Packet generating method, communication method, packet processing method, and data structure

The present invention relates to a packet generation method, a communication method, a packet processing method, and a data structure capable of grouping networks.

Conventionally, there is a method of introducing a VLAN switch as a means of grouping IP networks. FIG. 1 shows a network constructed by the VLAN switch 103. The case where the communication device A and the communication device B are in the same group 1 and the communication device C and the communication device D are in the same group 2 is shown. In this method, the VLAN switch 103 analyzes the IP packets flowing in the network and delivers the IP packets according to the rules set in advance in the VLAN switch 103. This makes it possible to manage the network by arranging the communication devices that do not want to communicate with each other in different groups among the various communication devices connected in the LAN 104 (for example, Patent Document 1). reference).<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2000-134207 (Page 10, Fig. 1)</text></patcit>

<p> However, when introducing the VLAN switch 103 as described above, all the communication devices existing in the network are investigated in advance, and the physical wiring of which port of the VLAN switch 103 to connect each communication device is considered. There is a need to. Further, when changing the group to which the communication device belongs, it is necessary to consider the setting change of the VLAN switch 103 and the change of the wiring related to the entire network, and there is a circumstance that maintenance is very troublesome. An object of the present invention is to provide an IP packet generation method, a communication method, a packet processing method, and a data structure that realizes network grouping without introducing a VLAN switch.</p>

<p> The packet generation method of the present invention is a method of generating an IP packet including an IP data unit and an IP header including an option area, and an arbitrary data area is added after the final position display indicating the final position of the option area. .. Further, the communication method of the present invention transmits an IP packet generated by the packet generation method of the present invention. Further, the data structure of the present invention is a data structure of an IP packet including an IP data unit and an IP header including an option area, and the option area includes an arbitrary data area following the option final position display. According to these configurations, a group number that defines a combination of a plurality of communication partners in this data area by using an IP packet generated by adding an arbitrary data area after the value indicating the final position of the IP header option. Can be added, and network grouping can be realized without introducing a VLAN switch.</p>

<p> According to the present invention, by using an IP packet generated by adding an arbitrary data area after the value indicating the final position of the IP header option, a group number that defines a combination of a plurality of communication partners is set in this data area. It can be assigned, and network grouping can be realized without introducing a VLAN switch.</p><p> Also, when changing the group number to which it belongs, it is sufficient to change the group number setting of the communication device whose group number you want to change, without changing the settings or wiring related to the entire network like the VLAN switch. There is an advantage. Further, by managing the group number by each communication device, it is possible to communicate with all the communication devices belonging to the same group at once. Furthermore, control commands can be added, and it becomes possible to remotely control a designated communication device. Furthermore, by combining these, it is possible to issue control commands to all communication devices belonging to the same group at once. For example, when the home network is divided into a home appliance group and an AV device group, the AV device group It has the effect of improving the convenience of the network, such as resetting only the device. In addition, by retaining the group information of communication packets, it is possible to check the communication devices of the same group existing in the network, and by notifying the network of the group to which you belong at startup, the group information is immediately available. Can also be updated. Further, in a home network or the like, it is common to automatically assign an IP address in a DHCP environment, and in an environment where the IP address changes each time, a VLAN switch cannot handle it, but according to the present invention. Network grouping in a DHCP environment is also possible, and in the existing home network environment, not only is it more effective than the introduction of a VLAN switch in terms of network grouping, but it is also possible to implement network control functions. Will be.</p>

Hereinafter, embodiments of the present invention will be described. FIG. 2 shows the network constructed by the present invention. The case where the communication device A and the communication device B are in the same group 1 and the communication device C and the communication device D are in the same group 2 is shown. Further, each communication device A, communication device B, communication device C, and communication device D in FIG. 2 performs packet generation and communication according to the present invention, and also processes received packets.

FIG. 3 shows the format of the IP packet used for transmission / reception in the first embodiment, and includes an area 304 for storing the group number. For the group number, it is necessary to specify the size of the storage area in advance. For example, when the size is 4 bytes, when storing the group number 5, "0x00000005" is stored in the group number area 304.

The value to be set as an option is specified for the IP header option 301, and if an arbitrary value is simply stored there, the communication device that receives the packet may malfunction. The method of describing options is specified in the IP header option, and after storing various option values 302, display 303 (option type value 0x00, 1 byte length) indicating the final position of the description of the option area is stored. That is, even if a value is stored after the value indicating this final position, it is not referenced. By utilizing this, by storing an arbitrary value after the value indicating the final position and sending out an IP packet, it is possible to add information without affecting the existing communication device. Further, since the IP header option 301 is specified to be in units of 4 bytes, if the length is not 4 bytes, a padding 305 is inserted to adjust the length.

FIG. 4 is a flowchart of the transmission process in each communication device in the first embodiment. The operation of the transmission process will be described. First, the communication device generates data to be transmitted to the network (step 401). After that, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 402).

As the value to be stored in the IP header option, specify that the group number should be stored after the option final position display value 0x00 (step 403). After that, it is generated as a network packet by TCP / IP transmission processing (step 404), the generated IP packet is sent to the network (step 405), and the process ends.

FIG. 5 is a flowchart of reception processing in each communication device in the first embodiment. The operation of the reception process will be described. First, it receives an IP packet from the network (step 501). After that, the IP header option of the received IP packet is referred to, and the group number stored after the option final position display value 0x00 is acquired (step 502).

Then, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 503). The group numbers are compared (step 504), and if the group numbers match, TCP / IP reception processing is performed (step 505), the received data is acquired (step 506), and the process ends. If the group numbers do not match, the received frame is discarded (step 507) and the process ends.

With the above configuration, it is possible to group communication devices that do not want to communicate with each other by performing network communication only between communication devices of the same group and not performing network communication with communication devices of different groups.

Embodiment 2 of the present invention will be described with reference to FIG. The second embodiment is the same as the first embodiment in the packet transmission processing and the packet format to be used, but realizes a function different from that of the first embodiment by changing the control of the reception processing.

FIG. 6 is a flowchart of the reception process according to the second embodiment in each communication device. The operation of the reception process will be described. First, it receives an IP packet from the network (step 601). After that, the IP header option of the received IP packet is referred to, and the group number stored after the option final position display value 0x00 is acquired (step 602).

Then, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 603). The group numbers are compared (step 604), and if the group numbers match, only the minimum check processing that simplifies the normal TCP / IP reception processing is performed (step 605), and the received data is acquired (step). 606), finish. Here, examples of the minimum check processing include checksum processing above the IP layer and not accepting fragmented packets. If the group numbers do not match, normal TCP / IP reception processing is performed (step 607), received data is acquired (step 606), and the process ends.

With the above configuration, communication performance can be improved only between communication devices of the same group. This is effective when the same group is configured as a group of communication devices that can be trusted by each other, and if it is received from the same group, unauthorized access such as data falsification or packets containing unintended parameters It is considered that there is no reception, and it is possible to omit the check process for them.

FIG. 7 shows the format of the IP packet used for transmission / reception in the third embodiment, and includes an area 705 for storing a control command command. The value to be stored as a control command command must be specified. As an example, there is a method of storing as an ASCII character string such as "reset" and indicating the end of the command with "0x00" (hereinafter, \ 0). Called the end). In this case, the value actually stored in the control instruction command area 705 is 0x726573657400. The IP header option 701, various option values 702, option final position display 703, group number area 704, and padding 706 are the same as those described in the first embodiment.

FIG. 8 is a flowchart of the transmission process in each communication device in the third embodiment. The operation of the transmission process will be described. First, the communication device generates data to be transmitted to the network (step 801). After that, the group number to which one belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 802).

Then, the control command to be executed by the communication destination is generated (step 803). As the value to be stored in the IP header option, specify that the group number is stored after the option final position display value "0x00" and the control command generated in step 803 is stored after that (step 804). Generated as a network packet by TCP / IP transmission processing (step 805). The generated IP packet is sent to the network (step 806), and the process ends.

FIG. 9 is a flowchart of reception processing in each communication device in the third embodiment. The operation of the reception process will be described. First, it receives an IP packet from the network (step 901). After that, the IP header option of the received IP packet is referred to, and the group number stored after the option final position display value 0x00 is acquired (step 902).

Then, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 903). The group numbers are compared (step 904), and if the group numbers do not match, the received frame is discarded (step 909), and the process ends. If the group numbers match, check that the control command command is added after the group number by checking if there is a character string terminated by \ 0 (step 905), and if it is added, check it. Command processing is executed (step 906), TCP / IP reception processing is performed (step 907), received data is acquired (step 908), and the process ends.

With the above configuration, it is possible to execute a special control command command while performing network communication only between communication devices of the same group. The control command command may be, for example, a device reset command, a setting change command, a group number change, or the like.

FIG. 10 is a flowchart of the transmission process in each communication device in the fourth embodiment. The operation of the transmission process will be described. First, the communication device generates data to be transmitted to the network (step 1001). After that, the group number to which one belongs is acquired from the setting value of the communication device stored in advance in the external memory or the internal memory (step 1002).

As the value to be stored in the IP header option, specify that the group number should be stored after the option final position display value 0x00 (step 1003). Specify the destination for IP broadcast (step 1004). Generated as a network packet by TCP / IP transmission processing (step 1005). Send the generated IP packet to the network (step 1006) and end. The reception process is the same as that of the first embodiment.

With the above configuration, communication can be performed by transmitting one packet to all the communication devices belonging to the same group.

FIG. 11 is a flowchart of the transmission process in each communication device in the fifth embodiment. The operation of the transmission process will be described. First, the communication device generates data to be transmitted to the network (step 1101). After that, the group number to which the user belongs is acquired from the setting value of the communication device stored in advance in the external memory or the internal memory (step 1102).

As the value to be stored in the IP header option, specify that the group number should be stored after the option final position display value "0x00" (step 1103). Generate a control command that you want the communication destination to execute (step 1104). As the value to be stored in the IP header option, specify that the group number is stored after the option final position display value "0x00" and the control command generated in step 1104 is stored after that (step 1105).

Then, the destination is specified for IP broadcast (step 106). Generated as a network packet by TCP / IP transmission processing (step 1107). Send the generated IP packet to the network (step 1108) and end. The reception process is the same as in the third embodiment.

With the above configuration, it is possible to communicate with all communication devices belonging to the same group by transmitting only one packet and execute a control command. For example, by designating a device reset or a change of a group number as a control command, it is possible to control a device reset of a specific group as a whole or a change of a group number.

FIG. 12 is a flowchart of reception processing in each communication device in the sixth embodiment. The operation of the reception process will be described. First, it receives an IP packet from the network (step 1201). After that, the IP header option of the received IP packet is referred to, and the group number stored after the option final position display value 0x00 is acquired (step 1202).

Then, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 1203). Compare the group numbers (step 1204), and if the group numbers match, the data is received from the communication device of the same group, so TCP / IP reception processing is performed normally (step 1208), and the received data is acquired (step 1209). ),finish.

If the group numbers do not match, determine whether to perform an IP check (step 1205). This is a value that can be changed by the setting value stored in the external memory or the internal memory, and whether or not to perform the IP check is determined in advance with or without the IP check as the setting value of the communication device in the external memory or the internal memory. It should be possible to set it.

If there is no IP check, TCP / IP reception processing is performed normally (step 1208), received data is acquired (step 1209), and the process ends. If there is an IP check, the source IP address set in the IP header of the received frame is referred to, and the AND value of the source IP address and the subnet mask value set in the own device and the own device Compares the network part of the IP address of, and if they do not match, it is considered to be received from the WAN network.

Since reception from the WAN network is not subject to group control, TCP / IP reception processing is normally performed (step 1208), received data is acquired (step 1209), and the process ends. If it is not received from the WAN network, discard the received frame (step 1207) and exit. The transmission process is the same as in the first embodiment.

With the above configuration, it is possible to normally perform communication with the Internet while performing group control. If you do not want to communicate with the Internet, you can store the setting without IP check in the external memory or internal memory so that it will not receive from the WAN network. It is possible to build a completely secure network closed in the same group. This is effective as a means when you do not want to be accessed from the Internet temporarily by operating with the setting with IP check and operating with the setting without IP check when necessary.

FIG. 13 is a flowchart of reception processing in each communication device in the seventh embodiment. The operation of the reception process will be described. First, it receives an IP packet from the network (step 1301). Refer to the IP header option of the received IP packet, and acquire the group number stored after the option final position display value 0x00 (step 1302).

Then, the group number to which the user belongs is acquired from the set value of the communication device stored in advance in the external memory or the internal memory (step 1303). Compare the group numbers (step 1304), and if the group numbers match, refer to the source IP address set in the received IP packet and store it as the IP address of the communicator in the same group in the network. (Step 1305).

Since the received IP packet is received from a communication device of the same group, the TCP / IP reception process is normally performed (step 1306), the received data is acquired (step 1307), and the process ends. If the group numbers do not match, the received frame is discarded (step 1308) and the process ends. The transmission process is the same as that in the third embodiment.

With the above configuration, it is possible to retain and store the IP address of the other party who has communicated in the past within the same group. For example, if a command to change the group number to another value is specified as a control command, this command is sent to a communication device in the group that has communicated so far, and the command is transferred to another group. By making it possible, operations such as forming a temporary virtual private group become possible. In addition, as a countermeasure when the communication device that holds the IP address information shuts down and does not exist from the network, the retained information can be deleted after a certain period of time.

FIG. 14 is a flowchart of the group number notification process in each communication device in the eighth embodiment. The group number notification process will be described. First, in order to notify the network of the group number, empty data is generated as transmission data (step 1401). Obtain the group number to which you belong from the set value of the communication device stored in advance in the external memory or internal memory (step 1402).

As the value to be stored in the IP header option, specify that the group number should be stored after the option final position display value 0x00 (step 1403). Specify the destination for IP broadcast (step 1404). Then, it is generated as a network packet by TCP / IP transmission processing (step 1405). The generated IP packet is sent to the network (step 1406), waits for a certain period of time for retransmission (step 1407), and the process returns to step 1401 again.

The eighth embodiment is an effective means in the environment in which the seventh embodiment is implemented. Although it is possible to acquire group information by operating only the seventh embodiment, the eighth embodiment has the effect of enhancing the real-time property of sharing the group information. By performing the eighth embodiment immediately after the communication device is activated, it is possible to immediately notify all the communication devices of the same group of their own group number. Further, since the retransmission is performed, the group number can be reliably notified to the communication device connected later.

With the above configuration, the IP addresses of all communication devices in the same group as you existing in the network can be known, for example, by saving it as log information or displaying it if it is a device that can display the screen. Group information can be obtained automatically without having to bother to check the settings of all communication devices. Since the eighth embodiment is a process of repeating retransmission, there is a possibility of applying a load on the network, and the time for waiting for retransmission is set to an appropriately long time (for example, a cycle of seconds or more such as every 60 seconds). Is preferable.

By applying the present invention, each communication device can recognize the group number and perform transmission processing and reception processing. Therefore, it is possible to configure a system in which LAN networks are grouped without introducing a VLAN switch. it can. In grouping, each communication device recognizes its own group number and operates, so the communication device that wants to change the group number without changing the settings or wiring related to the entire network like the VLAN switch. There is an advantage that it is only necessary to change the group number setting. In addition, the function of accepting only access from the same group as oneself and the function of IP broadcasting a packet with a group number to the network make it possible to transmit data only to communication devices of the same group. This is an effective function for broadcasting video only to the same group. For example, it can be used when broadcasting surveillance images from an IP network camera in real time. Furthermore, the function of adding a control command command to the packet makes it possible to remotely control the designated communication device. If this is distributed to the entire group by IP broadcast, for example, if the home network environment is divided into a home appliance group and an AV device group, and a power-off control command is sent to the AV device group, the refrigerator It has the effect of improving the convenience of the network, such as turning off the power of only the AV equipment group without turning off the power of the home appliances group that you do not normally want to turn off. In addition, the function to retain group information of communication packets makes it possible to check and manage the communication devices of the same group existing in the network, and the function to notify the network of one's own group at startup instantly. You can also update the group information. Also, in home networks, etc., it is common to automatically assign an IP address in a DHCP environment, and in an environment where the IP address changes each time, the VLAN switch cannot handle it, but this is the main issue.

<figref num="1">Diagram showing the network constructed by the VLAN switch</figref><figref num="2">The figure which shows the network constructed by this invention</figref><figref num="3">The figure which shows the format of the IP packet used in Embodiment 1.</figref><figref num="4">The figure which shows the flow of the transmission processing in Embodiment 1.</figref><figref num="5">The figure which shows the flow of the reception processing in Embodiment 1.</figref><figref num="6">The figure which shows the flow of the reception processing in Embodiment 2.</figref><figref num="7">The figure which shows the format of the IP packet in Embodiment 3.</figref><figref num="8">The figure which shows the flow of the transmission processing in Embodiment 3.</figref><figref num="9">The figure which shows the flow of the reception processing in Embodiment 3.</figref><figref num="10">The figure which shows the flow of the transmission processing in Embodiment 4.</figref><figref num="11">The figure which shows the flow of the transmission processing in Embodiment 5.</figref><figref num="12">The figure which shows the flow of the reception processing in Embodiment 6.</figref><figref num="13">The figure which shows the flow of the reception processing in Embodiment 7.</figref><figref num="14">The figure which shows the flow of the transmission processing in Embodiment 8.</figref>

Code description

101,201 WAN 102,202 Router 103 VLAN Switch 104,204 LAN 301,701 IP Header Option 302,702 Various Option Values 303,703 Option Final Position Display 304,704 Group Number Storage Position in IP Header Option 305,706 Padding 401,801,1001,1101 Transmission Data Generation Processing 402,802,1002,1102,1402 Group number read processing of own device stored in internal memory 403,1003,1103,1403 Processing that specifies that the group number is stored in the IP header option 404,805,1005,1107,1405 TCP / IP transmission processing 405,806,1006 , 1108,1406 IP packet transmission process to network 501,601,901,1201,1301 IP packet reception process from network 502,602,902,1202,1302 Group number acquisition process in IP header option of received frame 503,603,903,1203,1303 Group number acquisition process set in own device 504,604,904,1204,1304 Receive frame group number determination process 505,607,907,1208,1306 TCP / IP reception process 506,606,908,1209,1307 Received data acquisition process 507,909,1207 , 1308 Packet discard processing 605 TCP / IP processing with simplified check function 705 Control command command storage position in IP header option 803,1104 Processing that specifies that control command commands are stored in IP header option 804,1105 Group Processing to specify the number and control command command as an option 905 Processing to specify the control instruction command of the received frame 906 Processing to execute the control instruction command 1004,1106,1404 Processing to specify to be transmitted by IP broadcast 1205 Setting the presence or absence of IP check Processing to determine 1206 Processing to determine packets coming from the WAN from the source IP address 1305 Process of holding the source IP address 1401 Process of generating empty data to notify the group number 1407 Process of waiting for retransmission of the group number notification packet