JP2008236543A - Communication path control method and program, and communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain load distribution on a network without restricting services that computer enjoy, in the environment where a plurality of communication paths exist between the computers which communicate with each other via the network. <P>SOLUTION: When a connection is requested from an application 13, 23, a path control section 15, 25 negotiates with the path control section 25, 15 of an opposite computer and selects a communication path. Both the path control sections 15, 25 then perform communication using not an address that the application 13, 23 is conscious of, but an address with which communication can be performed on the selected communication path. When delivering data to the application 13, 23, the address that the application 13, 23 is conscious of is reported. Furthermore, each time a connection is requested from the application 13, 23, path selection processing is performed to separate a communication path for each connection. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a communication path control technique.

In a system in which computers communicate with each other via a network via TCP / IP (Transmission Control Protocol / Internet Protocol), in order to secure a detour route in the event of a network load distribution or failure, the computer must communicate with the other party's IP A technique for selecting a communication processing device (router or the like) to be used for communication with the communication partner for each address has been proposed (see Patent Document 1).
JP 2003-348134 A

  However, the prior art described above has the following problems. For example, when a plurality of communication processing devices are used, the source IP address varies depending on the communication processing device selected by the own computer when establishing a connection. For this reason, when the content of the service provided by the communication partner computer for each source IP address is restricted, there is a problem that the service received by the own computer is also restricted.

  Further, even if the IP addresses of the communication processing devices are the same, a router installed between the communication processing device and the communication partner computer normally has only one communication path for one destination IP address. I can't hold it. For this reason, even if communication (outbound route) from the own computer side can be distributed to a plurality of computers, communication (return route) from the communication partner computer side is biased to one route. That is, there is a problem that load distribution cannot be realized for the return path. Further, when the communication path is different between the forward path and the return path in this way, a packet from the communication partner computer side may be blocked as an illegal packet in a firewall or the like installed on the network.

  The present invention solves the above-described problem and realizes load distribution on a network without restricting the services received by the computer in an environment in which a plurality of communication paths exist between computers communicating via a network. It aims to provide a means.

  In order to solve the above-described problem, in the present invention, a first communication device (computer) and a second communication device (computer) negotiate with each other to establish a connection. In data communication, the connection information (application connection information) recognized by the application of each communication device is associated with the connection information (communication connection information) used by the path control unit for actual communication. Create route management information. In each communication device, the created route management information is stored in the storage unit. After that, when there is a data communication request from the application in each communication device, the route control unit does not specify the connection requested by the application, but the communication connection corresponding to this connection in this route management information. Data communication. Then, the path control unit notifies the application that data communication has been performed through the connection requested by the application. In this way, for example, when a plurality of addresses (IP addresses) are assigned to a communication device and the communication device is a source and receives a service from another communication device, the application of the other communication device Can be recognized as the same IP address if they are the same communication device, so that services that can be received by the communication device that is the transmission source are not restricted.

  In addition, the first communication device may establish data connection and establish data communication with the second communication device. In such a case, the second communication device also holds a plurality of connection information as a route addressed to the first communication device in the route management information, and performs data communication based on the route management information. As a result, the communication path does not differ between the forward path and the return path, and network load distribution can be realized.

  According to the present invention, in an environment where a plurality of communication paths exist between computers that communicate via a network, the services received by the computers are not limited, and network load distribution can be realized.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of a communication path control system according to the present embodiment. The configuration of the communication path control system according to the present embodiment will be described with reference to FIG.

  Here, a case where a plurality of paths (communication paths) 31 and 41 are used in data communication between the computer 10 (first communication apparatus) and the computer 20 (second communication apparatus) will be described as an example. To do. Of these, the route 31 is a route passing through the network 30, and the route 41 is a route passing through the network 40.

<Computer 10>
The computer 10 includes a CPU (Central Processing Unit) 11, a memory (storage unit) 12, and network adapters (interface units) 16 and 17. Although not shown, the computer 10 includes a disk device, a flash device, etc. (hereinafter referred to as “disk device etc.”) for storing various programs and data. The CPU 11 loads a program stored in a disk device or the like onto the memory 12 and performs various arithmetic processes for the computer 10 to perform communication. The memory 12 is, for example, a RAM (Random Access Memory) such as a semiconductor memory, and is a storage medium used when the CPU 11 performs arithmetic processing. The network adapters 16 and 17 are network interfaces for the computer 10 to communicate via the networks 30 and 40.

  Note that the memory 12 includes, in a predetermined area, an application 13 used for communication, an OS (Operating System) 14 of the computer 10, a path control unit 15, a path management table (path management information) 151, a path information list (path) Information) 152 and the like.

  The path control unit 15 establishes a connection with another computer (for example, the computer 20), or performs path control when the computer 10 performs communication via the networks 30 and 40.

  The route management table 151 shows connection information established by the computer 10. The route management table 151 is information indicating a connection used by the route control unit 15 for each connection that the application 13 is aware of. That is, the connection information for application and the connection information for communication corresponding to this connection are shown. The route management table 151 is referred to when the route control unit 15 performs data communication. Details of the route management table 151 will be described later with reference to FIG.

  The route information list 152 indicates a communication route for performing communication with a node (computer) of the IP address for each destination IP address. The route information list 152 is created, for example, when the route control unit 15 exchanges IP addresses with other computers (for example, the computer 20). Communication paths registered in the path information list 152 include communication paths for which no connection has been established. The route information list 152 is referred to when the route control unit 15 selects a communication route and creates the route management table 151. Details of the route information list 152 will be described later with reference to FIG.

  The function of the path control unit 15 is realized by the CPU 11 executing a communication path control program stored in a disk device or the like. That is, in FIG. 1, the path control unit 15 is depicted as a state in which a program stored in a disk device or the like is loaded on the memory 12.

  In the following description, the IP address “10.0.0.1” is set for the network adapter 16, and the IP address “10.1.0.1” is set for the network adapter 17. A case will be described as an example.

<Computer 20>
Further, like the computer 10, the computer 20 also includes a CPU 21, a memory (second storage unit) 22, and network adapters (second interface units) 26 and 27. Although not shown, the computer 20 includes a disk device that stores various programs and data. This memory 22 has, in a predetermined area, an application 23 used for communication, an OS 24 of the computer 20, a path control unit (second path control unit) 25, a path management table (second path management information) 251, A route information list 252 and the like are provided.

  The path control unit 25 performs path control when the computer 20 performs communication via the networks 30 and 40.

  The path management table 251 is information indicating a connection actually used for each connection that the application 23 is aware of. That is, similar to the route management table 151, application connection information and communication connection information corresponding to this connection are shown. The route management table 251 is also referred to when the route control unit 25 performs data communication based on a request from the application 23. Details of the route management table 251 will be described later with reference to FIG.

  Similarly to the route information list 152 described above, the route information list 252 also shows a communication route for performing communication with a node (computer) of the IP address for each destination IP address. The route information list 252 is also created, for example, by the route control unit 25 exchanging mutual IP addresses with another computer (for example, the computer 10). The communication path registered in the path information list 252 includes a communication path for which no connection has been established. The route information list 252 is referred to when the route control unit 25 selects a communication route and creates the route management table 251. Details of the route information list 252 will be described later with reference to FIG.

  Further, the case where the IP address “10.0.0.2” is set in the network adapter 26 and the IP address “10.1.0.2” is set in the network adapter 27 will be described as an example. To do.

  The programs for realizing the functions of the applications 13 and 23, the OS 14 and 24, and the path control units 15 and 25 are installed in the computers 10 and 20 via a storage medium such as a CD-ROM or a network, for example. Shall be.

<Description of operation>
Next, referring to FIG. 1 and using FIG. 2, a TCP (Transmission Control Protocol) connection established between the application 13 of the computer 10 and the application 23 of the computer 20 (hereinafter simply referred to as a connection). Will be described. First, a case where one connection is established between the computers 10 and 20 will be described. FIG. 2 is a sequence diagram showing operations of the computers 10 and 20 of FIG.

  Here, a case where the computer 10 in FIG. 1 operates as a client and the computer 20 operates as a server will be described as an example. An example will be described in which the application 13 of the computer 10 uses “10.1.0.1” as its own IP address, and the computer 20 opens the port “10002”. It is assumed that no information has been set in the route management tables 151 and 251 and the route information lists 152 and 252 before the connection is established.

  First, the path control unit 25 of the computer 20 in FIG. 1 opens a port “50000” for path control connection with the path control unit 15 of the computer 10 (S515). Next, the path control unit 25 receives a port open request for the port “10002” from the application 23 (S516), and opens the port “10002”. Then, the computer 20 waits for a connection establishment request from the computer 10.

  Next, the path control unit 15 of the computer 10 connects from the application 13 with the own IP address “10.0.1. 1”, the other party IP address “10.0.0.2”, and the other party port “10002”. When the establishment request is received (S500), the route information list 152 is searched, and whether or not the route information list 152 has route information (communication route information) regarding the partner (destination) IP address “10.0.0.2”. Is determined (S501).

  In S501, when there is no route information regarding the destination IP address “10.0.0.2” in the route information list 152 of the computer 10 (“None” in S501), the route control unit 15 displays the route control unit of the computer 20. 25, an attempt is made to establish a path control connection (connection) for acquiring path information regarding the IP address “10.0.0.2” and port “50000” of the computer 20 (S502, S517).

  On the other hand, if the route information list 152 of the computer 10 includes route information regarding the destination IP address “10.0.0.2” (“Yes” in S501), the process proceeds to S507. This S507 will be described later.

  In S502, when the path control unit 15 of the computer 10 fails to establish a path control connection with the computer 20 ("failed" in S503), the path control unit 15 connects the partner computer (computer 20) to The computer is determined not to be compatible with the system of the present embodiment, and a normal connection is established based on the prior art (S514).

  On the other hand, when the route control unit 15 of the computer 10 has successfully established a route control connection with the computer 20 (“success” in S503), route information (communication route information) is exchanged with the route control unit 25 of the computer 20. Exchange (S504, S518).

  For example, the path control unit 15 of the computer 10 uses the IP address held by the computer 10 (the IP address “10.0 assigned to the network adapters 16 and 17 in FIG. 1) on the path control connection established in S502 and S507. .0.1 ”and“ 10.1.0.1 ”) to the path control unit 25 of the computer 20. The route control unit 25 of the computer 20 also has an IP address held by the computer 20 (IP addresses “10.0.0.2” and “10.1.0.2” assigned to the network adapters 26 and 27). Is notified to the route control unit 15 of the computer 10.

  Thereby, the route control unit 15 of the computer 10 acquires the IP address held by the computer 20, and the route control unit 25 of the computer 20 also acquires the IP address held by the computer 10.

  After S504 and S518 described above, the route control units 15 and 25 create route information lists 152 and 252 based on the route information exchanged in S504 and S518 (S505 and S519). The created route management tables 151 and 252 are stored in the memories 12 and 22. Then, the route control units 15 and 25 confirm the respective route states by PING or the like (S506, S520), and write the confirmed results (route state information) in the route information lists 152 and 252.

  That is, for each destination computer, the route control units 15 and 25 store, in the route information lists 152 and 252, communication routes that can be considered from combinations of the IP address assigned to the destination computer and the IP address assigned to the own computer. Write. Then, the route control units 15 and 25 confirm the route state for each of the communication routes and write them in the route information lists 152 and 252. The route information lists 152 and 252 created here will be described with reference to FIGS.

  3A is a diagram illustrating the route information list 152 after S506 in FIG. 2, and FIG. 3B is a diagram illustrating the route information list 252 after S520 in FIG. (C) will be described later.

  As illustrated in FIG. 3A, the route information list 152 includes the communication route information acquired in S504 as information corresponding to the destination IP address 605 (the IP address “10.0.0.2” of the computer 20). (A combination of the IP address 606 of the partner computer and the IP address 607 of the own computer) and the status information 608 of each communication path acquired in S506 are stored. For example, the communication path information indicated by reference numeral 601 is the communication path to the destination IP address “10.0.0.2”, the IP address of the partner computer is “10.0.0.2”, and the IP address of the own computer Indicates that there is a communication path “10.0.0.1”, and this communication path is in a state where communication can be performed normally.

  As illustrated in FIG. 3B, the path information list 252 includes the communication path information acquired in S518 as information corresponding to the destination IP address 615 (the IP address “10.1.0.1” of the computer 10). (A combination of the IP address 616 of the partner computer and the IP address 617 of the own computer) and the status information 618 of each communication path acquired in S520 are stored.

  Returning to the description of FIG. When the route control units 15 and 25 create the route information lists 152 and 252 as described above, the communication route registered as a communicable state is selected from the communication route information indicated in the route information lists 152 and 252. (S507). In selecting the communication path here, first, a communication path that is communicable in the path information lists 152 and 252 is selected, and the selected communication path is selected by round robin or the like.

  For example, the route control unit 15 selects the communication route indicated by reference numerals 601 and 604 in the route information list 152 illustrated in FIG. 3A, and selects the communication route indicated by reference numeral 601 by round robin or the like. select.

  Next, the path control unit 15 determines the selection result of S507, and when there is no communicable path (communication path) (“No” in S508 in FIG. 2), notifies the application 13 of a connection establishment failure (S509). ).

  On the other hand, when there is a communicable communication path (“Yes” in S508), the path control unit 15 negotiates with the path control unit 25 of the computer 20 over the path control connection, and communicates with the communication path selected in S507. The communication path for performing the above is set (S510, S521). For example, communication path setting for performing communication through the communication path indicated by reference numeral 601 in the path information list 152 illustrated in FIG.

  Details of the communication path setting process here will be described with reference to FIG. FIG. 4 is a sequence diagram showing the communication path setting process of S510 and S521 of FIG.

  The path control unit 15 of the computer 10 transmits a setting request (communication path setting request) including connection information used for the communication path and application connection information to the path control unit 25 of the computer 20 (S800). That is, the path control unit 15 uses the connection information requested by the application 13 to establish in S500 and the connection using the IP address that can be communicated through the communication path selected in S507 (the communication path indicated by reference numeral 601 in FIG. 3A). Information (for example, the partner IP address “10.0.0.2”, the host IP address “10.0.0.1”, the partner port “10002”, the host port “10001”) is set as a setting request to the computer 20. Transmit to the route control unit 25. Upon receiving this setting request (S801), the path control unit 25 of the computer 20 determines whether or not this communication path can be set based on the information in the path information list 252 (see FIG. 3B) (S802). ).

  For example, the path control unit 25 determines whether or not the state of the communication path selected in S507 is “normal” in the path information list 252 of its own computer 20. Here, when the path control unit 25 permits setting of the communication path (“permitted” in S802), the connection information requested by the application 13 to establish in S500 and the connection information of the communication path selected in S507 are respectively used for communication. Connection information and application connection information are added to the route management table 251 (S803). Then, the path control unit 25 transmits the determination result of S802 to the path control unit 15 of the computer 10 as a setting response (communication path setting response) (S805).

  Here, the path management table 251 after the execution of S803 will be described with reference to FIG. FIG. 5B illustrates the path management table 251 after the execution of S803 in FIG. As shown in FIG. 5B, the path management table 251 includes application connection information (connection information recognized by the application 23) 723 and a communication connection corresponding to the application connection information 723. Information (connection information used for communication by the path control unit 25 in this application connection) 722 is registered. Here, as the connection information 723 for the application, the partner IP address “10.1.0.1”, the partner port number “10001”, the own IP address “10.0.0.2”, the own port number “10002”. Connection information is registered. As communication connection information 722 corresponding to the application connection information 723, the partner IP address “10.0.0.1”, the partner port number “10001”, and the own IP address “10.0.0. 2 ”and connection information“ self port number “10002” are registered.

  The path control unit 25 can determine which connection should be actually used when a connection request is received from the application 23 by referring to such a path management table 251.

  Returning to the description of FIG. In S802 of FIG. 4, when the communication path indicated in the connection information of the setting request received in S801 is registered as “failure” in the path information list 252, the path control unit 25 does not permit the setting of the communication path ( (Rejected ”in S802). Then, the route control unit 25 selects another communication route from the route information list 252 (S804). Then, the path control unit 25 transmits the selected other communication path and the determination result of S802 (communication path setting rejection) to the path control unit 15 of the computer 10 as a setting response (S805).

  When the path control unit 25 rejects the communication path setting in S802, in this example, it is not necessary to select another communication path in S804, and only the determination result of the communication path setting rejection may be transmitted in S805. Good.

  After S805, when receiving the communication path setting response from the computer 20 (S806), the path control unit 15 of the computer 10 determines the response result (determination result) included in the received setting response (S807). Here, when the determination result is “permitted”, the path control unit 15 adds the communication path information of the communication path permitted to set the communication path to the path management table 151 as in S803 ( S808).

  FIG. 5A illustrates the path management table 151 after the execution of S808 in FIG. As shown in FIG. 5A, the path management table 151 also includes connection information for application (connection information recognized by the application 13) 703 and communication connection information (path control unit) corresponding to this connection. 15, connection information 702 of connection used for communication) is registered. Here, as the connection information 703 for the application, the partner IP address “10.0.0.2”, the partner port number “10002”, the own IP address “10.1.0.1”, the own port number “10001”. Connection information is registered. Further, in such a connection, as the connection information 702 for communication, the partner IP address “10.0.0.2”, the partner port number “10002”, the own IP address “10.0.0.1”, the self A combination of port number “10001” is registered.

  The path control unit 15 can determine which connection should be used when a connection request is received from the application 13 by referring to such a path management table 151.

  Returning to the description of FIG. In S807, when the response result (determination result) of the setting response received by the route control unit 15 is “rejected” (“rejected” in S807), the route control unit 15 includes the communication route included in this setting response. Information is acquired (S809). That is, the communication path information of the communication path selected on the path control unit 25 side of the computer 20 is acquired. Then, the route control unit 15 determines whether or not the communication route selected on the route control unit 25 side can be adopted based on the route information list 152 and the like (S810). The determination as to whether or not the information can be adopted is, for example, whether or not the communication route information acquired in S809 is registered in the route information list 152, and if this communication route information is registered in the route information list 152, the route information The determination is made based on whether or not the state of the communication path shown in the list 152 is “normal”. Here, when the adoption of the communication route selected by the route control unit 25 is “reject” (“reject” in S810), or the communication route selected by the route control unit 25 in the communication route setting response received in S806. If the information is not included, the path control unit 15 determines that the communication path setting has failed (S811), and ends the process.

  On the other hand, in S810, when the route control unit 15 determines that the adoption of the communication route selected on the route control unit 25 side is “permitted” (“permitted” in S810), the process returns to S800, and the route control unit 15 A setting request regarding the communication path is transmitted to the path control unit 25 of the computer 20. And the process after S801 is performed.

  In this way, the path control unit 15 of the computer 10 and the path control unit 25 of the computer 20 perform communication path setting.

  Returning to the description of FIG. In S511 of FIG. 2, when the path control unit 15 fails to set the communication path (“failure” in S511), the connection establishment failure is notified to the application 13 (S509).

  On the other hand, when the path control unit 15 succeeds in setting the communication path in S510 (“success” in S511), the path control unit 15 registers the connection information for communication registered in the path management table 151 set in S510 (FIG. A connection is established based on the reference numeral 702 in FIG. 5 (a) (S512). Then, the path control unit 15 notifies the application 13 of successful connection establishment to the application 13 (S513).

  At this time, the connection information notified to the application 13 by the path control unit 15 corresponds to the connection information for communication, not the connection information for communication in the path management table 151 (see reference numeral 702 in FIG. 5A). Application connection information (see reference numeral 703 in FIG. 5A).

  Further, after receiving a connection establishment request from the route control unit 15 of the computer 10 after S521, the route control unit 25 of the computer 20 receives connection information for communication in the route management table 251 (see reference numeral 724 in FIG. 5B). ) To determine whether there is information that matches the connection establishment request (S522). Here, referring to the connection information for communication in the route management table 251, when there is information that matches the connection establishment request (“Yes” in S522), the received connection establishment request is notified to the application 23 (S523). Then, a connection is established with the path control unit 15 of the computer 10 (S524).

  Here, the connection establishment request notified by the route control unit 25 to the application 23 is not connection connection request received but connection information for application in the route management table 251 (see reference numeral 722 in FIG. 5B).

  For example, when the connection establishment request received by the route control unit 25 is the connection indicated by reference numeral 722 in FIG. 5B, the route control unit 25 notifies the application 23 of connection information for the application indicated by reference number 723. To do. That is, the path control unit 25 causes the application 23 to recognize that the connection establishment request indicated by reference numeral 723 has been received even when the connection establishment request indicated by reference numeral 722 is actually received.

  On the other hand, when there is no information matching the connection establishment request in the route management table 251 (“No” in S522), connection establishment processing is performed according to a normal procedure (S525).

  In this way, the computers 10 and 20 establish a connection.

  Thereafter, the route control unit 15 of the computer 10 performs the following processing with reference to the route management table 151 (see FIG. 5A). For example, the data requested by the application 13 to be transmitted through the connection indicated by reference numeral 703 in FIG. 5A is transmitted by the path control unit 15 to the computer 20 using the connection indicated by reference numeral 702. When the path control unit 15 receives data from the computer 20 using the connection indicated by reference numeral 702, the path control unit 15 notifies the application 13 as data of the connection indicated by reference numeral 703.

  The route control unit 25 of the computer 20 also performs the following processing with reference to the route management table 251 (see FIG. 5B). For example, the data requested by the application 23 to be transmitted through the connection indicated by reference numeral 723 in FIG. 5B is transmitted to the computer 10 by the path control unit 25 using the connection indicated by reference numeral 722. When the route control unit 25 receives data from the computer 10 using the connection indicated by reference numeral 722, the route control unit 25 notifies the application 23 as connection data indicated by reference numeral 723.

  That is, even when data is transmitted / received between the computer 10 and the computer 20 in FIG. 1 using any of the routes 31 and 41, the IP address “ Recognizing that data is being transmitted / received on the connection connecting “0.0.0.2” (IP address of network adapter 17) and IP address “10.1.0.1” (network adapter 26) Can do.

  When the connection is released, the route control units 15 and 25 delete the corresponding information from the route management tables 151 and 251.

  Further, when a path failure occurs after the connection is established in the computers 10 and 20, the following processing is performed.

  That is, first, the path control units 15 and 25 search for connection information of a path in which a path failure has occurred from communication connection information registered in the path management tables 151 and 251. Next, the partner IP address is obtained from the connection information for the application corresponding to the retrieved connection information. Then, using this partner IP address as the destination address, the route control unit 15 of the computer 10 executes the above-described S507 to S512, and the route control unit 25 of the computer 20 also executes the above-described S521 to S524 to control the route. The units 15 and 25 negotiate to establish a connection through another communication path. Then, the route control units 15 and 25 delete the connection information in which the route failure has occurred in the connection information for communication in the route management tables 151 and 251 and release the connection in which the route failure has occurred. Then, the connection information of the newly established connection is added to the route management tables 151 and 251.

  By doing so, it is possible to continue the communication by dynamically switching the communication path without making the application aware of the failure.

<When establishing multiple connections>
Next, the case where the computers 10 and 20 establish the second and subsequent connections will be described with reference to FIGS. Here, the case where the route control unit 15 has already created the route information list 152 and the route management table 151 and the route control unit 25 has already created the route information list 252 and the route management table 251 will be described. Further, it is assumed that the computers 10 and 20 have established connections indicated by reference numeral 701 in FIG. 5A and reference numeral 721 in FIG. 6A is a diagram illustrating a path management table 151 after the computer 10 of FIG. 1 has established the second connection (second connection), and FIG. 6B is a diagram of the computer 20 of FIG. It is the figure which illustrated the path | route management table 251 after establishing a 2nd connection (2nd connection).

  First, the procedure for establishing the second connection will be described with reference to FIG. The route control unit 15 of the computer 10 receives a connection establishment request from the application 13 with its own IP address “10.1.0.1”, destination IP address “10.0.0.2”, and partner port “10002”. (S500).

  Next, the route control unit 15 determines whether there is route information (communication route information) corresponding to the destination IP address “10.0.0.2” stored in the route information list 152 (S501). ). Here, when the route information list 152 includes route information related to the destination IP address “10.0.0.2” (“Yes” in S501), the corresponding communication route (reference numerals 601 to 604 in FIG. 3A). ) Is selected from available communication paths (S507). Here, as the communication path to be selected, for example, a communication path indicated by reference numeral 604 is selected by a method such as round robin, not the communication path indicated by reference numeral 601 selected when the first connection is established. On the other hand, when there is no corresponding route information (“None” in S501), the processing from S502 onward is executed.

  In S507, for example, when the communication path indicated by reference numeral 604 in FIG. 3A is selected, the path control unit 15 performs the same processing as in S508 to S511 and S521 described above. Then, the route control unit 15 creates a route management table 151 as illustrated in FIG. 6A, and the route control unit 25 creates a route management table 251 as illustrated in FIG. 6B.

  As illustrated in FIG. 6A, in the route management table 151, information related to the second connection (refer to reference numeral 708) is registered in addition to information related to the first connection (refer to reference numeral 701). The information relating to the second connection indicated by reference numeral 708 is created based on the communication path information indicated by reference numeral 604 in FIG. 3A, and includes connection information for communication 709 and connection information for application. 710.

  Similarly, in the route management table 251 of the route control unit 25, as illustrated in FIG. 6B, the route management table 251 includes the second connection in addition to information on the first connection (see reference numeral 721). Information regarding (see reference numeral 728) is registered. The information relating to the second connection indicated by reference numeral 728 is created based on the communication path information indicated by reference numeral 614 in FIG. Information relating to the second connection indicated by reference numeral 728 also includes connection information 729 for communication and connection information 730 for application.

  Next, when the path control units 15 and 25 establish connections indicated by reference numerals 709 and 729, respectively (S512 and S524 in FIG. 2), the applications 13 and 23 are instructed in FIGS. 6A and 6B. Notification is made that the connection establishment indicated by reference numerals 710 and 730 is successful (S513, S523).

  Then, after establishing such a connection, the path control units 15 and 25 perform data transmission / reception using the established connection in the same manner as in the above procedure.

  For example, the route control unit 15 performs the following processing according to information stored in the route management table 151 illustrated in FIG. In other words, when the application 13 makes a data transmission request using the connection indicated by reference numeral 703, the path control unit 15 transmits data to the computer 20 using the connection indicated by reference numeral 702. Then, the path control unit 15 notifies the application 13 that the data transmission is performed at the connection address indicated by reference numeral 703. In addition, the path control unit 15 notifies the address of the connection indicated by reference numeral 703 when passing the data received by the connection indicated by reference numeral 702 to the application 13. Further, when the application 13 makes a data transmission request using the connection indicated by reference numeral 710, the path control unit 15 transmits data to the computer 20 using the connection indicated by reference numeral 709. Then, the path control unit 15 notifies the application 13 that the data transmission is performed at the connection address indicated by reference numeral 710. Further, the path control unit 15 notifies the application 13 that the data received through the connection indicated by reference numeral 709 is received from the computer 20 using the connection address indicated by reference numeral 710. That is, the path control unit 15 causes the application 13 to recognize the data communication using the connection for communication as if the data communication was performed using the connection for the application with reference to the path management table 151.

  Similarly, the path control unit 25 refers to the path management table 251 for the application 23 for data communication using the communication connection of the path management table 251 illustrated in FIG. Then, it is recognized as if data communication was performed using the application connection.

  When the connection is released, the route control units 15 and 25 delete the corresponding information from the route management tables 151 and 251.

  Thus, even if the data transmission / reception communication path is different for each connection, such as the first connection is the path 31 in FIG. It is possible to recognize the connection between the address “10.1.0.1” and the IP address “10.0.0.2”.

  Thereafter, every time there is a connection establishment request from the application 13, the route control unit 15 selects a communication route from the route information list 152 in the same procedure as described above. Then, the path control unit 15 registers application connection information and communication connection information in the path management table 151 in association with each other. Then, the route control unit 15 performs connection establishment and data communication based on the information.

  In the above-described embodiment, the case where the connection from the application 13 side of the computer 10 to the application 23 of the computer 20 is established has been described. However, the path control unit 15 and the path control unit 25 have the same functions. The connection from the application 23 side to the application 13 may be established.

  Further, in FIG. 2, the route information exchange (S504, S518) and the communication route setting (S510, S521) between the route control units 15 and 25 have been described as an example using a route control connection. It is not limited to. For example, it may be implemented by UDP (User Datagram Protocol), broadcast, or the like. Furthermore, although the procedure for setting the route information lists 152 and 252 has been described with reference to FIG. 2, it may of course be set in advance.

  Further, the route information lists 152 and 252 are not limited to the contents of (a) and (b) of FIG. FIG. 3C is a diagram illustrating a route information list 600 that is another example of the route information list.

  For example, as shown in the route information list 600 of FIG. 3C, destination IP address information (IP address “10.1.0.1”) indicated by reference numeral 625 as the information of each communication route, and the destination IP address Communication path corresponding to the information, that is, the IP address information 626 (IP address “10.0.0.1”, “10.1.0.1”) of the partner computer and the IP address information 627 (IP address) of the own computer In addition to “10.0.0.2” and “10.1.0.2”) and the status 628 of each route, information such as response performance information 631 of the communication route may be stored.

  Further, the method of selecting a communication route (S507, S802, S804) is not limited to round robin, and can be used based on the information in the route information list 600 illustrated in FIG. It is also possible to select a communication route having the smallest value of the connection number information 629 from among possible routes. Alternatively, the communication route with the smallest communication load may be selected in the communication load information 630 of the route information list 600, or the communication route with the highest response performance may be selected in the response performance information 631.

  2, the route control unit 25 of the computer 20 creates the route information list 252. However, the route control unit 25 may not create the route information list 252. That is, only the route control unit 15 of the computer 10 may create and hold the route information list 152.

  Further, S506 and S520 in FIG. 2 may be executed at predetermined intervals to update the state of each communication path (see reference numerals 152 and 252) in the path information lists 152 and 152 to monitor the path failure. The contents of the route information lists 152 and 252 may be updated by executing S504 to 506 and S518 to S520 in FIG. 2 at predetermined intervals. By doing in this way, the computers 10 and 20 can dynamically add or delete the IP addresses of the network adapters 16, 17, 26, and 27 or the computers 10 and 20, or add or delete a route that accompanies a failure. Can respond to changes. Note that the path control units 15 and 25 may establish a plurality of path control connections for each communication path.

  According to the system of the present embodiment described above, in the environment where a plurality of communication paths exist between the computers 10 and 20, the same communication is performed on the forward path and the return path regarding the plurality of connections established between the applications 13 and 23. It can be a route. Further, the computers 10 and 20 can make the applications 13 and 23 recognize that the connection is between the same IP addresses even if the communication path is different for each connection. As a result, the applications 13 and 23 can provide the same service to the same computer even if the computers 20 and 10 are accessed using a plurality of IP addresses.

  Further, the computers 10 and 20 can continue communication on another communication path without causing the applications 13 and 23 to be aware of the failure when the communication path fails. Thereby, effective use of the network, load distribution, and reliability can be improved.

  The computers 10 and 20 according to the present embodiment can be realized by a communication path control program for executing the processing as described above, and the program is stored in a computer-readable storage medium (CD-ROM or the like). Can be provided. It is also possible to provide the program through a network such as the Internet.

It is a figure which shows the structure of the communication path control system of this Embodiment. It is a sequence diagram which shows operation | movement of the computers 10 and 20 of FIG. (A) is the figure which illustrated the path | route information list 152 after S506 of FIG. 2, (b) is the figure which illustrated the path | route information list 252 after S520 of FIG. It is a sequence diagram which shows the communication path | route setting process of S510 and S521 of FIG. 4A is a diagram illustrating the path management table 151 after execution of S808 in FIG. 4, FIG. 4B is a diagram illustrating the path management table 251 after execution of S803 in FIG. 4, and FIG. FIG. 10 is a diagram illustrating a route information list 600 which is another example of the route information list. (A) is the figure which illustrated the path | route management table 151 after the computer 10 of FIG. 1 established the 2nd connection (2nd connection), (b) is the figure which the computer 20 of FIG. It is the figure which illustrated the path | route management table 251 after establishing this connection (2nd connection).

Explanation of symbols

10,20 Computer (communication device)
11,21 CPU
12,22 Memory (storage unit)
13, 23 Application 15, 25 Route control unit 16, 17, 26, 27 Network adapter (interface unit)
30,40 network 31,41 route 151,251 route management table (route management information)
152,252,600 Route information list

Claims (5)

A communication path control method when a first communication device performs data communication with a second communication device that is a communication partner,
Stores path information indicating one or more communication paths having the address of the second communication apparatus as a destination address by a combination of an address held by the first communication apparatus and an address held by the second communication apparatus When the first communication device including the storage unit establishes a connection with the second communication device based on a request from the application of the first communication device,
A path control unit of the first communication device;
From one or more communication paths indicated in the path information, select a communication path to be used for a connection between applications of the first communication apparatus and the second communication apparatus,
A communication path setting request including connection information for communication using an address communicable on the selected communication path and connection information for application using an address used between the applications is sent to the second To the communication device,
A path control unit of the second communication device;
When the communication path setting request is received, path management information in which the connection information for application and the connection information for communication included in the communication path setting request are associated with each other is stored in the storage unit of the second communication device Remember
A communication path setting response is transmitted to the first communication device;
A path control unit of the first communication device;
When the communication path setting response is received from the second communication apparatus, the path management information included in the transmitted communication path setting request is stored in the storage unit of the first communication apparatus,
Based on the connection information for communication indicated in the route management information, establish a connection for communication with the second communication device,
When data communication is performed with the second communication device based on a request from the application of the first communication device, the path management information stored in the storage unit of the first communication device is used to Selecting communication connection information corresponding to the connection information of the connection requested by the application of the first communication device, performing data communication using the connection indicated in the selected connection information for communication,
Notifying the application of the first communication device that data communication has been performed through the connection requested by the application of the first communication device;
A path control unit of the second communication device;
When performing data communication with the first communication device based on a request from the application of the second communication device, the path management information stored in the storage unit of the second communication device is used to Selecting communication connection information corresponding to the connection information of the connection requested by the application of the communication device 2 and performing data communication using the connection indicated in the selected connection information for communication;
A communication path control method comprising: notifying an application of the second communication device that data communication is performed through a connection requested by the application of the second communication device. A path control unit of the second communication device;
When receiving the communication path setting request, refer to the path information provided in the second communication device, determine whether to respond to the communication path setting that is the target of the communication path setting request,
When it is determined not to respond to the communication route setting that is the target of the communication route setting request, a communication route having a transmission source of the communication route setting request as a destination address is selected from the communication routes registered in the route information; The selected communication path and the determination result are included in the communication path setting response and transmitted,
A path control unit of the first communication device;
Connection information for communication using an address capable of communicating the communication path included in the received communication path setting response when the communication path setting response is received and the determination result included in the communication path setting response is rejected And a communication path setting request including connection information for an application using an address used between the applications, to the second communication apparatus. Control method. The communication path information indicated in the path information includes, for each communication path, path status information indicating whether or not communication of the communication path is possible, the number of connections used in the communication path, a communication load in the communication path, and the communication At least one of the response performances in the path includes one,
When the first communication device selects a communication path to be used for the connection, the number of connections used for the communication path is the smallest among the communication paths that are communicable in the path state information. The communication path control method according to claim 1 or 2, wherein a communication path, a communication path having the smallest communication load in the communication path, or a communication path having the highest response performance in the communication path is selected. .   A communication path control program for causing a computer as a communication apparatus to execute the communication path control method according to any one of claims 1 to 3. A communication device that performs data communication with another communication device that is a communication partner,
An interface unit for performing data communication with other communication devices via a network;
A storage unit storing path information indicating one or more communication paths having a destination address as an address of the other communication apparatus as a combination of an address held by the own communication apparatus and an address held by the other communication apparatus; ,
When establishing a connection with the other communication device based on a request from an application of the own communication device, the own communication device and the other communication device are selected from one or more communication paths indicated in the path information. A communication path to be used for a connection between applications, connection information for communication using an address communicable on the selected communication path, connection information for an application using an address used between the applications, and When a communication path setting response that is a response to the communication path setting request is received from the other communication apparatus, the communication path setting request including the communication path setting request is transmitted to the other communication apparatus via the interface unit. The route management information included in the transmitted communication route setting request is stored in the storage unit of the own communication device Based on the communication connection information indicated in the route management information, establish a communication connection with the other communication device, and based on a request from the application of the own communication device, via the interface unit When performing data communication with the other communication device, communication information corresponding to the connection information of the connection requested by the application of the own communication device is obtained from the route management information stored in the storage unit of the own communication device. Select connection information, perform data communication using the connection indicated in the selected connection information for communication, and send data communication to the application of the communication device by the connection requested by the application of the communication device. A route control unit for notifying that it has been performed;
A communication apparatus comprising:

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