Message Handling in an IP Multimedia Subsystem

• US 20100299442A1
• Filed: 01/11/2008
• Published: 11/25/2010
• Est. Priority Date: 01/11/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: van Elburg, Johannes
• Granted Patent: US 8,762,553 B2
• Time in Patent Office: Days
• US Class Current: 709/229
• CPC Class Codes: H04L 49/25 Routing or path finding in a switch fabric
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/147 Signalling methods or messages providing extensions to protocols defined by standardisation
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

A method and apparatus for handling a Session Initiation Protocol communication in an IP Multimedia Subsystem (IMS) network. A Proxy Call Session Control Function (3) receives a Session Initiation Protocol message sent from a trusted remote network. The P-CSCF (3) adds to the message a further header, which identifies a Public User Identity of a trusted entity located in the remote network served by a Serving Call Session Control Function (7) in the IMS network. The message is then sent to the S-CSCF (7). The S-CSCF (7), and any other node that the message is sent to, knows from the presence of the furtherheader to use the Public User Identity of the trusted entity to determine the served user rather than the P-Asserted Identity contained in the SIP message.

Claims

1-11. -11. (canceled)

12. A method of handling a Session Initiation Protocol communication within an IP Multimedia Subsystem network, the method comprising:

at a Proxy Call Session Control Function, receiving a Session Initiation Protocol message sent from a trusted entity located in a remote network, wherein the Session Initiation Protocol message originated from a further entity whose identity has been asserted by the trusted entity;

at the Proxy Call Session Control Function, determining that the identity of the trusted entity does not match an identity contained in a P-Asserted-Identity of the message;

in the event of such a determination, at the Proxy Call Session Control Function, adding to the Session Initiation Protocol message a further header, the further header identifying a Public User Identity of a trusted entity in the remote network served by a Serving Call Session Control Function; and

sending the message to the Serving Call Session Control Function.

13. The method of claim 12, further comprising obtaining the Public User Identity of the trusted entity by determining the identity of a secure channel on which the Session Initiation Protocol message was received.

14. The method of claim 12, further comprising;

at the Serving Call Session Control Function, identifying the presence of the further header and using the Public User Identity of the trusted entity to determine the served user instead of the P-Asserted-Identity.

15. The method of claim 12, wherein the Session Initiation Protocol message sent from a remote network is sent via a business trunk.

16. The method of claim 12, wherein the further header identifying the Public User Identity is obtained from subscription information relating to the trusted entity'"'"'s Public User Identity stored at one of a Home Subscriber Server and a User Profile Server Function located in the IP Multimedia Subsystem network.

17. The method of claim 16, wherein the subscription information relating to the trusted entity'"'"'s Public User Identity includes an Implicit Registration Set, the Implicit Registration Set comprising a wildcarded Public User Identity or Public User Identity sub-domain representative of a range of Public User Identities.

18. The method of claim 12, wherein the Session Initiation Protocol message is a Session Initiation Protocol INVITE message.

19. A Proxy Call Session Control Function node for use in an IP Multimedia Subsystem network, the Proxy Call Session Control Function node comprising:

a receiver configured to receive a Session Initiation Protocol message sent from a trusted entity located in a remote network, wherein the Session Initiation Protocol message originated from a further entity whose identity has been asserted by the trusted entity;

a processor configured to receive subscription information relating to the trusted entity Public User Identity from one of a Home Subscriber Server and a User Profile Server Function located in the IP Multimedia Subsystem network, determine that the identity of the trusted entity does not match an identity contained in a P-Asserted-Identity of the message, and, in the event of such a determination, add to the message a further header, the further header identifying a Public User Identity of a trusted entity in the remote network served by a Serving Call Session Control Function; and

a transmitter configured to send the message to the Serving Call Session Control Function.

20. The Proxy Call Session Control Function node of claim 19, wherein the subscription information relating to the trusted entity Public User Identity includes an Implicit Registration Set, the Implicit Registration Set comprising a wildcarded Public User Identity or Public User Identity sub-domain representative of a range of Public User Identities.

21. A Serving Call Session Control Function node for use in an IP Multimedia Subsystem network, the Serving Call Session Control Function node comprising:

a receiver configured to receive a Session Initiation Protocol message from a Proxy Call Session Control Function node, the Session Initiation Protocol message originating from a user in a remote network and having been sent by to the Proxy Call Session Control Function node via a trusted entity in the remote network;

a processor configured to identify the presence of a further header in the Session Initiation Protocol message, the further header identifying a Public User Identity of the trusted entity in the remote network served by the Serving Call Session Control Function, wherein the processor is further configured to, in the event that the further header is identified, use the Public User Identity of the trusted entity as the served user instead of the P-Asserted-Identity.

22. An Application Server for use in an IP Multimedia Subsystem network, the Application Server comprising:

a receiver configured to receive a Session Initiation Protocol message, the Session Initiation Protocol message originating from a user in a remote network and having been sent to a Proxy Call Session Control Function node via a trusted entity in the remote network;

a processor configured to identify the presence of a further header in the Session Initiation Protocol message, the further header identifying a Public User Identity of the trusted entity in the remote network served by a Serving Call Session Control Function in the IP Multimedia Subsystem network, wherein the processor is further configured to, in the event that the further header is identified, use the Public User Identity of the trusted entity as the served user instead of the P-Asserted-Identity.