that is newly connected will be published while continuing to publish

200580023946.9 is gradually increased to the upper limit speed, which is the maximum publishing speed, so that nodes belonging to lower levels can obtain necessary content more quickly. It is also possible to detect the amount of unreplayed data stored in the node's buffer after the relay function is stopped and the topology is reconstructed, and control the publishing speed to the highest speed based on the detected amount of unreplayed data time.

[0231] (B) Modification of the second embodiment A modification of the second embodiment will be described with reference to FIG. 22. Fig. 22 is a flowchart showing the operation of this revision.

[0232] In the second embodiment described above, when the relay function of the node 2-1 is stopped, another node (node 1-1) located on a higher level is retrieved and the distribution of content is resumed from this node. In the following revisions, multiple new nodes are retrieved and content publishing continues from multiple nodes at the same time.

[0233] The node 3-1 according to the revision cannot slave the node within the predetermined time as shown in FIG. 22A.

In the case of 2-1 receiving data, steps S130 to S133 shown in FIG. 21 are executed to update the topology table T in the node 3-1.

[0234] While receiving the data issued from the node 2-1, determine the storage amount (the number of packets) in the buffer memory 104 at this time and the required storage amount (eight packets) in the buffer memory 104 in the normal state. Whether the difference between is greater than two packets (that is, whether further data storage is necessary) (step S145) _oWhen the difference is greater than two packets (that is, when further data storage is necessary, Y in step S145), a new data request message is sent to node 1-1, the packet number to be received is updated, and the data The request message is sent to the node 0-1 located on the upper level of the node 1-1 (step S146) = it is determined that each of the data from one packet of nodes 1-1 and 0-1, that is, the total of two packets Whether the data has been received &lt;step S147) o When the data of two packets has not been received (N in step S147), the node 3-1 waits until the data of two packets is received. On the other hand, when two packets of data have been received (Y in step S147), the two packets of data are stored in the buffer

200580023946.9 In the memory 104, the input counter only updates two packets, the packet number to be received is updated (step S148), and the node 3-1 returns to step S145_O

[0235] On the other hand, when it is determined in step S145 that the difference is not greater than two packets (that is, further data storage is unnecessary, and it is N in step S145), it is determined whether the difference is greater than one packet (that is, , Whether it is unnecessary to supplement data urgently) (Step S149) ο When the difference is not greater than one packet (that is, the current storage amount in the buffer memory 104 is in a normal state) (N in Step S149), node 3-1 Return to step S111 in FIG. 4, and continue the normal receiving process.

[0236] On the other hand, when the difference is greater than one packet (that is, the current storage amount in the buffer memory 104 is close to the normal state and it is not necessary to urgently supplement data) (Y in step S149), the node 3-1 changes the new The data request message is sent to the node 1-1 (step S150) and waits until a predetermined time elapses in the count of the timer 6 in the node 3-1 (step S151) ₀If the data from the node 2-1 does not arrive within the predetermined time (N in step S151), the timer interrupt instruction is executed, and the data connection process is executed again on the node 1-1.

[0237] On the other hand, when the data from the node 1-1 arrives within a predetermined time (Y in step S151), the data amount of one packet received is stored in the buffer memory 104, and the value of the counter is input And the number of packets stored in the buffer memory 104 are updated by the amount of only one packet (step S152), and the node 3-1 returns to step S145.

[0238] When it is determined in step S147 that the data from node 0-1 cannot be received (Y in step S147), another node connected to node 0-1 (in the case of FIG. Node 1-2 or 1-3), send a data request message to another node, and check whether it can publish data.

[023] Through the above processing, as shown in FIG. 22B, data is input from multiple routers to the node

The buffer memory 104 in 3-1 can quickly restore the necessary storage capacity.

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[0240] In a manner similar to the node 3-1, the node 3-2 receives data from multiple routers and restores the necessary storage capacity. The nodes 4-1 and 4-2 below the node 3-2 located at the next level of the node 2-1 whose relay function has been stopped also receive data from multiple routers and quickly restore the necessary storage capacity. Nodes 4-1 and 4-2 below node 3-2 located at the next level of node 2-1 whose relay function has stopped may not receive data from multiple routers, while node 3-2 may be higher than The speed of the speed in the normal state in the second embodiment publishes data to the lower nodes 4-1 and 4-2.

[0241] In the above description, by connecting nodes located on different levels to nodes for publishing data, multiple paths to the nodes are formed. As a result, even in a case where the possibility of occurrence of a failure such as a stop of the relay function varies among different levels, sufficient redundancy can be reliably ensured.

[0242] (IV) Third Embodiment Now, referring to FIGS. 23 to 26, a third embodiment, which is another embodiment according to the present invention, will be described.

[0243] FIGS. 23 and 24 are block diagrams, each showing a schematic structure of the network system according to the third embodiment, and FIGS. 25 and 26 are flowcharts showing the operation of the network system.

[0244] In the above-mentioned second embodiment, the case where the relay function in the node stops during the reception of the content distributed via only one line L has been described. In the third embodiment described below, two paths are provided for one node in advance; the main path and the sub path, and the published content is received.

[0245] As shown in FIG. 23, in a manner similar to the second embodiment, the network system NT2 according to the third embodiment is formed by a tree structure whose vertex is the node 0-1 as the publishing device. The network system NT2 includes Nodes 1-1, 1-2, and 1-3 are used as nodes constituting the first level, nodes 2-1 and 2-2 are used as nodes constituting the second level, nodes 3-1, 3-2, and 3-3 And 3-4

200580023946.9 is used as the third level node, and nodes 4-1 and 4-2 are used as the fourth level node. The nodes are connected to each other via the main line LM as a wired circuit or a wireless circuit to be able to transmit/receive information to each other using the node 0-1 as a vertex. The specific example of each node is similar to that in the second embodiment.

[0246] In addition, in the network system NT2 according to the third embodiment, each node belonging to the second or lower hierarchy is connected to the node of the upper layer of the upper node to which the main line LM is connected by using the sub-line LS . In the normal publishing state, only the content published via the main line LM is provided to the playback processing in each node. The content distributed via the sub-line LS is temporarily received without being used for playback processing, and then distributed to another node located on the next level. Also, it is sufficient to receive the content distributed from the sub-line LS and distribute the content of the main line to the lower node.

[0247] The detailed structure of the node according to the third embodiment is different from the node according to the second embodiment (see FIG. 2) in that two table memories 103, two buffer memories 104, and two timers 106 are provided. , Each of them is one for the main line LM and the other for the sub-line LS. In a manner similar to the second embodiment, a CPU 100, a decoder 102, a broadband interface 105, a speaker 107, and a CRT 108 are provided. In addition, the topology table stored in each table memory of a node In T, unlike the second embodiment, an identifier is added to indicate whether the topology table is used for the topology table T of the main line LM or the topology table To of the sub-line LS.

[0248] For example, when a node belonging to the network system NT2 in the state shown in FIG. 23

When the relay function in 2-1 stops, the nodes 3-1 and 3-1 on the level below node 2-1

Each of 3-2 automatically connects the main line LM and the sub-line LS to the main line LM again, and the sub-line LS\ as shown in Figure 24, and continues to receive the published content. In this case, in FIG. 23, the node 3-1 is connected to the node 2-1 via the main line LM, and it is connected to the node 0-1 via the sub-line LS₀After the relay function in the node 2-1 is stopped, the node 3-1 connects the main line LM to the node 1-1, and the connection of the sub-line LS to the node 0-1 remains unchanged. On the other hand, in FIG. 23, the node 3-2 is connected via the main line LM

200580023946.9 is connected to node 2-1 and connected to node 1-1 via sub-line LS. After the relay function in the node 2-1 is stopped, the node 3-2 connects the main line LM to the node 3-1 at the same level, and the connection of the sub-line LS to the node 1-1 remains unchanged. In this way, the rules are strictly adhered to so that the main line LM is connected to the nearest node, and the sub-line LS is connected to a node located one level higher than the node to which the main line LM is connected.

[024] For the nodes 4-1 and 4-2 belonging to the fourth level, the node to which the sub-line LS is connected in FIG. 23 loses the relay function, so the main line LM remains unchanged and only the sub-line LS⁵Connect to the new node (in the case of Fig. 24, the sub-line LS, the connected node is node 3-1) ο

[0250] Next, the topology reconstruction operation performed in the nodes 3-1, 3-2, 4-1, and 4-2 in the case where the relay function in the node 2-1 is actually stopped will be described.

[0251] When the relay function in the node 2-1 is stopped as shown in FIG. 24, first, in the count time of the timer 106 described in the second embodiment, the node 3 of the next layer of the node 2-1 -1 and 3-2 start to connect to nodes located on the higher level of node 2-1. During the counting period of the timer 106, in the connected router, the node 3-1 stores the data issued from the node 0-1 in the buffer memory 4, and the node 3-2 stores the data issued from the node 1-1 In the buffer memory 4, and distribute the data to the lower nodes 4-1 and 4-2. After the topology is reconstructed, the data released from the main line LM is stored in the buffer memory 4, and the data released from the sub-line LS is released to the lower node.

[0252] The node 3-1 or 3-2 (node 3-1 in the case of FIG. 24) having a higher speed is connected to the node 1-lo. The node 3-1 connects the new main line LM to the node 1. -1, In addition, maintain the connection to the node 0-1 via the original sub-line LS, and receive the content published from the node 0-1 (backup distribution).

[0253] On the other hand, the node 3-2 that cannot be connected to the node 1-1 is connected to the node 3-1 currently belonging to the lower layer of the node 1-1 via the main line LM, while maintaining the connection with the node 1-1. original

200580023946.9 The first sub-line LS. In this case, node 3-2 can be directly reconnected to node 0-1. However, many nodes are currently connected to node 0-1, so the main line LM is actually connected to node 3-1 ο

[0254] For the nodes 4-1 and 4-2 located on the lower level, the result of disconnecting the original sub-line LSo, the nodes 4-1 and 4-2 inquire about the previous node belonging to the sub-line LS and the node to be newly connected to Node 3-2 of the layer. As a result, it can be recognized that a new main line LM is formed between nodes 3-2 and 3-1⁵, So that the node 4-1 or 4-2 that has asked the node 3-2 first forms a new sub-line LS to the node 3-1⁵[0255] Next, the operations performed when a new node is connected to the network system NT2 according to the third embodiment and the distribution of content is started and executed in a normal state including the new node will be described all at once with reference to FIG. 25. FIG. 25 is a flowchart showing a situation where the node 3-1 is newly connected to the node 2-1 in the network system NT2 to obtain the network system NT2 as shown in FIG. 23, and the distribution of content is performed to the node 3-1 example of.

[0256] In at least the following nodes among the nodes in the network system NT2 according to the third embodiment, the processing in the flowchart shown in the upper right part is always performed, which is another node via the main line LM or The node to which the sub-line LS is connected at a lower level.

[0257] Specifically, whenever a message is sent from a node at a lower level (step S170), the type of the message is sequentially determined (steps S171, S173, S175, S177, or S179).

[0258] When the received message is the start message (Y in step S171), the packet number of the data currently being replayed by the node is sent back as the start packet number (step S117).

[0259] When the received message is a topology data table request message (Y in step S173), in the topology table T currently provided for the node, according to the topology data table request message sent back to the node connected to The topology table T of the line type (main line or sub line) is sent back (step S174) ο

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[0260] When the received message is a data request message (Y in step S175), one packet of data is sent at the playback speed specified in the data request message (step S176).

[0261] When the received message is the support request information of a new node that inquires about the possibility of newly using the sub-line LS to publish data (Y in step S177), it is determined according to the association with another node that is publishing data at this time Is it possible to use sub-line L for publishing. If possible, reply with an "Allow" message. On the other hand, if it is not possible, reply "prohibited" message (step S178) =

[0262] t

When the received message is a mandatory connection request message (Y in step S179) for the mandatory release of data using the new sub-line LS, in a manner similar to the case of step S177, according to the data being released at this time The association of another node determines whether it is possible to use the sub-line LS for publishing. If possible, reply with an "Allow" message. On the other hand, if it is not possible, stop data release. The posting is to the following node (step S180), which is the layer information in the topology table T according to the type of line connected to the node that has sent the mandatory connection request information among the topology tables currently provided to the node The node that is "-1".

[0263] When the received message is not any of the above messages (N in step S179), a preset error message is sent back to the node that has sent the message (step S181)_o

[0264] In each node that continuously performs the above processing, the decoder 102 decodes the data from the node whose layer information is "1" in the topology table T corresponding to the main line LM and outputs the decoded data. data. On the other hand, data from a node whose layer information is "1" in the topology table T corresponding to the sub-line LS is distributed to another node located on a lower level without being decoded.

[0265] In the network system NT2 operating in this state, when the node 3-1 newly enters the network system NT2 by physically connecting to the node 2-1, first the CPU in the new node 3-1

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100 Set the two buffer memories 104 in the node 3-1 (used for the main line LM and the sub-line LS), set the IP address of the node indicating the data supply source, and set the node 0-1 on the upper level Set on the sub-line LS (when the node 3-1 is connected to the node 2-1, the node 3-1 obtains the IP addresses of the two nodes from the node 2-1). In order to calculate the address at which data is stored in each buffer memory 104, the input counter 1 (16 bits), the input counter 2 (16 bits), and the output counter 1 (16 bits) are initialized to "0". The input counter 1 counts the number of bytes of received data issued from the node 0-1 via the main line LM. The input counter 2 counts the number of bytes of received data issued from the node 0-1 via the sub-line LS. The output counter shows the amount of data reproduced by the decoder 102. In addition, at this time, a buffer address indicating "ring buffer 1" (in FIGS. 25 and 26, appropriately expressed as "ring buffer ADR") is set in the buffer memory 104 corresponding to the main line LM (step S160) .

[0266] After completing the necessary initialization processing, the CPU 100 in the node 3-1 refers to the topology table T in the table memory 3, and sends a start message for requesting the nodes 2-1 and 0-1 to start content data Transmission (step S161) ο

[0267] Next, the CPU 100 in the nodes 2-1 and 0-1 that have received the start message sends the packet number of the data currently replayed by the nodes 2-1 and 0-1 to the node as the start packet number 3-1 (Step S172).

[0268] The node 3-1 obtains the starting packet number from the nodes 2-1 and 0-1, stores it in the corresponding packet number area on the buffer memory 104 corresponding to the line (step S162), and will use it for the request The data request message of the actual content data is sent to the nodes 2-1 and 0-1 (step S163). The data request information includes the packet number information of the data to be sent from nodes 3-1 and 2-1 (replay processing) and node 0-1 (used to immediately publish data to a lower level).

[026] The nodes 2-1 and 0-1 that have received the data request message (in step S170 and "Y" in S175) are at the playback speed specified in the data request message (via the main line LM and sub Line LS) sends the data amount of one packet to node 3-1 (step S176).

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[0270] In parallel with this operation, node 3-1 is set to output a data request message, and at the same time, counting is started by the timer in node 3-1, and a timer interrupt instruction is independently generated when the count becomes "0" (Step S164) ο Node 3-1 waits until a predetermined time elapses in the count of each timer 106 (Step S165) ο When data from nodes 2-1 and 0-1 does not arrive within the predetermined time (N in step S165), the node 3-1 executes the timer interrupt instruction, and executes the connection process again on the nodes 2-1 and 0-1.

[0271] On the other hand, when the data from the nodes 2-1 and 0-1 arrive within a predetermined time (Y in step S165), the node 3-1 prohibits execution of the timer interrupt instruction (step S166), and sets The amount corresponding to one packet of received data is stored in the buffer memory 104. Along with this processing, the values of the input counters 1 and 2 and the packet number stored in the buffer memory 104 are only updated by the amount of one packet.

[0272] The node 3-1 determines whether the amount of data stored in each buffer memory 104 and not yet output to the decoder 102 becomes four packets (that is, 1/4 of the storage amount of the buffer memory 104) (step S168). When the amount is less than four packets (Y in step S168), the node 3-1 returns to step S163 to receive subsequent packets from the nodes 2-1 and 0-1, and repeats the above processing. On the other hand, when the amount of data stored in each buffer memory 104 becomes four packets (N in step S168), only the data acquired via the main line LM is output to the decoder 102 (step S169), And it returns to the processing in step S163 to receive the following data from the nodes 2-1 and 0-1.

[0273] In the process of step S169, when the data amount of four packets is stored in the buffer memory 104 corresponding to the main line LM and is output to the decoder 102, the decoder 102 only passes the four packets Repeat the following operations to perform the data playback process. In these operations, the decoder 102 obtains the buffer address of the buffer memory 104 and the address of the data output from the buffer memory 104 according to the value of the output counter in the buffer memory 104 indicated by the buffer address (step S182). The data is decoded and replayed in one packet (step S183), and the value of the output counter in the buffer memory 104 only increases

200580023946.9 add the first packet (step S184) ο

[0274] By performing the data distribution of the slave node 2-1, the replay processing in the node 3-1, and the distribution of the slave node 0-1 using the sub-line LS as described above, the data reproduction in the node 3-1 is performed Processing while keeping the amount of data in each buffer memory 104 unchanged.

[0275] Next, referring to FIG. 26, the content relay function in the node 2-1 will be described in detail, and the execution of the processing is stopped due to reasons such as the power switch being turned off in the network system NT2 as shown in FIG. 23.

[0276] In the network system NT2 according to the third embodiment, when the relay function in the node 2-1 is stopped due to the above-mentioned reason, as shown in FIG. 24, the node 3-1 connected to the original node 2-1 And 3-2 and nodes 4-1 and 4-2 automatically perform topology reconstruction operations, and continue to publish content through the topology in the pattern as shown in FIG. 24.

[0277] When the relay function in the node 2-1 as shown in FIG. 25 is stopped, even after a predetermined time has elapsed in the processing of step S165 as shown in FIG. 25, the node 3-1 located on the next level And the CPU 100 in each of 3-2 (because the distribution in the normal state shown in FIG. 25 is continued, the processing described with reference to FIG. 25 is repeated) also cannot receive data from the node 2-1. When the data cannot be received even after the predetermined time has passed (N in step S165), the CPU 100 in each of the nodes 3-1 and 3-2 recognizes the The relay function is stopped and the topology is disconnected.

[0278] After that, when the topology disconnection is recognized, the topology table T stored in the table memory 103 is referenced to execute the interrupt instruction as shown in FIG. 26, and the topology is reconstructed as shown in FIG. 24.

[0279] Specifically, as shown in FIG. 26, when the interrupt instruction is executed, it is determined whether the timer 106 that has passed the predetermined time is the timer 106 corresponding to the main line LM (indicated as "timing" in FIG.Device1") (Step S190). When it is the timer 106 corresponding to the main line LM (Y in step S190), the value of the cache address is changed to indicate the

200580023946.9 The value of the buffer memory 104 corresponding to the sub-line LS to set the buffer memory 104 corresponding to the sub-line LS to output data to the buffer memory 104 of the decoder 102 (step S191).

Next, in the main line LM, the topology table request message corresponding to the main line LM is sent to the node whose layer information value is "2" (node 1-1 in the case of FIG. 24) (steps S192 and S194), and obtain the topology table T corresponding to the main line LM from the topology table T in the node (step S195) =

[0280] By using the obtained topology table T, the topology table T in the nodes 3-1 and 3-2 corresponding to the main line LM is updated (step S196).

[0281] Next, the new node support request message queries the node whether the sub-line LS can be connected to the node whose layer information is "2" in the updated topology table T (node 0-1 in the case of FIG. 24). ) (Step S197) ο

[0282] Check whether the reply of the new node support request message is "allowed" (step S198). If it is "allowed" (y in step S198), the node to which the sub-line LS is connected before the relay function is stopped The IP address of the main line LM is rewritten as the IP address of the node to which the main line LM is currently connected, and the IP address of the node to which the sub-line LS is newly connected (node 0-1 in the case of FIG. 24) is used as the current ( New) The IP address of the node whose layer information is "2" in the topology table T corresponding to the sub-line LS is written into the topology table T (step S199) ο

[0283] On the other hand, when it is determined in step S198 that the reply of the new node support request message is "prohibited" (N in step S198), a mandatory connection request message is sent to the initial connection of the sub-line LS. Node 1-1 on the next level of node 0-1 (step S200)_o

[0284] When the node 1-1 receives the mandatory connection message and the sub-line LS can be connected in the node 1-1, the connection is allowed in the node 1-1, and the topology table T in the node 3-1 is Update (step S201). When it is not possible, the distribution of data from node 0-1 to node 1-1 is stopped. The node 1-1 to which the data is stopped executes the above processing, thereby reconstructing

200580023946.9 Topological structure.

[0285] On the other hand, when it is determined in step S190 that the interrupt instruction (N in step S190) is executed in the timer 106 corresponding to the sub-line LS, the relay function of the node 2-1 at the upper level The main line LM operates. Therefore, the topology table request message corresponding to the main line LM is sent to the node 2-1 (steps S193 and S194), the topology table T in the node 2-1 is obtained (step S195), and the processing of step S196 and subsequent steps are performed .

[0286] As described above, in the network system NT2 of the third embodiment, the main line LM and the sub-line LS are formed to connect a plurality of nodes to one node. The data distributed via the main line LM is used for playback processing in this one node or the like and distributed to other nodes belonging to a lower hierarchy. On the other hand, the data distributed via the sub-line LS is used to distribute to other nodes belonging to a lower level. By connecting multiple lines to each node, when preparing to stop the relay function in any node, redundancy can be increased, and it is possible to prevent the replay processing etc. in nodes belonging to lower levels from being stopped.

[0287] When the relay function in a node belonging to a higher level is stopped on the main line LM to a node, the data distributed via the sub-line LS is switched to be used for replay processing and the like, so as to be in the one node The replay processing and other classes are not interrupted.

[0288] In addition, when data posted via the sub-line LS is switched for use in playback processing or the like, any node belonging to a higher hierarchy is retrieved, and a new node is formed by connecting to the retrieved node. The sub-line LS. Therefore, even when the sub-line LS is used as the main line LM, a new sub-line LS is formed, and redundancy can be ensured and maintained.

[0289] In addition, when the relay function in a node belonging to a higher level stops on a sub-line LS± to a node, any node belonging to a higher level is retrieved, and is retrieved by connecting to the To form a new sub-line LS. Therefore, even when the relay function in the node on the sub-line LS is stopped, a new sub-line LS is formed, and redundancy can be ensured and maintained.

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[0290] Since a node of a higher level is retrieved so that another node on the level to which the one node belongs is included in the new main line LM, the supply of posted information can be retrieved via the node at the same level.

[0291] In each of the foregoing embodiments, as a method for detecting the stop of the relay function in any node, in addition to the above method, the node can periodically detect whether there is a response to a higher or lower level node . For example, when the relay function of the node 2-1 itself in each embodiment is stopped, the stop may be notified to the node 101 at a higher level, or the nodes 3-1 and 3-2 at a lower level.

[0292] The series of connection mode control processing described above may also be performed under the control of another server device located outside the network system NT or NT2. In this case, the server device has the connection mode information of the nodes in the network system NT or NT2. By sending the query from the nodes 3-1 and 3-2 to the server device, the node 1-1 located on the upper level of the node 2-1 whose relay function is stopped is identified.

[0293] In addition, the decoder 102, CRT 108, and the like for replaying content may also be configured to connect a replay device or the like at a location other than a node via another network.

[0294] In addition, it is also possible to record the program corresponding to the flowcharts of FIGS. 18, 21, 22, 25, and 26 on an information recording medium such as a floppy disk or hard disk, or obtain and record the program via the Internet or the like, and The program is read and executed by an ordinary computer, so that the computer functions as the CPU 100 according to these embodiments.

Industrial applicability

[0295] As described above, the present application can be applied to the field of distributing content by using a network system having a tree structure. In particular, when the present invention is applied to a content distribution field that is not convenient for distribution interruption, such as movies, music, etc., which are played in real time, obvious effects can be obtained.

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