PROXY SERVER, COMMUNICATION SYSTEM, COMMUNICATION METHOD AND PROGRAM

• US 20100074100A1
• Filed: 10/19/2007
• Published: 03/25/2010
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kazami, Hiroshi, Suzuki, Motohiro
• Granted Patent: US 8,374,079 B2
• Time in Patent Office: Days
• US Class Current: 370/221
• CPC Class Codes: G06F 11/2025 using centralised failover control functionality
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/203 using migration
• CPC Class Codes: G06F 11/2038 with a single idle spare processing component

Abstract

A proxy server in an SIP network includes the common SIP proxy server function 11, the function of determining whether an SIP request and an SIP response received by the proxy server 10 belong to a call flow encountering a failure of the working SIP server 30, and the function of, when determination is made that they belong to a call flow encountering a failure, referring to the contents of the received SIP request and SIP response to specify a destination to which the SIP request and the SIP response are to be transmitted next.

Claims

1. A proxy server comprising:

an SIP proxy server function of intervening an SIP message transmitted and received between a user terminal, and a working SIP (Session Initiation Protocol) server and a spare SIP server;

a message kind determination function of determining a kind of received message;

a transfer destination failure detection function of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination function of determining, based on a notification from said transfer destination failure detection function, whether a message received by said proxy server function belongs to a call flow encountering a failure of said working SIP server or not; and

a destination setting function of setting, based on a notification from said transfer destination failure detection function and according to a failure occurrence situation of said working SIP server and a kind of message received by said proxy server function, a transfer destination of the message.

3. The proxy server according to claim 1, wherein said destination setting function comprises a function of holding, as information, a standard transfer destination which is updated by a notification of failure occurrence on said working SIP server notified by said transfer destination failure detection function and to which a message is to be transferred unless otherwise designated.

4. The proxy server according to claim 1, wherein said transfer destination failure detection function comprises a function of monitoring a REGISTER request and an SIP response transmitted and received between said working SIP server and said user terminal and when failing to detect an SIP response from said working SIP server, determining that said working SIP server develops a fault.

5. The proxy server according to claim 1, wherein said call failure encounter determination function comprises a function of using a call identifier list which holds a call identifier stored in said SIP message externally received and is once erased all at the detection of failure occurrence on said working SIP server to determine that said message holding a call identifier not recited in the call identifier list encounters a failure of said working SIP server.

6. The proxy server according to claim 1, wherein said destination determination function comprises a function of extracting an address recited next to said working SIP server from information related to a transfer path of a message which is stored in said message and considering the address as a subsequent transfer destination in order to directly transfer the message to the address.

7. The proxy server according to claim 1, wherein said destination determination function comprises a function of cooperating with an external system while ignoring information related to a transfer path which is stored in said message to execute address solution of a destination based on destination information of said message.

2. A proxy server comprising:

a proxy server function of intervening an SIP message transmitted and received between a user terminal, and a working SIP server and a spare SIP server;

a message kind determination function of determining a kind of received message;

a transfer destination failure detection function of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination function of determining, based on a notification from said transfer destination failure detection function, whether a message received by said proxy server function belongs to a call flow encountering a failure of said working SIP server or not;

a destination setting function of setting, based on a notification from said transfer destination failure detection function and according to a failure occurrence situation of said working SIP server and a kind of message received by said proxy server function, a transfer destination of the message; and

a re-transmission request generating function of generating a re-transmission request to be transferred to said user terminal in order to urge said user terminal to re-transfer an initial INVITE request.

8. The proxy server according to claim 2, wherein said re-transmission request generation function comprises a function of generating an SIP response which induces said user terminal to transmit a message again after a lapse of a predetermined time period according to processing to be executed at the time of ordinary SIP response reception.

9. A proxy server, comprising a function of, after receiving an external message, examining a kind of message and when the received message is an SIP request, further examining whether the received message belongs to a call flow encountering a failure of a working SIP server or not, and when the determination is made that the received message belongs to a call flow encountering a failure of said working SIP server, referring to the contents of the message to newly determine a transfer destination of the message.

11. A proxy server according to claim 9, further comprising a function of, when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure, and when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to a user terminal in order to urge said user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

10. A proxy server, comprising a function of, after receiving an external message, examining a kind of message and when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure, and when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to a user terminal in order to urge said user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

12. A communication system including working and spare SIP servers which transmit and receive an SIP message to/from a user terminal, and a proxy server which intervenes transmission/reception of said SIP message, wherein said proxy server comprising:

an SIP proxy server function of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination function of determining a kind of received message;

a transfer destination failure detection function of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination function of determining, based on a notification from said transfer destination failure detection function, whether a message received by said proxy server function belongs to a call flow encountering a failure of said working SIP server or not; and

a destination setting function of setting, based on a notification from said transfer destination failure detection function and according to a failure occurrence situation of said working SIP server and a kind of message received by said proxy server function, a transfer destination of the message.

14. The communication system according to claim 12, wherein said destination setting function of said proxy server comprises a function of holding, as information, a standard transfer destination which is updated by a notification of failure occurrence on said working SIP server notified by said transfer destination failure detection function and to which a message is to be transferred unless otherwise designated.

15. The communication system according to claim 12, wherein said transfer destination failure detection function of said proxy server comprises a function of monitoring a REGISTER request and an SIP response transmitted and received between said working SIP server and said user terminal and when failing to detect an SIP response from said working SIP server, determining that said working SIP server develops a fault.

16. The communication system according to claim 12, wherein said call failure encounter determination function of said proxy server comprises a function of using a call identifier list which holds a call identifier stored in said SIP message externally received and is once erased all at the detection of failure occurrence on said working SIP server to determine that said message holding a call identifier not recited in the call identifier list encounters a failure of said working SIP server.

17. The communication system according to claim 12, wherein said destination determination function of said proxy server comprises a function of extracting an address recited next to said working SIP server from information related to a transfer path of a message which is stored in said message and considering the address as a subsequent transfer destination in order to directly transfer the message to the address.

18. The communication system according to claim 12, wherein said destination determination function of said proxy server comprises a function of cooperating with an external system while ignoring information related to a transfer path which is stored in said message to execute address solution of a destination based on destination information of said message.

13. A communication system including working and spare SIP servers which transmit and receive an SIP message to/from a user terminal, and a proxy server which intervenes transmission/reception of said SIP message, wherein said proxy server comprising:

a proxy server function of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination function of determining a kind of received message;

a transfer destination failure detection function of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination function of determining, based on a notification from said transfer destination failure detection function, whether a message received by said proxy server function belongs to a call flow encountering a failure of said working SIP server or not;

a destination setting function of setting, based on a notification from said transfer destination failure detection function and according to a failure occurrence situation of said working SIP server and a kind of message received by said proxy server function, a transfer destination of the message; and

a re-transmission request generating function of generating a re-transmission request to be transferred to said user terminal in order to urge said user terminal to re-transfer an initial INVITE request.

19. The communication system according to claim 13, wherein said re-transmission request generation function of said proxy server comprises a function of generating an SIP response which induces said user terminal to transmit a message again after a lapse of a predetermined time period according to processing to be executed at the time of ordinary SIP response reception.

20. A communication system including working and spare SIP servers which transmit and receive an SIP message to/from a user terminal, and a proxy server which intervenes transmission/reception of said SIP message, wherein said proxy server comprising:

a function of, after receiving an external message, examining a kind of message and when the received message is an SIP request, further examining whether the received message belongs to a call flow encountering a failure of the working SIP server or not, and when the determination is made that the received message belongs to a call flow encountering a failure of said working SIP server, referring to the contents of the message to newly determine a transfer destination of the message.

22. A communication system comprising the functions according to claim 20, wherein said proxy server further comprising a function of, when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure, and when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

21. A communication system including working and spare SIP servers which transmit and receive an SIP message to/from a user terminal, and a proxy server which intervenes transmission/reception of said SIP message, wherein said proxy server comprising:

a function of, after receiving an external message, examining a kind of message and when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure, and when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

23. A communication method at a proxy server which, for working and spare SIP servers that transmit and receive an SIP message to/from an external user terminal, intervenes transmission/reception of said SIP message, comprising:

an intervening step of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination step of determining a kind of message received at said intervening step;

a transfer destination failure detection step of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination step of receiving a notification from said transfer destination failure detection step to determine whether a message received at said intervening step belongs to a call flow encountering a failure of said working SIP server or not; and

a destination setting step of receiving a notification from said transfer destination failure detection step to set a transfer destination of a message according to a failure occurrence situation of said working SIP server and a kind of message received at said intervening step.

25. The communication method according to claim 23, wherein said destination setting step includes a step of holding, as information, a standard transfer destination which is updated by a notification of failure occurrence on said working SIP server notified by said transfer destination failure detection step and to which a message is to be transferred unless otherwise designated.

26. The communication method according to claim 23, wherein said transfer destination failure detection step includes a step of monitoring a REGISTER request and an SIP response transmitted and received between said working SIP server and said user terminal and when failing to detect an SIP response from said working SIP server, determining that said working SIP server develops a fault.

27. The communication method according to claim 23, wherein said call failure encounter determination step includes a step of using a call identifier list which holds a call identifier stored in said SIP message externally received and is once erased all at the detection of failure occurrence on said working SIP server to determine that said message holding a call identifier not recited in the call identifier list encounters a failure of said working SIP server.

28. The communication method according to claim 23, wherein said destination determination step includes a step of extracting an address recited next to said working SIP server from information related to a transfer path of a message which is stored in said message and considering the address as a subsequent transfer destination in order to directly transfer the message to the address.

29. The communication method according to claim 23, wherein said destination determination step includes a step of cooperating with an external system while ignoring information related to a transfer path which is stored in said message to execute address solution of a destination based on destination information of said message.

24. A communication method at a proxy server which, for working and spare SIP servers that transmit and receive an SIP message to/from an external user terminal, intervenes transmission/reception of said SIP message, comprising:

an intervening step of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination function of determining a kind of message received at said intervening step;

a transfer destination failure detection step of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination step of receiving a notification from said transfer destination failure detection step to determine whether a message received at said intervening step belongs to a call flow encountering a failure of said working SIP server or not;

a destination setting step of receiving a notification from said transfer destination failure detection step to set a transfer destination of the message according to a failure occurrence situation of said working SIP server and a kind of message received at said intervening step; and

a re-transmission request generating step of generating a re-transmission request to be transferred to said user terminal in order to urge said user terminal to re-transfer an initial INVITE request.

30. The communication method according to claim 24, wherein said re-transmission request generation step includes a step of generating an SIP response which induces said user terminal to transmit a message again after a lapse of a predetermined time period according to processing to be executed at the time of ordinary SIP response reception.

31. A communication method at a proxy server which, for working and spare SIP servers that transmit and receive an SIP message to/from an external user terminal, intervenes transmission/reception of said SIP message, comprising:

a step of, after receiving an external message, examining a kind of message and when the received message is an SIP request, further examining whether the received message belongs to a call flow encountering a failure of the working SIP server or not; and

a step of, when the determination is made that a received message belongs to a call flow encountering a failure of said working SIP server, referring to the contents of the message to newly determine a transfer destination of the message.

33. The communication method according to claim 31, further comprising:

a step of, when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure; and

a step of, when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

32. A communication method at a proxy server which, for working and spare SIP servers that transmit and receive an SIP message to/from an external user terminal, intervenes transmission/reception of said SIP message, comprising:

a step of, after receiving an external message, examining a kind of message;

a step of, when the received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure; and

a step of, when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

34. A computer readable medium storing a program executed on a proxy server which intervenes transmission/reception of a message, with respect to working and spare communication control devices which transmit and receive said message to/from an external user terminal, comprising:

an intervening processing of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination processing of determining a kind of message received at said intervening processing;

a transfer destination failure detection processing of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination processing of receiving a notification from said transfer destination failure detection processing to determine whether a message received at said intervening processing belongs to a call flow encountering a failure of said working SIP server or not; and

a destination setting processing of receiving a notification from said transfer destination failure detection processing to set a transfer destination of a message according to a failure occurrence situation of said working SIP server and a kind of message received at said intervening processing.

36. The computer readable medium storing the program according to claim 34, wherein said destination setting processing includes a processing of holding, as information, a standard transfer destination which is updated by a notification of failure occurrence on said working SIP server notified by said transfer destination failure detection processing and to which a message is to be transferred unless otherwise designated.

37. The computer readable medium storing the program according to claim 34, wherein said transfer destination failure detection processing includes a processing of monitoring a REGISTER request and an SIP response transmitted and received between said working SIP server and said user terminal and when failing to detect an SIP response from said working SIP server, determining that said working SIP server develops a fault.

38. The computer readable medium storing the program according to claim 34, wherein said call failure encounter determination processing includes a processing of using a call identifier list which holds a call identifier stored in said SIP message externally received and is once erased all at the detection of failure occurrence on said working SIP server to determine that said message holding a call identifier not recited in the call identifier list encounters a failure of said working SIP server.

39. The computer readable medium storing the program according to claim 34, wherein said destination determination processing includes a processing of extracting an address recited next to said working SIP server from information related to a transfer path of a message which is stored in said message and considering the address as a subsequent transfer destination in order to directly transfer the message to the address.

40. The computer readable medium storing the program according to claim 34, wherein said destination determination processing includes a processing of cooperating with an external system while ignoring information related to a transfer path which is stored in said message to execute address solution of a destination based on destination information of said message.

35. A computer readable medium storing a program executed on a proxy server which intervenes transmission/reception of a message, with respect to working and spare communication control devices which transmit and receive said message to/from an external user terminal, comprising:

an intervening processing of intervening an SIP message transmitted and received between the user terminal, and the working SIP server and the spare SIP server;

a message kind determination processing of determining a kind of message received at said intervening processing;

a transfer destination failure detection processing of detecting and notifying a failure occurring on said working SIP server;

a call failure encounter determination processing of receiving a notification from said transfer destination failure detection step to determine whether a message received at said intervening processing belongs to a call flow encountering a failure of said working SIP server or not;

a destination setting processing of receiving a notification from said transfer destination failure detection processing to set a transfer destination of a message according to a failure occurrence situation of said working SIP server and a kind of message received by said intervening processing; and

a re-transmission request generating processing of generating a re-transmission request to be transferred to said user terminal in order to urge said user terminal to re-transfer an initial INVITE request.

41. The computer readable medium storing the program according to claim 35, wherein said re-transmission request generation processing includes a processing of generating an SIP response which induces said user terminal to transmit a message again after a lapse of a predetermined time period according to processing to be executed at the time of ordinary SIP response reception.

42. A computer readable medium storing a program executed on a proxy server which intervenes transmission/reception of a message, with respect to working and spare communication control devices which transmit and receive said message to/from an external user terminal, comprising:

a processing of, after receiving an external message, examining a kind of message and when the received message is an SIP request, further examining whether the received message belongs to a call flow encountering a failure of the working SIP server or not; and

a processing of, when the determination is made that a received message belongs to a call flow encountering a failure of said working SIP server, referring to the contents of the message to newly determine a transfer destination of the message.

44. The computer readable medium storing the program according to claim 42, further comprising:

a processing of, when a received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure; and

a processing of, when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.

43. A computer readable medium storing a program executed on a proxy server which intervenes transmission/reception of a message, with respect to working and spare communication control devices which transmit and receive said message to/from an external user terminal, comprising:

a processing of, after receiving an external message, examining a kind of message;

a processing of, when a received message is an authentication INVITE request, further examining whether the request belongs to a call flow encountering a failure; and

a processing of, when the request belongs to a call flow encountering a failure, generating a re-transmission request to be transferred to said user terminal in order to urge the user terminal to re-transfer an initial INVITE request again and transferring the request to said user terminal.