Web services interface

Abstract

A Call Session Control Function (CSCF) entity in an IP Multimedia Subsystem (IMS) network comprises a first interface for interfacing with other entities and uses signalling in an Extensible Markup Language (XML) format. The other entities that the CSCF interfaces with can be located outside the IMS network, such as servers supporting third party IT or web-based applications, or within the IMS network. The CSCF directs XML based service requests by filtering XML messages received via the first interface.

We claim: 
     
         1 . A method of operating an IP Multimedia Subsystem (IMS) network, the method comprising:
 interfacing a Serving Call Session Control Function (S-CSCF) of a Call Session Control Function (CSCF) entity directly with at least one network entity internal to or external to the IMS network using markup language signalling to provision one or more services; and   interfacing the S-CSCF to at least one other network entity using Session Initiation Protocol (SIP) signalling.   
     
     
         2 . The method of  claim 1 , wherein interfacing the S-CSCF directly with the at least one network entity comprises interface to interfacing the S-CSCF with an application executing on the at least one network entity. 
     
     
         3 . The method of  claim 2 , wherein the application is hosted externally of the IMS network. 
     
     
         4 . The method of  claim 2  comprising:
 sending markup language signalling information from the at least one network entity to the S-CSCF; 
 receiving the markup language signalling information at the S-CSCF; and 
 using the markup language signalling information to apply the application within the IMS network. 
 
     
     
         5 . The method of  claim 2  comprising:
 sending markup language signalling information from the S-CSCF to the at least one network entity; and 
 using the markup language signalling information to control the application. 
 
     
     
         6 . The method of  claim 2 , wherein the application is a web service. 
     
     
         7 . The method of  claim 2 , comprising:
 sending markup language signalling information from the at least one network entity to the S-CSCF;   receiving the markup language signalling information at the S-CSCF; and   at the S-CSCF:   inspecting the received markup language signalling information;   comparing the received markup signalling information with stored rule data which specifies a relationship between an element in the signalling information and an action that should be taken; and   generating output data based on the basis of the comparison.   
     
     
         8 . The method of  claim 7 , comprising sending the output data to at least one network entity. 
     
     
         9 . The method of  claim 7 , wherein the rule data specifies when charging information should be generated and the method comprises generating charging information based on the comparison. 
     
     
         10 . The method of  claim 7 , wherein the rule data comprises rules of the network operator. 
     
     
         11 . The method of  claim 7 , wherein the rule data comprises rules for a subscriber. 
     
     
         12 . The method of  claim 7 , wherein the rule data comprises rules for governance of an application. 
     
     
         13 . The method of  claim 1 , wherein the S-CSCF comprises:
 a first interface configured to interface the S-CSCF directly with the at least one network entity using the markup language signalling; and   a second interface configured to interface the S-CSCF to the at least one other network entity using the Session Initiation Protocol (SIP) signalling.   
     
     
         14 . The method of  claim 1 , wherein the markup language signalling comprises signalling in an Extensible Markup Language (XML) format.