Methods, systems, and computer program products for clustering and communicating between Internet protocol multimedia subsystem (IMS) entities

• US 20060136557A1
• Filed: 12/16/2005
• Published: 06/22/2006
• Est. Priority Date: 12/17/2004
• Status: Active Grant

• Current Assignee: Tekelec, Inc. (Oracle Corporation)
• Original Assignee: Tekelec
• Inventors: Marsico, Peter J., Bonds, Thomas L. Jr., Wallace, Robert L., Schaedler, Richard E., Tejani, Aziz A.
• Granted Patent: US 8,015,293 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: H04L 41/00 Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
• CPC Class Codes: H04L 51/043 using or handling presence information
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/2539 Hiding addresses; Keeping addresses anonymous
• CPC Class Codes: H04L 61/4523 using lightweight directory access protocol [LDAP]
• CPC Class Codes: H04L 61/4552 Lookup mechanisms between a plurality of directories; Synchronisation of directories, e.g. metadirectories
• CPC Class Codes: H04L 61/4588 containing mobile subscriber information, e.g. home subscriber server [HSS]
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 67/306 User profiles
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 8/06 Registration at serving network Location Register, VLR or user mobility server
• CPC Class Codes: H04W 8/12 between location registers or mobility servers
• CPC Class Codes: H04W 8/18 Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data
• CPC Class Codes: H04W 8/20 Transfer of user or subscriber data
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14

Abstract

Methods, systems, and computer program products for clustering and communicating between Internet protocol multimedia subsystem (IMS) entities are disclosed. According to one aspect, an IMS cluster node includes a serving call state control function (S-CSCF) for controlling media sessions between IMS users. The cluster node further includes a home subscriber service (HSS) function for storing and providing IMS subscription information to the S-CSCF function. A shared memory is operatively associated with the S-CSCF function and the HSS function. The S-CSCF function obtains IMS subscription information from the HSS function via the shared memory.

Claims

1. A system for clustering and communicating between Internet protocol (IP) multimedia subsystem (IMS) entities, the system comprising:

(a) an interrogating call state control function (I-CSCF) module adapted to receive a communication-session-related message containing a network subscriber identity;

(b) a serving call state control function (S-CSCF) module adapted to retrieve network subscriber information corresponding to the network subscriber identity and process communication-session-related messages based on the retrieved network subscriber information; and

(c) a local area communications medium coupled to the I-CSCF module and the S-CSCF module through which the I-CSCF module and S-CSCF module are adapted to communicate with each other, wherein the communication-session-related message is forwarded by the I-CSCF module to the S-CSCF module over the local area communications medium.

2. The system of claim 1 wherein the S-CSCF module includes a home subscriber server (HSS) processor adapted to provide network subscriber database services.

3. The system of claim 2 wherein the S-CSCF module includes an S-CSCF processor and a shared memory for communicating subscriber information between the HSS processor and the S-CSCF processor.

4. The system of claim 1 wherein the S-CSCF module includes an abstracted profile server (APS) processor adapted to interface with a network database and to cache subscriber information received from the network database.

5. The system of claim 4 wherein the S-CSCF module includes an S-CSCF processor and a shared memory, wherein the abstracted profile server and the S-CSCF processor exchange subscriber information via the shared memory.

6. The system of claim 1 wherein the I-CSCF module includes a subscriber location function (SLF) for identifying the S-CSCF module as the serving S-CSCF module for a subscriber corresponding to the network subscriber identity.

7. The system of claim 1 wherein the local area communications medium comprises a bus interconnecting the I-CSCF module and the S-CSCF module.

8. The system of claim 1 wherein the local area communications medium comprises a local area network interconnecting the I-CSCF module and the S-CSCF module.

9. An Internet protocol (IP) multimedia subsystem (IMS) cluster node, the IMS cluster node comprising:

(a) a serving call state control function (S-CSCF) module for controlling media sessions between IMS users;

(b) a home subscriber service (HSS) module for storing and providing IMS subscription information to the S-CSCF module; and

(c) a shared memory operatively associated with the S-CSCF module and the HSS module, wherein the S-CSCF module obtains IMS subscription information from the HSS module via the shared memory.

10. A system for implementing a plurality of Internet protocol (IP) multimedia subsystem (IMS) functions, the system comprising:

(a) a first IMS module for implementing a first IMS function associated with establishing and controlling communication sessions between IMS users;

(b) a second IMS module for implementing a second function associated with establishing and controlling communication sessions between IMS users; and

(c) a local area communications medium for connecting the first and second IMS modules and thereby forming an IMS cluster.

11. The system of claim 10 wherein the first IMS module comprises a serving call state control function (S-CSCF) module and the second IMS module comprises a home subscriber service (HSS) module.

12. The system of claim 10 wherein the first IMS module comprises a serving call state control function (S-CSCF) module and wherein the second IMS module comprises an abstracted profile server (APS) module for communicating with a home subscriber service (HSS) node.

13. The system of claim 10 wherein the first IMS module comprises an interrogating call state control function (I-CSCF) module and wherein the second IMS module comprises a serving call state control function (S-CSCF) module.

14. The system of claim 10 wherein the local area communications medium comprises a bus.

15. The system of claim 10 wherein the local area communications medium comprises a local area network.

16. The system of claim 14 wherein first and second IMS functions are components of the same network node.

17. The system of claim 10 wherein at least one of the first and second IMS modules includes a network address known only to nodes within the IMS cluster.

18. The system of claim 10 comprising a network address translator (NAT) for hiding a network address of at least one of the first and second IMS modules from nodes external to the IMS cluster.

19. A system for identifying an IP multimedia subsystem (IMS) cluster node adapted to serve a particular subscriber, the system comprising:

(a) an IMS cluster node location database including entries corresponding to IMS subscriber identifiers and identifying IMS cluster nodes for serving subscribers corresponding to the IMS subscriber identifiers; and

(b) an IMS cluster node location function for performing lookups in the cluster node location database for identifying an IMS cluster node among a plurality of IMS cluster nodes for serving a particular subscriber.

20. The system of claim 19 wherein the IMS cluster node location database includes a first portion indexed by ranges of IMS subscriber identifiers.

21. The system of claim 20 wherein the IMS cluster node location database includes a second portion indexed by individual IMS subscriber identifiers.

22. The system of claim 19 comprising a number portability database, wherein the IMS cluster node location function is adapted to perform a lookup in the number portability database to determine whether a subscriber has been ported out of a network.

23. A system for providing IP multimedia subsystem (IMS) service to IMS subscribers, the system comprising:

(a) a first IMS cluster node for providing IMS service to a first group of IMS subscribers; and

(b) a second IMS cluster node for providing IMS service to a second group of IMS subscribers, wherein the first IMS cluster node is adapted to forward IMS messages that are intended for the second group of subscribers to the second IMS cluster node.

24. The system of claim 23 wherein the first IMS cluster node includes a service location function (SLF) for identifying the second IMS cluster node as the serving node for a received IMS message concerning a subscriber in the second group.

25. The system of claim 23 comprising a third IMS cluster node adapted to serve a third group of IMS subscribers, wherein, in response to receiving an IMS message concerning a subscriber in the third group, the first IMS cluster node is adapted to forward the IMS message to the second IMS cluster node and the second IMS cluster node is adapted to forward the query message to the third IMS cluster node.

26. A method for communicating IP multimedia subsystem (IMS) information between IMS functions, the method comprising:

at an IMS cluster node;

(a) receiving an IMS registration message;

(b) requesting IMS subscription information from a home subscriber service (HSS) function within the IMS cluster node via shared memory; and

(c) providing the requested IMS subscription information via the shared memory.

27. A method for locating an IMS cluster node among a plurality of IMS cluster nodes for processing an IMS message, the method comprising:

(a) receiving an IMS message requiring processing by an IMS cluster node;

(b) performing a lookup in at least one database and identifying an IMS cluster node of a plurality of IMS cluster nodes for processing the IMS message; and

(c) forwarding the message to the identified IMS cluster node.

28. The method of claim 27 wherein performing a lookup in at least one database includes performing a lookup in a first database indexed by individual IMS subscriber identifiers to locate an IMS cluster node for processing the IMS message.

29. The method of claim 28 wherein performing a lookup in at least one database comprises, in response to failing to locate a matching entry in the first database, performing a lookup in a second database indexed by ranges of IMS subscriber identifiers.

30. A computer program product comprising computer executable instructions embodied in a computer readable medium for performing steps comprising:

at an IMS cluster node;

(a) receiving an IMS registration message;

(b) requesting IMS subscription information from a home subscriber service (HSS) function within the IMS cluster node via shared memory; and

(c) providing the requested IMS subscription information via the shared memory.

31. A computer program product comprising computer executable instructions embodied in a computer readable medium for performing steps comprising:

(a) receiving an IMS message requiring processing by an IMS cluster node;

(b) performing a lookup in at least one database and identifying an IMS cluster node of a plurality of IMS cluster nodes for processing the IMS message; and

(c) forwarding the message to the identified IMS cluster node.