Call control with converged application server logic and gateway logic in IMS networks

A method of operating an IP Multimedia Subsystem (IMS) call control node for providing online charging in an IMS network, wherein the IMS call control node comprises a first interface for communicating with a call session control function (CSCF) according to a first protocol, a second interface for communicating with an online charging server (OCS) according to a second protocol, a processing system coupled to the first interface and the second interface, Application Server (AS) logic, and gateway logic, the method comprising:

• receiving a call message in the processing system from the CSCF through the first interface according to the first protocol,
• determining whether to execute the AS logic or the gateway logic responsive to the call message,
• executing the AS logic in the processing system to perform a service responsive to a determination to execute the AS logic,
• executing the AS logic in the processing system to contact the OCS for online charging for the service through the second interface according to the second protocol,
• executing the gateway logic in the processing system to perform call session control responsive to a determination to execute the gateway logic, and
• executing the gateway logic in the processing system to contact the OCS for online charging for a call session through the second interface according to the second protocol.

An IP Multimedia Subsystem (IMS) call control node for providing online charging in an IMS network, the IMS call control node comprising:

• an IMS service control (ISC) interface operable to communicate with a call session control function (CSCF) according to ISC protocol;
• an Ro interface operable to communicate with an online charging server (OCS) according to Ro protocol;
• a processing system coupled to the ISC interface and the Ro interface;
• application server (AS) logic executable by the processing system to provide a plurality of services;
• and
• gateway logic executable by the processing system;
• the processing system:
• receives a call message from the CSCF through the ISC interface according to the ISC protocol,
• determines whether to execute the AS logic or the gateway logic responsive to the call message,
• executes the AS logic to perform a service responsive to a determination to execute the AS logic, and executes the AS logic to contact the OCS for online charging for the service through the Ro interface according to the Ro protocol, and
• executes the gateway logic to perform call session control responsive to a determination to execute the gateway logic, and executes the gateway logic to contact the OCS for online charging for a call session through the Ro interface according to the Ro protocol.