Communication distribution control method and controller

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a communication distribution control method, and more particularly, relates to a communication distribution control method and a control device in which a server that receives a communication connection request from a client side distributes the communication to any of a plurality of other servers on the Internet, for example. ..

【0002】

[Problems to be solved by conventional techniques and inventions]

The present invention is intended for, for example, a communication system having an object request broker (ORB) mechanism. The ORB is a mechanism for calling methods and functions across computers, that is, nodes, in a distributed computing environment. For example, it is called CORBA (Common Object Request Broker Architecture). It is used in one of the standards for communication paths between distributed objects. This standard is an industry standard established by the Object Management Group (OMG) and is widely adopted by various vendors.

【0003】

ORB is a method in which a client's request is transmitted to the object to perform an operation between the client and the object, and when the object returns a result, the result is returned to the client.

【0004】

FIG. 13 is an explanatory diagram of a conventional example of a CORBA communication method by HTTP tunneling in which a client requests processing from a CORBA application (AP) server that processes an object and receives the result.

【0005】

In FIG. 13, it is assumed that the personal computer (PC) 101 that requests the processing and the CORBA AP server 104a that executes the requested processing are connected via the Internet.

【0006】

In general, communication using IIOP (Internet Inter ORB Protocol), which is an inter-object communication protocol over TCP / IP defined by OMG, is the most efficient between the client-side PC and the CORBA application server. It can communicate with remote servers even if the program is written in a different language.

【0007】

However, when communicating between the client and the CORBA AP server via the Internet, it is generally necessary to use the HTTP tunneling method that converts to the IIOP protocol and communicates. Therefore, in general, it is necessary to perform protocol conversion from IIOP to HTTP on PC101, and to perform protocol conversion from HTTP to IIOP on the relay server in the previous stage of CORBA AP server 104a.

【0008】

In FIG. 13, the client-side PC101 requests one session, that is, the processing corresponding to the business to the CORBA AP server 104a. The business of this session consists of, for example, four stages, and in response to each stage, a processing request to the CORBA AP server 104a and communication to receive a response to it are required, and this communication corresponds to each stage. It shall be performed intermittently between PC101 and CORBA AP server 104a.

【0009】

Upon the start of the session, the client-side PC 101 gives a communication connection and processing request to the CORBA AP server 104a to the client-side relay Web server 102 via the connection 105a. The relay web server 102 selects one of a plurality of other web servers on the CORBA AP server side capable of relaying communication to the CORBA AP server 104a, and connects to the other web server, here 103a, via the connection 106a. The request is sent, and the request is given from another Web server 103a to the CORBA AP server 104a.

【0010】

When the processing on the CORBA AP server 104a side is completed, the result is given to PC101 as a response via the other Web server 103a, connection 106a, relay Web server 102, and connection 105a, and after the response is completed, the connection between the servers is established. Be disconnected.

【0011】

After that, when the request for the second stage communication connection and processing is given to the relay Web server 102 from the PC 101 via the connection 105b in the session on the client side, the relay Web server 102 again sends the request to the CORBA AP server 104a. Select one of a plurality of other Web servers capable of relaying communication, that is, 103a to 103n, select the other Web server 103n here, give the request via the connection 106b, and make the request from the other Web server 103n. Given to the CORBA AP server 104a.

【0012】

In this way, in the communication within one session between the relay Web server 102 and the CORBA AP server 104a, the other Web that relays with the connection according to the state of the network at that time, that is, the number of established connections, etc. The server is selected and communication is distributed. The response as a processing result of the CORBA AP server 104a to the request is given to the PC101 via the other Web server 103n, the connection 106b, the relay Web server 102, and the connection 105b, and the CORBA AP server 104a also returns the response. It is necessary to distribute the communication to one of multiple other Web servers each time.

【0013】

In this way, in the conventional CORBA communication method using HTTP tunneling, the connection between the relay Web server and the other Web server in the previous stage of the CORBA AP server is disconnected after the response to the request from the client is completed, so that they are the same. Even if the communication is from the client within the same session, it is not possible to relay and communicate with the same other Web server, it takes time to establish a connection each time, and the CORBA AP server also responds. There is a problem that the response performance deteriorates because it is necessary to distribute the communication in order to return.

【0014】

In view of the above-mentioned problems, the subject of the present invention is the response performance of CORBA communication by HTTP tunneling by executing the communication corresponding to the communication connection request from the client in one session via the same other Web server. Is to improve.

【0015】

[Means for solving problems]

FIG. 1 is a basic functional block diagram of the communication distribution control method of the present invention. The figure shows a series of communications from a client, for example, multiple relay devices capable of relaying one communication in response to a connection request for one communication in a series of communications required within one session. It is a functional block diagram of the communication distribution control method which distributes to either.

【0016】

In the communication distribution control method of the present invention, in 1 the communication connection request from the client is received, and in 2 the communication connection corresponding to the above-mentioned series of communication is made by the identifier described in the communication connection request, for example, the session identifier. When it is determined whether or not it is set and a communication connection is set, the method of connecting the requested communication to a specific relay device as a relay destination of the set communication connection in 3 is used.

【0017】

Further, as the communication distribution control method of the present invention, a connection request for the first communication in the above-mentioned series of communications is received from the client, a communication connection for the communication for which the connection is requested is established, and the established connection is relayed. A method of connecting the requested communication to a specific relay device as a destination is also used.

【0018】

At this time, in the embodiment of the invention, the identifier corresponding to the established connection can be notified to the client side as an identifier to be described in the connection request of the communication after the first communication. The elapsed time since the first communication in a series of communications from the client was disconnected is monitored, and when the elapsed time exceeds a predetermined value, the communication connection corresponding to the series of communications and the communication connection thereof. It is also possible to invalidate the identifier corresponding to.

【0019】

In the communication distribution control device of the present invention, whether or not a communication connection corresponding to a series of communications is set by the connection request receiving means for receiving the communication connection request from the client and the identifier described in the communication connection request. It is provided with a connection determining means for determining the above, and a communication connecting means for connecting the communication requested to a specific relay device as a relay destination of the set communication connection when the communication connection is set.

【0020】

Further, the communication distribution control device of the present invention is a connection request receiving means for receiving a connection request for the first communication in a series of communications from a client, and a connection establishing means for establishing a communication connection corresponding to the communication requested to be connected. And a communication connection means for connecting the requested communication to a specific relay device as a relay destination of the established connection.

【0021】

Next, as a storage medium used by a computer for performing communication distribution in the present invention, a communication connection corresponding to a series of communications is performed by a step of receiving a connection request from a client and an identifier described in the communication connection request. A computer that determines whether or not is set, and when the communication connection is set, a step of connecting the requested communication to a specific relay device as a relay destination of the set communication connection. A computer-readable portable storage medium that stores the program to be executed by the client is used.

【0022】

Further, as a storage medium used by a computer for performing communication distribution, a step of receiving a connection request for the first communication in a series of communication on the client side and a step of establishing a communication connection for the communication requested to be connected. , A computer-readable portable storage medium that stores a program that causes the computer to execute the step of connecting the requested communication to a specific relay device as the relay destination of the established communication connection is used.

【0023】

In an embodiment of the invention, the program may further comprise a step of notifying the client of the identifier corresponding to the established communication connection as an identifier to be described in the connection request of the subsequent communication after the first communication. A step to monitor the elapsed time since the first communication in a series of communications from the client was disconnected, and when the elapsed time exceeds a predetermined value, the series of communications is supported. Further, a step of invalidating the communication connection and the identifier corresponding to the connection can be provided.

【0024】

As described above, according to the present invention, the communication connection is established in the first communication in the series of communications performed in one session, and the communication connection basically completes the series of communications in the session. It will be maintained until then.

【0025】

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 2 is a basic configuration block diagram of a communication system in which the communication distribution control method of the present invention is used. In the figure, the client-side personal computer (PC) 11 is used to execute the client-side session among a plurality of CORBA application (AP) servers that execute specific processes via the client-side relay Web server 12. Suppose you request one CORBA AP server, for example 14a, to do the necessary processing.

【0026】

However, for PC11 on the client side, it does not matter which of the multiple CORBA AP servers executes the requested processing, and on the client side, the processing is executed by the CORBA AP server 14a. Suppose you do not know.

【0027】

As mentioned above, the processing for the proxy executed by the client-side PC11 can be effectively executed by directly connecting the PC11 and the CORBA AP server 14a by a transmission line using the IIOP protocol. For example, when using the Internet, communication using the IIOP protocol is performed within the Internet because there are generally multiple relay servers such as proxy servers and gateways between PC11 and CORBA AP server 14a, and there is also a firewall. Generally, this is not possible, and it is necessary to convert the protocol to the HTTP protocol for communication within the Internet.

【0028】

Therefore, a request corresponding to one communication in the session as a series of communications from the client-side PC 11 is given to the client-side relay Web server 12 via the connection 15a, and the CORBA AP is given via the connection 16. It is given to the CORBA AP server 14a by one other web server 13a on the server side.

【0029】

The execution result of the process for this request is given to the PC 11 as a response from the CORBA AP server 14a via the other Web server 13a, the connection 16, the relay Web server 12, and the connection 15a.

【0030】

When a request for the next communication in one session is given from the PC 11 to the relay Web server 12 via the connection 15b, the request is given to the CORBA AP server 14a via the connection 16 and the other Web server 13a. And the processing result is given to PC11 by the reverse route.

【0031】

As described above, the communication connection between the client-side PC 11 and the relay Web server 12 is disconnected when a response corresponding to one request is obtained in the session, and the connection 15a is used for the request and the response. Is used, whereas connection 15b is used for requests and responses.

【0032】

On the other hand, in the present invention, the connection 16 between the relay Web server 12 and the other Web server 13a is maintained even after the response ends, for example, without being disconnected for a certain period of time, and the next request is made. If done in time, communication for the request and response will also be performed via the same connection 16, and communication between the relay web server 12 and the CORBA AP server 14a will always be through the other web server 13a. Will be executed.

【0033】

In the same manner, the request and response, and the communication corresponding to the request and response are executed between the relay Web server 12 and the CORBA AP server 14a via the connection 16 and the other Web server 13a.

【0034】

FIG. 3 is an explanatory diagram of a communication method using tunneling between the client side and the CORBA AP server in the present embodiment. Tunneling uses the Internet to transfer data from one network via another network, encapsulating frames generated by the source node with additional headers, and routing the contents of the additional headers. The transferred data used as information and encapsulated is transferred via the intermediate network.

【0035】

In FIG. 3, the processing request A from the PC 21 on the client side is transferred to the AP server 23 side via the tunnel server 22. The client-side PC21 consists of a client application (AP) 24 and a client object director (OD) 25 that converts the processing request protocol from IIOP to HTTP on the client side, and request A from the client side becomes the HTTP protocol. It is converted and given to the tunnel server 22.

【0036】

The tunnel server 22 is generally composed of a plurality of proxies (servers) 26 and a plurality of gateways 27, and a request A from the client side is given from one proxy 26 to one gateway 27, and HTTP is given by the gateway 27. The protocol conversion from to IIOP is performed and given to one CORBA AP server 28 that performs the processing corresponding to request A.

【0037】

FIG. 4 is a block diagram of a configuration example of a communication system corresponding to a plurality of clients in the present embodiment. In the figure, it is assumed that one session is executed by the personal computers PC-A31a and PC-B31b corresponding to the two clients, respectively.

【0038】

In FIG. 4, the communication between the PC-A31a and the CORBA AP server (not shown), that is, the CORBA AP server that executes the processing corresponding to the session executed by the PC-A31a, corresponds to the relay Web server 12 in FIG. It is executed via the proxy 32a and the gateway 33a corresponding to the other Web server 13a.

【0039】

The communication connection between PC-A31a and proxy 32a is disconnected after each response corresponding to one request, but the communication connection between proxy 32a and gateway 33a is basically between one session. Connection 34a is always used without being disconnected.

【0040】

Similarly, communication between the PC-B31b and the CORBA AP server that performs the processing corresponding to the session executed by it is executed via the proxy 32b and the gateway 33n. Communication between proxy 32b and gateway 33n is basically maintained for one session and is carried out through one connection 34b.

【0041】

FIG. 5 is a processing flowchart of the communication management method in the present embodiment. FIG. 6 is a flowchart of processing executed by the proxy 32a of FIG. 4, for example, and is a flowchart of processing performed in response to a request from a session on the client side, that is, a communication connection (and processing) request.

【0042】

When the process is started in FIG. 5, it is first determined in step S1 whether or not the session ID (identifier) as the session identifier is described in the request from the client side. This session ID is for identifying one session corresponding to a series of communications from the client side, and as a value thereof, for example, the IP address of the client is used or a communication connection request is made, as will be described later. The value is described inside the URL information in or inside the header information. If it is determined in step S1 that the session ID is not described in the request from the client side, the communication connection request starts a series of communication corresponding to one session in step S2. A new session ID is set in S2 corresponding to that session, a new connection 34a is established between the proxy 32a and, for example, the gateway 33a in step S3, and communication is performed with the gateway in step S4. , In the response that returns the processing result from the CORBA AP server to the client side in step S5, the session ID newly set in step S2 is notified, and the processing ends.

【0043】

If the session ID is already described in the request from the client side in step S1, it corresponds to the session ID already set in step S6 and stored in the memory (table) in the proxy 32a, for example. After the gateway connection is searched and gateway communication is performed in step S4, a new session ID is not set here, so step S5 only returns a response and ends the process.

【0044】

That is, in FIG. 5, when the communication connection request is the first request, for example, the request from PC-A31a in FIG. 4, the processes of steps S2 and S3 are executed, and in step S5, the session ID is the PC in the response. -Although it is notified to A31a, the processing of step S6 is executed for the next communication connection request, that is, the request, and the processing of session ID notification in step S5 is not executed.

【0045】

However, when the client's IP address is used as the session ID, the IP address naturally always exists in the communication connection request, so that the session ID is described in step S1 even for the first communication connection request. It is determined, and instead of searching for the connection that has already been set in step S6, a new connection is established, communication is performed with the gateway in step S4, and the session ID notification processing in step S5 is performed. It will not be executed.

【0046】

FIG. 6 is a processing flowchart of the communication connection management method in the present embodiment. In Fig. 5, when a new communication connection is established with the gateway in response to the first communication connection request in one section and the session ID is set, the contents are stored in a memory (table) (not shown). However, a timer (not shown) is started at the same time, and the elapsed time of the timer is monitored.

【0047】

That is, in step S11 of FIG. 6, it is determined by, for example, proxy 32a whether or not there is an access, that is, the next communication connection request in one session within a certain time after the timer is started, and if so, in step S11. Processing continues.

【0048】

On the other hand, if there is no access within a certain period of time, the session ID set in step S12 is invalidated, the established communication connection is released, and the process ends. Note that this fixed time can be, for example, 30 minutes as the duration of one session, which is the de facto standard in the Internet industry.

【0049】

FIG. 7 is an explanatory diagram of a communication method performed between the client-side PC-A31a and the proxy (server) 32a of FIG. 4, for example. In the figure, when the first communication connection request from the client side corresponding to the request in Fig. 4, that is, login as a connection establishment request is made, the proxy 32a sets the result of processing by the CORBA AP server corresponding to the response. A response with the ID added is returned, and in the second and subsequent communication connection requests from the client side, that is, the request in FIG. 4, and in, the session ID is given to the proxy 32a in addition to the connection processing request from the client side. , Each request will be returned.

【0050】

In the present embodiment, as described above, the method of determining the request corresponding to one session executed by a certain client, for example, the communication connection request ~ made from PC-A31a in FIG. 4 is a request corresponding to the same session. There are three methods to determine the method: using the client's IP address as the session identifier, including the session information in the URL information, and including the session identifier in the header information. Used.

【0051】

FIG. 8 is an explanatory diagram of a communication connection method when the IP address of the client is used as the session identifier. In the figure, the IIOP protocol communication connection (and processing) request from the client side, for example, the client AP in FIG. 3, is converted to the HTTP protocol by the client OD, and the converted communication connection request contains the URL, header, and body. It is output to the proxy side in the including format.

【0052】

On the proxy (server) side, in the table of its contents, for example, A, B and C as the IP addresses of the client side are already requested for the three sessions S1, S2, and S3, and the connection is also requested by the client. It stores that a connection and is established as a communication connection for transmitting communication to the gateway side.

【0053】

If the IP address of the client currently requesting a connection is, for example, "B", the connection is selected as the connection to the gateway side, a communication connection request is sent to the gateway as the destination of this connection, and the gateway. The HTTP to IIOP protocol conversion is performed by, and the request converted to IIOP is transmitted to the CORBA AP server.

【0054】

In FIG. 8, if the IP address described in the communication connection request sent from the client side to the proxy is not stored in the table in the proxy, the IP address and its IP address are used for a new session such as S4. A connection for transmitting proxy communication, for example, a connection is set, and a communication connection request is sent to the gateway of the connection destination.

【0055】

When an IP address is used as this session identifier, the same connection is used for the same client even if the sessions are different. That is, the communication connection request from the client whose IP address is "B" is always made using the connection. Therefore, the gateway of the other party of the connection is always the same, and even if the CORBA AP server that performs the processing required to execute the two sessions is different, the proxy and the gateway always communicate using the same connection. Will be done.

【0056】

FIG. 9 is an explanatory diagram of a communication method when a session identifier is included in the header information. In the figure, as the first communication connection request from the client side, a request consisting of a URL, a header, and a body is sent to the proxy side in the same manner as in FIG.

【0057】

Similar to the case in FIG. 8, inside the proxy, for example, the session identifier to be added to the header information corresponding to the session numbers S1 to S3, for example, the AAA corresponding to the session number S1 and the communication corresponding to the session are transmitted. The number of the communication connection with the gateway for this is stored.

【0058】

These already stored session identifiers and connection numbers are session identifiers and connection numbers corresponding to those for which communication within the session has already been started in the past.

【0059】

On the other hand, if the request sent from the client side is the first communication connection request, the session identifier is not yet included in the header information, and the proxy side responds to the first connection request. For example, S4 as the session number, ZZZ as the session identifier, and the corresponding communication connection are stored in the table, a communication connection request is given to the gateway via the communication connection, and then protocol conversion is performed as in FIG. The connection (and processing) request data is given to the CORBA AP server.

【0060】

FIG. 10 is an example of header information in the first communication connection request described in FIG. In this header information, A and B indicate the work executed by the corresponding session, and C indicates the argument. In this header information, no data is described between B and C, and the fact that no data is described here indicates that this is the first communication connection request.

【0061】

As described in FIG. 9, the session number S4 and the session ID ZZZ are set by the proxy side in response to this communication connection request. This set new session ID is added to the header information in the response to PC-A31a in FIG. 4, for example, and is returned from the proxy 32a to the client side.

【0062】

At this time, ZZZ as a session ID is added between B and C in the header information of FIG. As an additional method for this session ID, for example, a method in which the data additionally described in the HTTP header can be recognized and stored on the browser side, for example, a netscape cookie (Cookie) is used.

【0063】

By returning the response including the header information to which the session ID is added from the proxy side to the PC side in this way, the header information including the session ID is used for the header information in the second and subsequent communication connection requests. It becomes possible.

【0064】

FIG. 11 is an explanatory diagram of a communication method when adding a session ID to a URL. The method in this figure is almost the same as in FIG. 9, except that the session ID is added to the URL, not in the header information. As in FIG. 9, in the first communication connection request, the session ID is not included in the URL, and it corresponds to the session ID newly set by the proxy, for example Z, via the established communication connection. A communication connection request is sent to the gateway, and the set session ID Z is added to the URL of the response to the request and sent to the client side. This set session ID, for example Z, is added to the URL of the second and subsequent communication connection requests and sent to the proxy.

【0065】

Each communication device in the communication system as described above, for example, the relay Web server 12 in FIG. 2, the proxy 32a in FIG. 4, and the like can be realized by a general computer system. FIG. 12 shows a configuration example of such a computer system. In the figure, the computer 51 is composed of a main body 52 and a memory 53.

【0066】

The memory 53 is a storage device such as a random access memory (RAM), a hard disk, or a magnetic disk, and such a memory 53 can be used in, for example, the above-mentioned flowcharts of FIGS. The communication distribution control in the present invention is realized by storing the programs described in ~ 10 and the like and executing the programs by the main body 52.

【0067】

Such a program is sent from the program provider side via the network 54, loaded into the computer 51, and stored in a commercially available and distributed portable storage medium 55, and the program is stored in the computer. It can also be executed by being loaded on 51.

【0068】

As the portable storage medium 55, various types of storage media such as CD-ROMs, floppy (registered trademark) disks, optical disks, and magneto-optical disks can be used, and the above-mentioned programs are stored in such storage media. The communication distribution control in the present invention is also possible by setting the portable storage medium 55 in the computer 51.

【0069】

In the above description, an embodiment of the invention has been described centering on an HTTP tunneling method in which a client requests a CORBA AP server for processing necessary for executing a session via the Internet. It goes without saying that it can be used for various communication methods within the scope of claims without being limited to the above embodiments.

【0070】

[Effect of the invention]

As described above, according to the present invention, it is possible to use the same other Web server for one session as a relay Web server to the CORBA AP server, and it is possible to request a communication connection within one session. , It is not necessary to establish a communication connection, and the response performance for receiving the response from the CORBA AP server is improved, which greatly contributes to the efficiency improvement of CORBA communication by HTTP tunneling.

[Simple explanation of drawings]

[Figure 1]

It is a functional block diagram of the communication distribution control method of this invention.

[Figure 2]

It is a basic block diagram of the communication system which uses the communication distribution control system of this invention.

[Fig. 3]

It is explanatory drawing of the communication method using tunneling between a client side and a CORBA AP server.

[Fig. 4]

It is a block diagram of the configuration example of the communication system corresponding to a plurality of clients.

[Fig. 5]

It is a processing flowchart of the communication management method in this embodiment.

[Fig. 6]

It is a processing flowchart of a communication connection management method.

[Fig. 7]

It is explanatory drawing of the communication method between a personal computer on a client side and a proxy server.

[Fig. 8]

It is explanatory drawing of the communication system in the case of using an IP address as a session ID.

[Fig. 9]

It is explanatory drawing of the communication method when the session ID is included in the header information.

[Fig. 10]

It is a figure which shows the example of the header information.

[Fig. 11]

It is explanatory drawing of the communication method when the session ID is included in the URL.

[Fig. 12]

It is a figure explaining the loading of the program for realizing this invention into a computer.

[Fig. 13]

It is explanatory drawing of the conventional example of the CORBA communication system by HTTP tunneling.

[Explanation of symbols]

11 Personal computer (PC) 12 Relay web server 13a Other Web server 14a CORBA AP server 15a, ..., 16 communication connections 24 Client AP 25 Client OD 26 Proxy 27 gateway 28 CORBA AP server