System and method for sharing a SIP communication service identifier

1. A method for indicating an application server (AS) capability, the method comprising:

generating, at the AS, a Session Initiation Protocol (SIP) request including a SIP header comprising a token that identifies at least one service supported by the AS that is included in the signaling route and the SIP request further including a uniform resource identifier (URI) comprising an address of the AS;

transmitting, by the AS, the SIP request via the communication network towards a first user agent (UA); and

transmitting, by the AS, a SIP response via the communication network to a second user agent (UA), the SIP response including the token.

2. The method of claim 1 wherein the URI is a Globally Routable UA URI (GRUU).

3. The method of claim 1 wherein the token indicates whether the at least one service is provided by the AS as an originating AS or a terminating AS.

4. The method of claim 1 wherein the token is an IP (Internet Protocol) Multimedia Subsystem (IMS) Communication Service Identifier (ICSI).

5. The method of claim 4 wherein a URI parameter in the URI is set equal to an ICSI value for a particular service provided by the AS.

6. The method of claim 5 wherein the URI parameter is a g. 3 gpp.app_ref tag.

7. The method of claim 1 wherein the URI is included in one of:

a Record-Route header;

a Record header;

a Via header; and

a Contact address.

8. The method of claim 1 wherein the first SIP request that the AS receives from the first UA is a SIP INVITE message.

9. The method of claim 1 wherein the token is associated with the at least one service by one of:

a hard coding of the association; and

execution of an algorithm that performs the association.

10. A network component comprising a processor configured to:

generate, at the network component, a Session Initiation Protocol (SIP) request including a SIP header comprising a token that identifies at least one service supported by the network component, the SIP request further including a uniform resource identifier (URI) comprising an address of the network component;

transmit by the network component, the SIP request via the communication network towards a first user agent (UA); and

transmit, by the network component, a SIP response via the communication network to a second user agent (UA) different than the first UA, the SIP response including the token.

11. The network component of claim 10 wherein the URI is a Globally Routable UA URI (GRUU).

12. The network component of claim 10 wherein the URI contains a ‘gr’ parameter.

13. The network component of claim 10 wherein the token is an IP (Internet Protocol) Multimedia Subsystem (IMS) Communication Service Identifier (ICSI).

14. The network component of claim 13 wherein a URI parameter in the URI is set equal to the ICSI.

15. The network component of claim 14 wherein the URI parameter is a g. 3 gpp.app_ref tag.

16. The network component of claim 10 wherein the URI is included in one of: a Record-Route header;

a Record header;

a Via header; and

a Contact address.

17. The network component of claim 16 , further comprising receiving, by the network component, a SIP invite from the second UA before the network component generates the SIP request.

18. The network component of claim 17 wherein a user portion of the URI identifies at least one of:

a user agent that originated the SIP INVITE message; and a

user agent that terminates the SIP INVITE message.

19. The network component of claim 17 wherein the AS is a telephony application server.

20. The network component of claim 10 wherein the token is associated with the at least one service by one of:

a hard coding of the association; and

execution of an algorithm that performs the association.