Method and apparatus for supporting communications between a computing device within a network and an external computing device

• US 20040024879A1
• Filed: 07/30/2002
• Published: 02/05/2004
• Est. Priority Date: 07/30/2002
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Incorporated
• Inventors: Dingman, Christopher P., Mahadevan, Priya, Ordille, Joann J.
• Granted Patent: US 9,497,168 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• CPC Class Codes: H04L 63/0281 Proxies
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066

Abstract

A network communication bridge establishes communication between a computing system within a protected network and an external computing system. A registrar is positioned outside the protected network and registers authorized users. The registrar determines if the computing device associated with the user is publicly addressable, and for those computing devices that are not publicly addressable, the computing device maintains a persistent communication session with a bridge proxy server. The bridge proxy server employs a reversal or relaying technique to enable communication between two systems that cannot ordinarily establish communication with each other, based on characteristics of the two systems. If at least one party to a communication is publicly addressable, then a reversal technique is employed. If neither party to the communication is publicly addressable, then both parties have a persistent session with their respective bridge proxy server, and the bridge proxy server acts as a “relay service” for communications between the initiator and the recipient. The invention can be implemented as a separate application or as an enhancement to the Session Initiation Protocol (SIP).

Claims

1. A method for determining whether a first computing system within a protected network can communicate with an external computing system, said method comprising the steps of:

receiving a registration request from at least one of said first and external computing systems; and

determining whether said computing system is publicly addressable.

2. The method of claim 1, wherein said determining step further comprises the step of comparing address information indicated by said computing system with address information indicated in a message received from said computing system.

3. The method of claim 1, wherein said determining step further comprises the step of attempting to connect with said computing system.

4. The method of claim 1, further comprising the step of recording an address of said computing system if said computing system is publicly addressable.

5. The method of claim 1, further comprising the step of initiating a creation of a persistent connection between said computing system and a proxy server if said computing system is not publicly addressable.

6. The method of claim 5, further comprising the step of recording an address of said proxy server for said computing system if said computing system is not publicly addressable.

7. The method of claim 5, further comprising the step of initiating a reversal of roles between a call initiator and a call recipient if at least one party to a communication is publicly addressable.

8. The method of claim 5, further comprising the step of providing a relay service between parties to a communication if neither party is publicly addressable.

9. The method of claim 1, wherein said registration request conforms to the SIP protocol.

10. The method of claim 1, wherein said determining step is performed by a SIP registrar.

11. The method of claim 8, wherein said relay service is performed by a SIP proxy server.

12. The method of claim 1, further comprising the step of propagating results of said determining step to one or more additional computing systems.

13. The method of claim 12, wherein said one or more additional computing systems are within the same sub-network as said computing system providing said registration request.

14. A system for determining whether a first computing system within a protected network can communicate with an external computing system, said system comprising:

a memory that stores computer-readable code; and

a processor operatively coupled to said memory, said processor configured to implement said computer-readable code, said computer-readable code configured to;

receive a registration request from at least one of said first and external computing systems; and

determine whether said computing system is publicly addressable.

15. The system of claim 14, wherein said processor is further configured to compare address information indicated by said computing system with address information indicated in a message received from said computing system.

16. The system of claim 14, wherein said processor is further configured to attempt to connect with said computing system.

17. The system of claim 14, wherein said processor is further configured to record an address of said computing system if said computing system is publicly addressable.

18. The system of claim 14, wherein said processor is further configured to initiate a creation of a persistent connection between said computing system and a proxy server if said computing system is not publicly addressable.

19. The system of claim 18, wherein said processor is further configured to record an address of said proxy server for said computing system if said computing system is not publicly addressable.

20. The system of claim 18, wherein said processor is further configured to initiate a reversal of roles between a call initiator and a call recipient if at least one party to a communication is publicly addressable.

21. The system of claim 18, wherein said processor is further configured to provide a relay service between parties to a communication if neither party is publicly addressable.

22. The system of claim 14, wherein said registration request conforms to the SIP protocol.

23. The system of claim 14, wherein said determining step is performed by a SIP registrar.

24. The system of claim 21, wherein said relay service is performed by a SIP proxy server.

25. An article of manufacture for determining whether a first computing system within a protected network can communicate with an external computing system, said article of manufacture comprising:

a computer readable medium having computer readable code means embodied thereon, said computer readable program code means comprising;

a step to receive a registration request from at least one of said first and external computing systems; and

a step to determine whether said computing system is publicly addressable.

26. A method for enabling a first computing system within a protected network to communicate with an external computing system, said method comprising the steps of:

determining whether at least one of said first and external computing systems is publicly addressable; and

initiating a reversal of roles as a call initiator and a call recipient for a communication between said first and external computing systems if at least one of said first and external computing systems is publicly addressable.

27. A system for enabling a first computing system within a protected network to communicate with an external computing system, said system comprising:

a memory that stores computer-readable code; and

a processor operatively coupled to said memory, said processor configured to implement said computer-readable code, said computer-readable code configured to;

determine whether at least one of said first and external computing systems is publicly addressable; and

initiate a reversal of roles as a call initiator and a call recipient for a communication between said first and external computing systems if at least one of said first and external computing systems is publicly addressable.

28. A method for determining whether a first computing system within a protected network can communicate with an external computing system, said method comprising the steps of:

determining whether at least one of said first and external computing systems is publicly addressable; and

propagating results of said determining step to one or more additional computing systems.

29. The method of claim 28, wherein said one or more additional computing systems are within the same sub-network as said at least one of said first and external computing systems.