JP2010068051A - Relay server and relay communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for enabling each device to check a virtual network environment in a relay communication system in real time in the relay communication system where a remote LAN performs communication over a WAN. <P>SOLUTION: Relay servers 12, 22 relay communication between client terminals 11, 21. The relay servers 12 (22) creates relay group information, as is shown below, indicating the virtual private IP address of the relay servers 12, 22 and a connection establishment state and relay server information indicating the virtual private IP address of the client terminal 11 (21) communicable with the relay server 12 (22) and a connection establishment state to allow the entire relay communication system to share the relay group information and the relay server information. Each device in the relay communication system can share information on virtual private IP addresses and connection establishment states of all of the devices, and can flexibly execute communication, where the virtual private IP addresses have been designated as communication destinations. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a relay server and a relay communication system that enable a client terminal connected to a remote LAN (Local Area Network) to communicate over a WAN (Wide Area Network).

  A client terminal connected to a remote LAN may communicate over a WAN. A VPN (Virtual Private Network) can construct a network as if a remote LAN is directly connected. However, it is difficult for VPN to build a scalable and flexible network.

  The relay communication system disclosed in Patent Document 1 can construct a network as if a remote LAN is directly connected, like VPN. And unlike a VPN, a relay communication system is easy to construct a network with expandability and flexibility.

  The relay communication system includes a WAN and a plurality of LANs. Each LAN includes a relay server. Each relay server stores relay group information about a relay server included in the relay communication system and shared resource information about a resource shared by the relay communication system.

  When a client terminal connected to one LAN operates a resource stored in a client terminal connected to another LAN, the relay server connected to these LANs is based on the relay group information and the shared resource information. , Relay resource operations.

  The number of LANs included in the relay communication system may increase or decrease. Resources shared by the relay communication system may be updated. However, the relay communication system can update the relay group information and the shared resource information in response to these changes. And the relay communication system can construct | assemble a network with an expandability and flexibility corresponding to these changes.

JP 2008-129991 A

  In the relay communication system disclosed in Patent Document 1, the increase / decrease state and connection state of the LAN and client terminals may change. However, when the client terminal and the relay server specify the communication destination, a specific means for confirming the increase / decrease state and connection state of the device in real time is not disclosed. Furthermore, even if the increase / decrease state and the connection state of the device change, specific means by which the client terminal and the relay server can dynamically allocate a virtual IP (Internet Protocol) address is not disclosed.

  Therefore, in view of the above problems, in the relay communication system that enables a client terminal connected to a remote LAN to communicate over a WAN, the client terminal and the relay server specify a communication destination. It is an object of the present invention to provide a specific means for confirming an increase / decrease state and a connection state of devices in real time. It is another object of the present invention to provide a specific means by which a client terminal and a relay server can dynamically allocate a virtual IP address even when the increase / decrease state and connection state of devices change.

  In order to solve the above problem, the invention described in claim 1 is a first network, a second network, a first relay server connected to the first network, and a second relay connected to the second network. A relay communication system comprising: a server, wherein the first relay server and the second relay server are a relay group formed by the first relay server and the second relay server, and are used in the relay group A relay group information creating unit that creates relay group information indicating the first relay server activation information indicating the activation state of the first relay server, and The first registered in the first relay server including a connection state between one relay server and a first client terminal connected to the first network A first relay server information creating unit that creates first relay server information including first client terminal registration information relating to a client terminal, wherein the second relay server indicates a start state of the second relay server. Second relay server activation information and the second client terminal registered in the second relay server, including a connection state between the second relay server and the second client terminal connected to the second network. A second relay server information creation unit that creates second relay server information including two client terminal registration information, wherein the first relay server and the second relay server include the first relay server information and the second relay server information The relay server information including the second relay server information and the relay group information are shared between the first relay server and the second relay server. A virtual network address managed to be unique within the relay group is dynamically assigned to the first client terminal and the second client terminal at a predetermined timing with the inter-server sharing unit, and the assigned virtual network address A virtual address management unit for registering the information in the relay server information, wherein the first relay server transmits the relay group information and the relay server information between the first relay server and the first client terminal. A first inter-client-terminal sharing unit that is shared between the second relay server and the second client terminal. The second relay server shares the relay group information and the relay server information between the second relay server and the second client terminal. And a second inter-client-terminal sharing unit.

  According to a second aspect of the present invention, in the relay communication system according to the first aspect, the relay group information includes a relay server connection establishment as to whether the first relay server and the second relay server have established a connection. The first relay server information includes first client terminal connection establishment information as to whether or not the first client terminal has established a connection with the first relay server, and the second relay server The information includes second client terminal connection establishment information as to whether or not the second client terminal has established a connection with the second relay server.

  A third aspect of the present invention is the relay communication system according to the first or second aspect, wherein the first relay server is selected based on the relay group information and the relay server information. A communication execution unit that executes communication relayed by the first relay server, with the virtual network address specified as a communication destination, based on the relay group information and the relay server information.

  According to a fourth aspect of the present invention, in the relay communication system according to any one of the first to third aspects, the first relay server and the first client terminal include the relay group information, the relay server information, And a map display unit for displaying a map visually representing a connection establishment status and a virtual address in the current relay group.

  The relay communication system includes a first network and a second network. The first network includes a first relay server and a first client terminal. The second network includes a second relay server and a second client terminal. The first relay server and the second relay server relay communication between the first client terminal and the second client terminal.

  The first (second) relay server creates relay group information, first (second) relay server information, and client terminal information. The relay group information includes a relay group formed by the first relay server and the second relay server, a virtual network address assigned to the first relay server and the second relay server, and a connection between the first relay server and the second relay server. It is information indicating whether it is established. The first (second) relay server information includes a first (second) client terminal capable of communicating with the first (second) relay server, a virtual network address assigned to the first (second) client terminal, This is information indicating whether the first (second) client terminal has established a connection. The client terminal information is information indicating a connection environment of the first (second) client terminal in the first (second) network.

  The first (second) relay server can share the first relay server information and the second relay server information between the first relay server and the second relay server by referring to the relay group information. The first (second) relay server can create the relay server information by combining the first relay server information and the second relay server information. The first (second) relay server refers to each client terminal information so that the relay group information and the relay server information can be obtained between the first (second) relay server and the first (second) client terminal. Can share.

  Each device in the relay communication system can share information on the increase / decrease state and connection state of the device in real time. Each device in the relay communication system can share information on the virtual network address of the device and connection establishment in real time. Each device in the relay communication system can flexibly execute communication in which a virtual network address is designated as a communication destination in response to a change in the state of the relay communication system.

{Overall configuration of relay communication system}
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of a relay communication system. The relay communication system includes LANs 1 and 2 and WAN3. LANs 1 and 2 are small-scale networks constructed remotely. The WAN 3 is a large-scale network such as the Internet.

  The LAN 1 includes a client terminal 11 and a relay server 12. The LAN 2 includes a client terminal 21 and a relay server 22. The WAN 3 includes a SIP (Session Initiation Protocol) server 31.

  The client terminals 11 and 21 are personal computers or the like. The relay servers 12 and 22 relay communication between the client terminals 11 and 21. The SIP server 31 relays communication between the relay servers 12 and 22.

  In the present embodiment, SIP is used as a communication protocol between the relay servers 12 and 22, but a protocol other than SIP may be used. When a protocol other than SIP is used, communication between the relay servers 12 and 22 may be directly executed.

{Components of relay server}
FIG. 2 is a diagram showing components of the relay server 12 (22). The relay server 12 (22) includes an interface unit 121 (221), a control unit 122 (222), a database storage unit 123 (223), a relay group map display unit 127 (227), and a virtual LAN driver 128 (228). The A code without parentheses indicates a code in the relay server 12. Reference numerals with parentheses indicate reference numerals in the relay server 22.

  The interface unit 121 (221) performs communication with the client terminal 11 (21) connected to the LAN 1 (2) using the private IP address. The interface unit 121 (221) performs communication with the SIP server 31 connected to the WAN 3 using the global IP address.

  The control unit 122 (222) performs control for relaying communication between the client terminals 11 and 21. The control unit 122 (222) creates or updates the following information stored in the database storage unit 123 (223).

  The database storage unit 123 (223) includes a relay group information storage unit 124 (224), a relay server information storage unit 125 (225), and a client terminal information storage unit 126 (226). The relay group map display unit 127 (227) displays the relay group map on the relay server 12 (22) by referring to the relay group information and the relay server information. The virtual LAN driver 128 (228) registers the virtual private IP address of the relay server 12 (22) virtually allocated in the relay communication system. A method for assigning a virtual private IP address to each relay server in the relay communication system will be described later. Also, specific examples of the above information and relay group map will be described later.

{Components of client terminal}
FIG. 3 shows the components of the client terminal 11 (21). The client terminal 11 (21) includes an interface unit 111 (211), a control unit 112 (212), a web browser 113 (web server 213), a virtual LAN driver 114 (214), a database storage unit 115 (215), a relay group map. It is comprised from the display part 118 (218). Reference numerals without parentheses indicate reference numerals in the client terminal 11. Reference numerals with parentheses indicate reference numerals in the client terminal 21.

  The interface unit 111 (211) performs communication with the relay server 12 (22) connected to the LAN 1 (2) using the private IP address.

  The control unit 112 (212) performs control for executing communication between the client terminal 11 (21) and the relay server 12 (22).

  The control unit 112 (212) inputs or outputs information to be processed by the web browser 113 (web server 213). The web browser 113 requests content from the web server 213 via the WAN 3. The web server 213 provides content to the web browser 113 via the WAN 3.

  The virtual LAN driver 114 (214) registers the virtual private IP address of the client terminal 11 (21) virtually allocated in the relay communication system. A method of assigning a virtual private IP address to each client terminal in the relay communication system will be described later.

  The control unit 112 (212) creates or updates the following information stored in the database storage unit 115 (215). The database storage unit 115 (215) includes a relay group information storage unit 116 (216) and a relay server information storage unit 117 (217). The relay group map display unit 118 (218) displays the relay group map on the client terminal 11 (21) by referring to the relay group information and the relay server information. Specific examples of the above information and relay group map will be described later.

{Specific example of relay group information}
FIG. 4 is a diagram illustrating the relay group information 40 as a specific example of the relay group information. The relay group information is information indicating an outline of the relay server that constitutes the relay communication system.

  The relay group information 40 includes upper information 401 and lower information 402. The upper information 401 includes relay group virtual address information 403. The lower information 402 includes relay server virtual address information 404 and connection establishment information 405.

  The upper information 401 is information regarding the relay group at the upper level. “Id” indicates identification information of the relay group. “Lastmod” indicates the latest update time of the relay group information. “Name” indicates the name of the relay group. The relay group virtual address information 403 indicates a virtual private IP address (network address) of the relay group virtually allocated in the relay communication system. In the relay communication system, the subnet mask is set to “255.255.255.0”, and “*” is uniquely set to each device.

  The lower information 402 is information about the relay server at the lower level. “Id” indicates identification information of the relay server. The relay server virtual address information 404 indicates a virtual private IP address of the relay server that is virtually allocated in the relay communication system. The connection establishment information 405 is information about whether or not a connection is established between the relay servers via the WAN 3.

  The relay group information 40 is stored in the relay group information storage units 124, 224, 116, and 216. That is, the relay group information 40 is shared by the relay servers 12 and 22 and the client terminals 11 and 21.

  When a connection for IP communication using a virtual address is established between the relay servers via the WAN 3, connection establishment information 405 is described. When a connection for IP communication using a virtual address is not established between the relay servers via the WAN 3, the connection establishment information 405 is not described. As a result, information about whether or not a connection for IP communication using a virtual address is established between the relay servers via the WAN 3 is shared as the entire relay communication system. Further, information about the virtual private IP address of the relay server is shared as the entire relay communication system.

{Specific example of relay server information}
FIG. 5 is a diagram showing relay server information 50 as a specific example of the relay server information. The relay server information is information that indicates details of the relay server that constitutes the relay communication system, and is an information that indicates an outline of the client terminal that constitutes the relay communication system.

  The relay server information 50 includes upper information 501-1 and 501-2 and lower information 502-1 and 502-2. The upper information 501-1 and 501-2 include relay server activation information 503-1 and 503-2, respectively. The lower information 502-1 and 502-2 indicate client terminal virtual address information 504-1 and 504-2, connection establishment information 505-1 and 505-2, and whether the client terminal is logged in to the relay server, respectively. Client terminal site information 506-1 and 506-2 are included.

  The upper information 501-1 and 501-2 are information on the relay server at the upper level. “Id” indicates identification information of the relay server. “Name” indicates the name of the relay server. The relay server activation information 503-1 and 503-2 are information about whether the relay server is activated.

  The lower information 502-1 and 502-2 are information about the lower client terminals. “Div” indicates a department name of the client terminal. “Group” indicates identification information of the relay group to which the client terminal belongs. “Id” indicates identification information of the client terminal. “Name” indicates the name of the client terminal.

  The client terminal virtual address information 504-1 and 504-2 indicate virtual private IP addresses of client terminals virtually allocated in the relay communication system. The connection establishment information 505-1 and 505-2 are information about whether or not a connection for IP communication using a virtual address is established between a client terminal and a relay server in the same LAN. Client terminal site information 506-1 and 506-2 indicate identification information of the relay server to which the client terminal is logged on.

  The relay server information 50 is stored in the relay server information storage units 125, 225, 117, and 217. That is, the relay server information 50 is shared by the relay servers 12 and 22 and the client terminals 11 and 21.

  When the relay server is activated, the relay server activation information 503-1 and 503-2 are “active”. When the relay server is not activated, the relay server activation information 503-1 and 503-2 are blank. Thereby, information about whether the relay server is activated is shared as the whole relay communication system.

  When the client terminal is logged on to the relay server, client terminal site information 506-1 and 506-2 are described. When the client terminal is not logged on to the relay server, the client terminal site information 506-1 and 506-2 are not described. As a result, information about whether the client terminal is logged on to the relay server is shared as the entire relay communication system.

  When a connection for IP communication using a virtual address is established between a client terminal and a relay server in the same LAN, connection establishment information 505-1 and 505-2 are described. When a connection for IP communication using a virtual address is not established between a client terminal and a relay server in the same LAN, connection establishment information 505-1 and 505-2 are not described. As a result, information about whether or not a connection for IP communication using a virtual address is established between the client terminal and the relay server in the same LAN is shared as the entire relay communication system. Further, information about the virtual private IP address of the client terminal is shared as the entire relay communication system.

{Specific examples of client terminal information}
FIG. 6 is a diagram showing client terminal information 60 and 70 as specific examples of the client terminal information. The client terminal information is information indicating details of the client terminals that constitute the relay communication system.

  The client terminal information 60 and 70 includes client terminal address information 601 and 701, client terminal expiration date information 602 and 702, and client terminal port information 603 and 703, respectively. The client terminal address information 601 and 701 do not necessarily match the client terminal virtual address information 504-1 and 504-2, respectively.

  “Div” indicates a department name of the client terminal. “Group” indicates identification information of the relay group to which the client terminal belongs. The client terminal address information 601 and 701 indicate the IP addresses of the client terminals that are uniquely assigned only in the LANs 1 and 2, respectively. The client terminal expiration date information 602 and 702 indicates the registration expiration date of the client terminal. “Id” indicates identification information of the client terminal. “Name” indicates the name of the client terminal. “Pass” indicates a password of the client terminal. The client terminal port information 603, 703 indicates the port number of the client terminal.

  The client terminal information 60 is stored only in the client terminal information storage unit 126, and the client terminal information 70 is stored only in the client terminal information storage unit 226. That is, the client terminal information 60 is held only by the relay server 12, and the client terminal information 70 is held only by the relay server 22.

{Information sharing flow}
FIG. 7 to FIG. 9 are diagrams illustrating a flow of processing in which relay group information and relay server information are shared. The relay servers 12 and 22 participate in the relay communication system. Then, the user of the client terminal 11 logs on to the relay server 12, and the user of the client terminal 21 logs on to the relay server 22. Further, a connection for IP communication using a virtual address is established in each section between the relay servers 12 and 22, between the client terminal 11 and the relay server 12, and between the client terminal 21 and the relay server 22. Is done.

[Processing flow from step S1 to step S2]
The administrator of the relay server 12 and the administrator of the relay server 22 make a contract for building a group of relay communication systems between the LANs 1 and 2. The administrator of the relay server 12 and the administrator of the relay server 22 set “255.255.255.0” as the subnet mask and set “192.168.0. *” As the virtual private IP address. , “*” Is signed to set a unique numerical value for each device.

  The administrator of the relay server 12 creates an account for the user of the client terminal 11 (step S1: CreateAccount ()). The control unit 122 creates relay server information 51-1 and stores it in the relay server information storage unit 125.

  The administrator of the relay server 22 creates an account for the user of the client terminal 21 (Step S2: CreateAccount ()). The control unit 222 creates relay server information 51-2 and stores it in the relay server information storage unit 225.

  Through the above processing flow, the relay server 12 holds the relay server information 51-1. The relay server 22 has relay server information 51-2.

  The first frame in FIG. 10 shows relay server information 51-1. The upper information 511-1 is information about the relay server 12 at the upper level. As “id”, “relay-server-1@abc.net” is set. “RELAY SERVER 1” is set as “name”. “Active” is set as the relay server activation information 513-1. That is, the relay server 12 is activated.

  The lower information 512-1 is information about the client terminal 11 at the lower level. “Software” is set as “div”. “20070402133100@relay-server-1.abc.net” is set as “group”. As “id”, “client-1@relay-server-1.abc.net” is set. “CLIENT 1” is set as “name”. The client terminal site information 516-1 is blank. That is, the user of the client terminal 11 is not logged on to the relay server 12. Therefore, client terminal virtual address information and connection establishment information are not yet described.

  The second frame in FIG. 10 shows the relay server information 51-2. The upper information 511-2 is information about the relay server 22 at the upper level. As “id”, “relay-server-2@abc.net” is set. “RELAY SERVER 2” is set as “name”. “Active” is set as the relay server activation information 513-2. That is, the relay server 22 is activated.

  The lower information 512-2 is information about the client terminal 21 that is a lower level. “Software” is set as “div”. “20070402133100@relay-server-1.abc.net” is set as “group”. As “id”, “client-2@relay-server-2.abc.net” is set. “CLIENT 2” is set as “name”. The client terminal site information 516-2 is blank. That is, the user of the client terminal 21 is not logged on to the relay server 22. Therefore, client terminal virtual address information and connection establishment information are not yet described.

  FIG. 11 shows a relay group map. At this time, since no relay group has been formed yet, the relay group map display units 127, 227, 118, and 218 display a message indicating that there is no relay group to be displayed.

[Processing flow from step S3 to step S4]
In the following description, communication between the relay servers 12 and 22 is relayed by the SIP server 31. A method in which the relay server 12 (22) performs communication with the relay server 22 (12) via the SIP server 31 will be described.

  The relay server 12 (22) transmits, for example, data in which the account of the relay server 22 (12) is designated as a communication destination to the SIP server 31. The SIP server 31 associates the accounts of the relay servers 12 and 22 with the global IP addresses of the relay servers 12 and 22, respectively. The SIP server 31 acquires the global IP address of the relay server 22 (12) based on the account of the relay server 22 (12). The SIP server 31 transmits, for example, data in which the global IP address of the relay server 22 (12) is designated as a communication destination to the relay server 22 (12).

  The relay server 12 requests the relay server 22 to construct a group of the relay communication system (step S3: SetGroup ()). The control unit 122 creates the relay group information 42 and stores it in the relay group information storage unit 124. The control unit 222 creates the relay group information 42 and stores it in the relay group information storage unit 224.

  The relay server 12 requests the relay server 22 to exchange relay server information (step S4: exchange (db)). The relay server 12 transmits a copy of the relay server information 51-1 to the relay server 22. The relay server 22 transmits a copy of the relay server information 51-2 to the relay server 12.

  The control unit 122 creates the relay server information 52 by duplicating the relay server information 51-2 and combining the relay server information 51-1, and stores the relay server information 52 in the relay server information storage unit 125. The control unit 222 creates the relay server information 52 by combining the relay server information 51-1 and the relay server information 51-2, and stores the relay server information 52 in the relay server information storage unit 225.

  The control unit 122 creates client terminal information 62 and stores it in the client terminal information storage unit 126. The control unit 222 creates client terminal information 72 and stores it in the client terminal information storage unit 226. The creation process and storage process of the client terminal information 62 are executed in step S1, and the creation process and storage process of the client terminal information 72 are executed in step S2.

  Through the above processing flow, the relay server 12 holds the relay group information 42, the relay server information 52, and the client terminal information 62. The relay server 22 has relay group information 42, relay server information 52, and client terminal information 72. The relay group information 42 and the relay server information 52 are shared by the relay servers 12 and 22.

  The first frame in FIG. 12 shows the relay group information 42. The upper information 421 is information about the relay group at the upper level. As “id”, “20070402133100@relay-server-1.abc.net” is set. As “lastmod”, “20070402133100” is set. “GROUP 1” is set as “name”. However, no connection is established between the relay servers 12 and 22. Therefore, the relay group virtual address information is not yet described.

  The lower information 422 is information about the relay servers 12 and 22 that are lower. As “id”, “relay-server-1@abc.net” and “relay-server-2@abc.net” are set. However, a connection for IP communication using a virtual address is not established between the relay servers 12 and 22. Therefore, the relay server virtual address information and connection establishment information are not yet described.

  The second frame in FIG. 12 shows the relay server information 52. The upper information 521-1 and 521-2 are the same as the upper information 511-1 and 511-2 in FIG. 10, respectively. The lower information 522-1 and 522-2 are the same as the lower information 512-1 and 512-2 in FIG. 10, respectively.

  The third frame in FIG. 12 shows client terminal information 62. “Software” is set as “div”. “20070402133100@relay-server-1.abc.net” is set as “group”. As “id”, “client-1@relay-server-1.abc.net” is set. “CLIENT 1” is set as “name”. “Client-1” is set as “pass”.

  The client terminal address information 621 is blank. “0” is set as the client terminal expiration date information 622. The client terminal port information 623 is blank. That is, the user of the client terminal 11 is not logged on to the relay server 12.

  The fourth frame in FIG. 12 shows client terminal information 72. “Software” is set as “div”. “20070402133100@relay-server-1.abc.net” is set as “group”. As “id”, “client-2@relay-server-2.abc.net” is set. “CLIENT 2” is set as “name”. “Client-2” is set as “pass”.

  The client terminal address information 721 is blank. “0” is set as the client terminal expiration date information 722. The client terminal port information 723 is blank. That is, the user of the client terminal 21 is not logged on to the relay server 22.

  FIG. 13 shows a relay group map. The relay group map display unit 127 of the relay server 12 and the relay group map display unit 227 of the relay server 22 display the relay group map by referring to the relay group information 42 and the relay server information 52.

  The relay server 12 requests the relay server 22 to construct a group of relay communication systems. Therefore, the relay group map of FIG. 11 is synthesized and the relay group map of FIG. 13 is displayed. However, in the relay group information 42, connection establishment information has not been described yet. For this reason, “connection not established” and a broken line there between are described between “relay server 12” and “relay server 22”.

[Processing flow from step S5 to step S6]
The relay server 12 executes call control on the relay server 22 (step S5: INVITE ()) and requests connection establishment (step S6: connect ()). The control unit 122 creates the relay group information 43 by updating the relay group information 42 and stores it in the relay group information storage unit 124. When the connection between the relay server 12 and the relay server 22 is established, the relay server 12 and the relay server 22 allocate respective virtual private addresses. The control unit 222 updates the relay group information 42 to create the relay group information 43 and stores it in the relay group information storage unit 224. The control unit 122 does not update the relay server information 52 and the client terminal information 62. The control unit 222 does not update the relay server information 52 and the client terminal information 72.

  Through the above processing flow, the relay server 12 holds the relay group information 43, the relay server information 52, and the client terminal information 62. The relay server 22 has relay group information 43, relay server information 52, and client terminal information 72. The relay group information 43 and the relay server information 52 are shared by the relay servers 12 and 22.

  The first frame in FIG. 14 shows the relay group information 43. The updated part is indicated by the underlined part. The relay server 12 establishes a connection for IP communication using a virtual address with the relay server 22.

  The control units 122 and 222 set the relay group virtual address information 433 of the upper information 431 to “192.168.0. *” Based on the contract concluded by the administrator of the relay servers 12 and 22. In the relay communication system, “*” is uniquely set in each device.

  Based on the relay group virtual address information 433, the control units 122 and 222 set the relay server virtual address information 434 for the relay servers 12 and 22 in the lower information 432 to different numerical values. The control unit 122 sets “*” to “1”, and sets the relay server virtual address information 434 for the relay server 12 to “192.168.0.1”. The control unit 222 sets “*” to “2”, and sets the relay server virtual address information 434 for the relay server 22 to “192.168.0.2”.

  The control unit 122 sets the connection establishment information 435 for the relay server 12 in the lower information 432 to “s1”. The control unit 222 sets the connection establishment information 435 for the relay server 22 in the lower information 432 to “s2”. In FIG. 7, “Transaction” is set to “s1” and “s2” for the sockets of the relay servers 12 and 22 among the connections for IP communication using the virtual addresses between the relay servers 12 and 22, respectively. ing.

  “GroupID” indicates identification information of the relay group with which the connection is established, and is set to “2007040402133100@relay-server-1.abc.net”. “MediaSession” is set to “socket”. The above two types of information are the same in FIG. 7 and FIG.

  The second frame in FIG. 14 shows the relay server information 52. In the processing flow from step S5 to step S6, the user of the client terminal 11 is not logged on to the relay server 12, and the user of the client terminal 21 is not logged on to the relay server 22. 52 is never updated.

  The third frame in FIG. 14 shows client terminal information 62. In the processing flow from step S5 to step S6, since the user of the client terminal 11 is not logged on to the relay server 12, the client terminal information 62 is not updated.

  The fourth frame in FIG. 14 shows client terminal information 72. In the processing flow from step S5 to step S6, since the user of the client terminal 21 is not logged on to the relay server 22, the client terminal information 72 is not updated.

  FIG. 15 shows a relay group map. The relay group map display unit 127 of the relay server 12 and the relay group map display unit 227 of the relay server 22 display the relay group map by referring to the relay group information 43 and the relay server information 52.

  The relay server 12 is executing call control to the relay server 22 and requesting establishment of a connection for IP communication using a virtual address. In the relay group information 43, the relay server virtual address information 434 and the connection establishment information 435 are already described. For this reason, the virtual private IP addresses of the relay servers 12 and 22 have been described. Then, “connection establishment” and a side solid line are described between “relay server 12” and “relay server 22”.

[Processing flow from step S7 to step S9]
Please refer to FIG. The user of the client terminal 11 inputs “client-1@relay-server-1.abc.net” as the identification information of the client terminal 11 and inputs “client-1” as the password of the client terminal 11. . The user of the client terminal 11 logs on to the relay server 12 (step S7: REGISTER (ID, PASS)). The control unit 122 performs authentication of the user of the client terminal 11 by referring to the client terminal information 62.

  The control unit 122 accepts logon of the user of the client terminal 11. The control unit 122 creates the relay server information 54 by updating the relay server information 52 and stores it in the relay server information storage unit 125. When the client terminal 11 logs on to the relay server 12, the relay server 12 assigns a virtual private address of the client terminal 11. The control unit 122 creates client terminal information 64 by updating the client terminal information 62 and stores the client terminal information 64 in the client terminal information storage unit 126. The control unit 122 does not update the relay group information 43.

  The client terminal 11 requests the relay server 12 to provide relay group information and relay server information (step S8: get ()). The relay server 12 transmits a copy of the relay group information 43 and the relay server information 54 to the client terminal 11. The client terminal 11 stores the relay group information 43 in the relay group information storage unit 116 and stores the relay server information 54 in the relay server information storage unit 117.

  The control unit 122 determines the relay server to be notified that the relay server information 52 has been updated to the relay server information 54 by referring to the relay group information 43 and the relay server information 54. The control unit 122 determines the relay server 22 whose relay server activation information 543-2 of the relay server information 54 is “active” as a relay server to be notified.

  The relay server 12 notifies the relay server 22 that the relay server information 52 has been updated to the relay server information 54 (step S9: NOTIFY ()). The control unit 222 updates the relay server information 52 to create the relay server information 54 and stores it in the relay server information storage unit 225.

  The control unit 222 refers to the client terminal information 72 to determine a client terminal to be notified that the relay server information 52 has been updated to the relay server information 54. The control unit 222 does not determine the client terminal 21 in which the client terminal address information 721 of the client terminal information 72 is blank and the client terminal port information 723 of the client terminal information 72 is blank as a client terminal to be notified. .

  Through the above processing flow, the relay server 12 holds the relay group information 43, the relay server information 54, and the client terminal information 64. The relay server 22 has relay group information 43, relay server information 54, and client terminal information 72. The client terminal 11 has relay group information 43 and relay server information 54. The relay group information 43 and the relay server information 54 are shared by the relay servers 12 and 22 and the client terminal 11.

  The first frame in FIG. 16 shows the relay group information 43. In the processing flow from step S7 to step S9, the relay group information 43 is not updated because a new relay server does not participate in the relay communication system.

  The second frame in FIG. 16 shows the relay server information 54. The updated part is indicated by the underlined part. The user of the client terminal 11 is logged on to the relay server 12. Therefore, the client terminal site information 546-1 of the lower information 542-1 is fixed to “relay-server-1@abc.net”.

  The control unit 122 sets “*” to “11”, and sets the client terminal virtual address information 544-1 for the client terminal 11 of the lower information 542-1 to “192.168.0.11”. ing. Here, the virtual private IP address does not overlap with the already set virtual private IP address.

  The control unit 122 sets the connection establishment information 545-1 for the client terminal 11 of the lower information 542-1 to a blank. That is, a connection for IP communication using a virtual address has not yet been established between the client terminal 11 and the relay server 12.

  The third frame in FIG. 16 shows client terminal information 64. The updated part is indicated by the underlined part. The user of the client terminal 11 is logged on to the relay server 12. Therefore, the client terminal address information 641 is fixed to “192.168.10.2”. Here, for the client terminal 11, the physical private IP address “192.168.10.2” does not match the virtual private IP address “192.168.0.11”. Further, the client terminal expiration date information 642 is determined to be “1213935960484”. Further, the client terminal port information 643 is fixed to “5070”.

  The fourth frame in FIG. 16 shows client terminal information 72. In the processing flow from step S7 to step S9, since the user of the client terminal 21 is not logged on to the relay server 22, the client terminal information 72 is not updated.

  FIG. 17 shows a relay group map. The relay group map display unit 118 of the client terminal 11, the relay group map display unit 127 of the relay server 12, and the relay group map display unit 227 of the relay server 22 refer to the relay group information 43 and the relay server information 54 for relaying. Display the group map.

  The user of the client terminal 11 is logged on to the relay server 12. In the relay server information 54, the client terminal virtual address information 544-1 has already been described. Therefore, the virtual private IP address of the client terminal 11 has been described. However, in the relay server information 54, the connection establishment information 545-1 is not yet described. Therefore, “connection establishment” and the adjacent solid line are not described between “client terminal 11” and “relay server 12”.

[Processing flow from step S10 to step S13]
The user of the client terminal 21 inputs “client-2@relay-server-2.abc.net” as identification information of the client terminal 21, and inputs “client-2” as the password of the client terminal 21. . The user of the client terminal 21 logs on to the relay server 22 (step S10: REGISTER (ID, PASS)). The control unit 222 performs authentication of the user of the client terminal 21 by referring to the client terminal information 72.

  The control unit 222 accepts logon of the user of the client terminal 21. The control unit 222 updates the relay server information 54 to create the relay server information 55 and stores it in the relay server information storage unit 225. When the client terminal 21 logs on to the relay server 22, the relay server 22 assigns the virtual private address of the client terminal 21. The control unit 222 updates the client terminal information 72 to create client terminal information 75 and stores it in the client terminal information storage unit 226. The control unit 222 does not update the relay group information 43.

  The client terminal 21 requests the relay server 22 to provide relay group information and relay server information (step S11: get ()). The relay server 22 transmits a copy of the relay group information 43 and the relay server information 55 to the client terminal 21. The client terminal 21 stores the relay group information 43 in the relay group information storage unit 216, and stores the relay server information 55 in the relay server information storage unit 217.

  The control unit 222 refers to the relay group information 43 and the relay server information 55 to determine a relay server to be notified that the relay server information 54 has been updated to the relay server information 55. The control unit 222 determines the relay server 12 whose relay server activation information 553-1 of the relay server information 55 is “active” as a relay server to be notified.

  The relay server 22 notifies the relay server 12 that the relay server information 54 has been updated to the relay server information 55 (step S12: NOTIFY ()). The control unit 122 creates the relay server information 55 by updating the relay server information 54 and stores it in the relay server information storage unit 125.

  The control unit 122 refers to the client terminal information 64 to determine a client terminal to be notified that the relay server information 54 has been updated to the relay server information 55. The control unit 122 determines the client terminal 11 in which the client terminal address information 641 of the client terminal information 64 is determined and the client terminal port information 643 of the client terminal information 64 is determined as a client terminal to be notified.

  The relay server 12 notifies the client terminal 11 that the relay server information 54 has been updated to the relay server information 55 (step S13: NOTIFY ()). The control unit 112 creates the relay server information 55 by updating the relay server information 54 and stores it in the relay server information storage unit 117.

  Through the above processing flow, the relay server 12 holds the relay group information 43, the relay server information 55, and the client terminal information 64. The relay server 22 has relay group information 43, relay server information 55, and client terminal information 75. The client terminal 11 has relay group information 43 and relay server information 55. The client terminal 21 has relay group information 43 and relay server information 55. The relay group information 43 and the relay server information 55 are shared by the relay servers 12 and 22 and the client terminals 11 and 21.

  The first frame in FIG. 18 shows the relay group information 43. In the processing flow from step S10 to step S13, the relay group information 43 is not updated because a new relay server does not participate in the relay communication system.

  The second frame in FIG. 18 shows the relay server information 55. The updated part is indicated by the underlined part. The user of the client terminal 21 is logged on to the relay server 22. Therefore, the client terminal site information 556-2 of the lower information 552-2 is fixed to “relay-server-2@abc.net”.

  The control unit 222 sets “*” to “12”, and sets the client terminal virtual address information 554-2 for the client terminal 21 of the lower information 552-2 to “192.168.0.12”. ing. Here, the virtual private IP address does not overlap with the already set virtual private IP address.

  The control unit 222 sets the connection establishment information 555-2 for the client terminal 21 in the lower information 552-2 to a blank. That is, a connection for IP communication using a virtual address has not yet been established between the client terminal 21 and the relay server 22.

  The third frame in FIG. 18 shows client terminal information 64. In the processing flow from step S10 to step S13, since the user of the client terminal 11 has not logged off from the relay server 12, the client terminal information 64 is not updated.

  The fourth frame in FIG. 18 shows client terminal information 75. The updated part is indicated by the underlined part. The user of the client terminal 21 is logged on to the relay server 22. Therefore, the client terminal address information 751 is fixed at “192.168.1.10”. Here, for the client terminal 21, the physical private IP address “192.168.1.10” does not match the virtual private IP address “192.168.0.12”. Further, the client terminal expiration date information 752 is fixed to “1213935978484”. Further, the client terminal port information 753 is fixed to “5070”.

  FIG. 19 shows a relay group map. The relay group map display unit 118 of the client terminal 11, the relay group map display unit 218 of the client terminal 21, the relay group map display unit 127 of the relay server 12, and the relay group map display unit 227 of the relay server 22 include the relay group information 43 and The relay group map is displayed by referring to the relay server information 55.

  The user of the client terminal 21 is logged on to the relay server 22. In the relay server information 55, the client terminal virtual address information 554-2 is already described. Therefore, the virtual private IP address of the client terminal 21 has been described. However, in the relay server information 55, connection establishment information 555-2 is not yet described. Therefore, “connection establishment” and the adjacent solid line are not described between “client terminal 21” and “relay server 22”.

[Flow of processing from step S14 to step S17]
Please refer to FIG. The client terminal 11 performs call control on the relay server 12 (step S14: INVITE ()) and requests establishment of a connection for IP communication using a virtual address (step S15: connect ()). . The control units 122 and 112 create the relay server information 56 by updating the relay server information 55 and store them in the relay server information storage units 125 and 117, respectively. The control unit 122 does not update the relay group information 43 and the client terminal information 64. The control unit 112 does not update the relay group information 43.

  The process flow from step S16 to step S17 is executed in the same manner as steps S9, S12, and S13. The relay server 12 notifies the relay server 22 that the relay server information 55 has been updated to the relay server information 56 (step S16: NOTIFY ()). The relay server 22 notifies the client terminal 21 that the relay server information 55 has been updated to the relay server information 56 (step S17: NOTIFY ()).

  Through the above processing flow, the relay server 12 holds the relay group information 43, the relay server information 56, and the client terminal information 64. The relay server 22 has relay group information 43, relay server information 56, and client terminal information 75. The client terminal 11 has relay group information 43 and relay server information 56. The client terminal 21 has relay group information 43 and relay server information 56. The relay group information 43 and the relay server information 56 are shared by the relay servers 12 and 22 and the client terminals 11 and 21.

  The first frame in FIG. 20 shows the relay group information 43. In the processing flow from step S14 to step S17, the relay group information 43 is not updated because a new relay server does not participate in the relay communication system.

  The second frame in FIG. 20 shows the relay server information 56. The client terminal 11 has established a connection for IP communication using a virtual address with respect to the relay server 12.

  The control units 122 and 112 set the connection establishment information 565-1 of the lower information 562-1 to “c1”. In FIG. 9, “Transaction” is set to “c1” for the sockets of the client terminal 11 and the relay server 12 among the connections between the client terminal 11 and the relay server 12. “GroupID” and “MediaSession” are as described above.

  Here, the socket of the relay server 12 in the connection for IP communication using the virtual address between the client terminal 11 and the relay server 12, and the IP using the virtual address between the relay server 12 and the relay server 22 are used. The sockets of the relay server 12 in the communication connection are mutually different sockets. However, these sockets are related by the same groupID.

  The third frame in FIG. 20 shows client terminal information 64. In the processing flow from step S14 to step S17, since the user of the client terminal 11 has not logged off from the relay server 12, the client terminal information 64 is not updated.

  The fourth frame in FIG. 20 shows client terminal information 75. In the processing flow from step S14 to step S17, since the user of the client terminal 21 has not logged off from the relay server 22, the client terminal information 75 is not updated.

  FIG. 21 shows a relay group map. The relay group map display unit 118 of the client terminal 11, the relay group map display unit 218 of the client terminal 21, the relay group map display unit 127 of the relay server 12, and the relay group map display unit 227 of the relay server 22 include the relay group information 43 and The relay group map is displayed by referring to the relay server information 56.

  The client terminal 11 has established a connection for IP communication using a virtual address with respect to the relay server 12. In the relay server information 56, connection establishment information 565-1 is already described. Therefore, “connection establishment” and a solid line along the side are described between “client terminal 11” and “relay server 12”.

[Flow of processing from step S18 to step S21]
The client terminal 21 performs call control on the relay server 22 (step S18: INVITE ()) and requests establishment of a connection for IP communication using a virtual address (step S19: connect ()). . The control units 222 and 212 update the relay server information 56 to create relay server information 57 and store them in the relay server information storage units 225 and 217, respectively. The control unit 222 does not update the relay group information 43 and the client terminal information 75. The control unit 212 does not update the relay group information 43.

  The process flow from step S20 to step S21 is executed in the same manner as steps S9, S12, and S13. The relay server 22 notifies the relay server 12 that the relay server information 56 has been updated to the relay server information 57 (step S20: NOTIFY ()). The relay server 12 notifies the client terminal 11 that the relay server information 56 has been updated to the relay server information 57 (step S21: NOTIFY ()).

  Through the above processing flow, the relay server 12 holds the relay group information 43, the relay server information 57, and the client terminal information 64. The relay server 22 has relay group information 43, relay server information 57, and client terminal information 75. The client terminal 11 has relay group information 43 and relay server information 57. The client terminal 21 has relay group information 43 and relay server information 57. The relay group information 43 and the relay server information 57 are shared by the relay servers 12 and 22 and the client terminals 11 and 21.

  The first frame in FIG. 22 shows the relay group information 43. In the process flow from step S18 to step S21, the relay group information 43 is not updated because a new relay server does not participate in the relay communication system.

  The second frame in FIG. 22 shows the relay server information 57. The client terminal 21 establishes a connection for IP communication using a virtual address with respect to the relay server 22.

  The control units 222 and 212 set the connection establishment information 575-2 of the lower information 572-2 to “c2”. In FIG. 9, “Transaction” is set to “c2” for the sockets of the client terminal 21 and the relay server 22 in the IP communication connection using the virtual address between the client terminal 21 and the relay server 22. Yes. “GroupID” and “MediaSession” are as described above.

  Here, the socket of the relay server 22 in the connection for IP communication using the virtual address between the client terminal 21 and the relay server 22 and the IP using the virtual address between the relay server 12 and the relay server 22 are used. The sockets of the relay server 22 in the communication connection are mutually different sockets. However, these sockets are related by the same groupID.

  The third frame in FIG. 22 shows client terminal information 64. In the processing flow from step S18 to step S21, since the user of the client terminal 11 has not logged off from the relay server 12, the client terminal information 64 is not updated.

  The fourth frame in FIG. 22 shows client terminal information 75. In the processing flow from step S18 to step S21, since the user of the client terminal 21 has not logged off from the relay server 22, the client terminal information 75 is not updated.

  FIG. 23 shows a relay group map. The relay group map display unit 118 of the client terminal 11, the relay group map display unit 218 of the client terminal 21, the relay group map display unit 127 of the relay server 12, and the relay group map display unit 227 of the relay server 22 include the relay group information 43 and The relay group map is displayed by referring to the relay server information 57.

  The client terminal 21 establishes a connection for IP communication using a virtual address with respect to the relay server 22. In the relay server information 57, connection establishment information 575-2 is already described. Therefore, “connection establishment” and a side solid line are described between “client terminal 21” and “relay server 22”.

{Summary of information sharing}
In a relay communication system, the increase / decrease state and connection state of LANs and client terminals may change. Therefore, when one relay server recognizes the state change, it immediately updates the relay group information, the relay server information, and the client terminal information.

  Then, the one relay server immediately notifies the other relay servers described in the relay group information and the relay server information that the relay group information and the relay server information are updated. Further, the one relay server immediately notifies the client terminal described in the client terminal information that the relay group information and the relay server information are updated.

  However, if one relay server determines that another relay server is not connected even if the other relay server is described in the relay group information and relay server information, it immediately notifies the other relay server. Never do. Furthermore, even if the client terminal is described in the client terminal information, the one relay server does not immediately notify the client terminal when it is determined that the client terminal is not connected.

  The administrator of one relay server determines how to assign a virtual private IP address to each device by negotiating with the administrator of another relay server. One relay server determines the virtual private IP address of its own device by communicating with other relay servers so that the virtual private IP address of each device does not overlap. The relay server determines the virtual private IP address of the client terminal so that the virtual private IP address of each device does not overlap by communicating with the client terminal that logs on to the own device.

  Information about the virtual private IP address of each device is included in the relay group information and the relay server information. Information about the connection establishment state for IP communication using the virtual address of each device is included in the relay group information and the relay server information. When these pieces of information of each device change, the relay group information and the relay server information are updated throughout the relay communication system.

  Thereby, the information about the increase / decrease state and connection state of the LAN and the client terminal is shared in real time as the entire relay communication system. Information on the virtual private IP address of each device and information on the connection establishment state for IP communication using the virtual address of each device are shared in real time as the entire relay communication system. Furthermore, all the information described above is displayed in real time on each device.

  In the above embodiment, when a connection is established between the relay servers 12 and 22, or when the client terminals 11 and 21 log on to the relay servers 12 and 22, the relay servers 12 and 22 are connected to each server. And dynamically assigning virtual private addresses to each terminal. However, the timing for assigning the virtual address is not limited to this. For example, a virtual address may be assigned to all registered client terminals at the time when a group is formed, or a virtual address may be assigned when a relay server or client terminal is created. . Even in such a case, it is possible to determine whether or not communication using the virtual address is possible by checking the logon state.

  In the above embodiment, all relay servers and all client terminals have virtual LAN drivers and use virtual addresses, but only some servers and client terminals have virtual LAN drives. It may be. A WEB server using a virtual LAN driver may exist in the relay group.

{Flow of data transmission / reception}
FIG. 24 is a diagram showing a flow of data transmission / reception after information sharing. After information sharing, the relay group information 43, relay server information 57, and client terminal information 64 and 75 shown in FIG. 22 are stored, and the relay group map shown in FIG. 23 is displayed. The web browser 113 requests content from the web server 213. The web server 213 provides content to the web browser 113.

[Processing flow from step S22 to step S25]
Refer to FIG. The virtual LAN driver 114 and the web browser 113 are activated prior to content transmission / reception. The virtual LAN driver 114 acquires “192.168.0.11” as the virtual private IP address of the client terminal 11 based on the relay server information 57 stored in the relay server information storage unit 117 (step S22: open). (192.168.0.11)). The web browser 113 acquires “192.168.0.11” as the virtual private IP address of the client terminal 11 in the same manner as in step S22 (step S24: start (192.168.0.11)).

  The virtual LAN driver 214 and the web server 213 are activated prior to content transmission / reception. The virtual LAN driver 214 acquires “192.168.0.12” as the virtual private IP address of the client terminal 21 based on the relay server information 57 stored in the relay server information storage unit 217 (step S23: open). (192.168.0.12)). The web server 213 acquires “192.168.0.12” as the virtual private IP address of the client terminal 21 as in step S23 (step S25: start (192.168.0.12)).

[Processing flow of step S26]
The web browser 113 outputs content request information whose virtual private IP address of the transmission destination is “192.168.0.12” to the virtual LAN driver 114 (step S26: http (192.168.8.0). .12)).

  The virtual LAN driver 114 outputs a communication packet of content request information to the control unit 112. The destination virtual private IP address is set to “192.168.0.12”, and the source virtual private IP address is set to “192.168.0.11” (step S26.1). : Packet (192.168.0.12, 192.168.0.11)).

  The control unit 112 refers to the client terminal virtual address information 574-2 in the relay server information 57 stored in the relay server information storage unit 117, so that the transmission destination is not the LAN 1 but the LAN 2 via the WAN 3. Confirm.

  The client terminal 11 is set to “Transaction: c1” in the connection for IP communication using the virtual address established in step S15 and set to “groupID=20070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content request information is output to the socket of the own device. The client terminal 11 transmits a communication packet of content request information to the relay server 12 (step S26.1.1: connection (packet)).

  The relay server 12 receives a communication packet from the client terminal 11. The control unit 122 refers to the client terminal virtual address information 574-2 in the relay server information 57 stored in the relay server information storage unit 125, so that the transmission destination is not in LAN1 but in LAN2 via WAN3. Confirm.

  The relay server 12 is set to “Transaction: s1” in the connection for IP communication using the virtual address established in step S6 and set to “groupID=20070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content request information is output to the socket of the own device. The relay server 12 transmits a communication packet of content request information to the relay server 22 (step S26.1.1.1: connection (packet)).

  The relay server 22 receives a communication packet from the relay server 12. The control unit 222 refers to the client terminal virtual address information 574-2 in the relay server information 57 stored in the relay server information storage unit 225, so that the transmission destination is not in the LAN 1 via the WAN 3 but in the LAN 2. Confirm.

  The relay server 22 is set to “Transaction: c2” in the connection for IP communication using the virtual address established in step S19 and set to “groupID=2070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content request information is output to the socket of the own device. The relay server 22 transmits a communication packet of content request information to the client terminal 21 (step S26.1.1.1.1: connection (packet)).

  The client terminal 21 receives a communication packet from the relay server 22. The control unit 212 outputs a communication packet of the content request information to the virtual LAN driver 214 (Step S26.1.1.1.1.1.1: packet (192.168.0.12, 192.168 .. 0.11)).

  The virtual LAN driver 214 outputs the content request information whose virtual private IP address of the transmission source is “192.168.0.11” to the web server 213 (step S26.1.1.1.1). 1.1: http (192.168.0.11)). The content request is completed by the above processing flow.

[Processing flow of step S27]
The web server 213 outputs the content whose destination virtual private IP address is “192.168.0.11” to the virtual LAN driver 214 (step S27: http (192.168.0.11). )).

  The virtual LAN driver 214 outputs a content communication packet to the control unit 212. The destination virtual private IP address is set to “192.168.0.11”, and the source virtual private IP address is set to “192.168.0.12” (step S27.1). : Packet (192.168.0.11, 192.168.0.12)).

  The control unit 212 refers to the client terminal virtual address information 574-1 among the relay server information 57 stored in the relay server information storage unit 217, so that the transmission destination is not in the LAN 2 but in the LAN 1 via the WAN 3. Confirm.

  The client terminal 21 is set to “Transaction: c2” in the connection for IP communication using the virtual address established in step S19 and set to “groupID=20070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content is output to the socket of the own device. The client terminal 21 transmits a content communication packet to the relay server 22 (step S27.1.1: connection (packet)).

  The relay server 22 receives a communication packet from the client terminal 21. The control unit 222 refers to the client terminal virtual address information 574-1 among the relay server information 57 stored in the relay server information storage unit 225, so that the transmission destination is not in the LAN 2 but in the LAN 1 through the WAN 3. Confirm.

  The relay server 22 is set to “Transaction: s2” in the connection for IP communication using the virtual address established in step S6 and set to “groupID=2070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content is output to the socket of the own device. The relay server 22 transmits a content communication packet to the relay server 12 (step S27.1.1.1.1: connection (packet)).

  The relay server 12 receives a communication packet from the relay server 22. The control unit 122 refers to the client terminal virtual address information 574-1 in the relay server information 57 stored in the relay server information storage unit 125, so that the transmission destination is not in the LAN 2 via the WAN 3 but in the LAN 1. Confirm.

  The relay server 12 is set to “Transaction: c1” in the IP communication connection using the virtual address established in step S15 and set to “groupID=20070402133100@relay-server-1.abc.net”. The communication packet of the encapsulated content is output to the socket of the own device. The relay server 12 transmits a content communication packet to the client terminal 11 (step S27.1.1.1.1: connection (packet)).

  The client terminal 11 receives a communication packet from the relay server 12. The control unit 112 outputs a content communication packet to the virtual LAN driver 114 (step S27.1.1.1.1.1.1: packet (192.168.0.11, 192.168.8.0. 12)).

  The virtual LAN driver 114 outputs the content whose source virtual private IP address is “192.168.0.12” to the web browser 113 (step S27.1.1.1.1.1). .1: http (192.168.0.12)). With the above processing flow, the provision of content ends.

{Summary of data transmission and reception}
Each device constituting the relay communication system is assigned a virtual private IP address, and establishes a connection for IP communication using the virtual address between them. Each device that configures the relay communication system shares in real time information regarding the connection establishment for IP communication using the virtual private IP address of all devices and the virtual address of all devices in response to changes in the state of the relay communication system. is doing.

  The data transmission side transmits data in which the virtual private IP address of the data reception side is designated as the transmission destination. The data reception side receives data in which the virtual private IP address of the data transmission side is designated as the transmission source. A communication packet of transmission data is encapsulated in a WAN interposed between remote LANs.

  Each device involved in data transmission / reception checks the data receiving side's virtual private IP address against the relay server virtual address information or the client terminal virtual address information to determine which device the communication packet of the transmission data is transferred to. decide. Each device involved in data transmission / reception refers to the connection establishment information for IP communication using a virtual address, and determines which connection socket to output a communication packet of transmission data to.

  In the prior art VPN, each device is assigned a virtual private IP address. However, each device does not share information about virtual private IP addresses of all devices, and also does not share information about connection establishment of all devices. Therefore, when a communication error occurs when each device transmits data, it is unclear whether the virtual private IP address specified as the destination does not exist or whether the device specified as the destination has not established a connection. There was a clear problem.

  In the relay communication system of the present invention, each device is assigned a virtual private IP address. Further, each device shares information about the virtual private IP address of all devices, and also shares information about connection establishment of all devices. Therefore, it is possible to solve the problems in the prior art VPN and to construct a virtual network with expandability and flexibility in response to a change in the state of the relay communication system.

It is a figure which shows the whole structure of a relay communication system. It is a figure which shows the component of a relay server. It is a figure which shows the component of a client terminal. It is a figure which shows the specific example of relay group information. It is a figure which shows the specific example of relay server information. It is a figure which shows the specific example of client terminal information. It is a figure which shows the flow of information sharing. It is a figure which shows the flow of information sharing. It is a figure which shows the flow of information sharing. It is a figure which shows the information stored after step S2. It is a figure which shows the relay group map displayed after step S2. It is a figure which shows the information stored after step S4. It is a figure which shows the relay group map displayed after step S4. It is a figure which shows the information stored after step S6. It is a figure which shows the relay group map displayed after step S6. It is a figure which shows the information stored after step S9. It is a figure which shows the relay group map displayed after step S9. It is a figure which shows the information stored after step S13. It is a figure which shows the relay group map displayed after step S13. It is a figure which shows the information stored after step S17. It is a figure which shows the relay group map displayed after step S17. It is a figure which shows the information stored after step S21. It is a figure which shows the relay group map displayed after step S21. It is a figure which shows the flow of data transmission / reception.

Explanation of symbols

1, 2 LAN
3 WAN
11, 21 Client terminal 12, 22 Relay server 31 SIP server 111, 211 Interface unit 112, 212 Control unit 113 Web browser 213 Web server 114, 214 Virtual LAN driver 115, 215 Database storage unit 116, 216 Relay group information storage unit 117 217 Relay server information storage unit 118, 218 Relay group map display unit 121, 221 Interface unit 122, 222 Control unit 123, 223 Database storage unit 124, 224 Relay group information storage unit 125, 225 Relay server information storage unit 126, 226 Client terminal information storage unit 127, 227 Relay group map display unit 128, 228 Virtual LAN driver

Claims (4)

A first network, a second network,
A first relay server connected to the first network;
A second relay server connected to the second network;
A relay communication system comprising:
The first relay server and the second relay server are:
A relay group information creating unit for creating relay group information indicating a relay group constituted by the first relay server and the second relay server and a virtual network address used in the relay group;
Including
The first relay server is
The first relay server includes first relay server activation information indicating an activation state of the first relay server, and a connection state between the first relay server and a first client terminal connected to the first network. A first relay server information creating unit that creates first relay server information including first client terminal registration information relating to the registered first client terminal;
Including
The second relay server is
The second relay server includes the second relay server activation information indicating the activation state of the second relay server and the connection state between the second relay server and the second client terminal connected to the second network. A second relay server information creating unit that creates second relay server information including second client terminal registration information related to the registered second client terminal;
Including
The first relay server and the second relay server are:
Inter-relay server sharing in which the relay server information including the first relay server information and the second relay server information and the relay group information are shared between the first relay server and the second relay server. And
A virtual network address managed to be unique within the relay group is dynamically assigned to the first client terminal and the second client terminal at a predetermined timing, and information on the assigned virtual network address is provided to the relay server. A virtual address management unit to be registered in the information;
Including
The first relay server is
A first inter-client-terminal sharing unit that shares the relay group information and the relay server information between the first relay server and the first client terminal;
Including
The second relay server is
A second inter-client-terminal sharing unit that shares the relay group information and the relay server information between the second relay server and the second client terminal;
A relay communication system comprising: The relay communication system according to claim 1,
The relay group information is
Relay server connection establishment information as to whether the first relay server and the second relay server have established a connection;
Including
The first relay server information is
First client terminal connection establishment information as to whether or not the first client terminal has established a connection with the first relay server;
Including
The second relay server information is
Second client terminal connection establishment information as to whether the second client terminal has established a connection with the second relay server;
A relay communication system comprising: In the relay communication system according to claim 1 or 2,
The first relay server is
Communication relayed by the first relay server, in which the virtual network address of the second network selected based on the relay group information and the relay server information is designated as a communication destination, the relay group information and the relay A communication execution unit to be executed based on the server information,
A relay communication system comprising: The relay communication system according to any one of claims 1 to 3,
The first relay server and the first client terminal are:
Based on the relay group information and the relay server information, a map display unit that displays a map that visually represents a connection establishment status and a virtual address in the current relay group;
A relay communication system comprising:

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