| 摘要 |
A telecommunications system for providing internet protocol multi-media services in accordance with a service level agreement specifying conditions for a communications session in which internet protocol data is communicated to and from a mobile user equipment is provided. The system comprises an internet protocol multi-media sub-system operable to provide the internet protocol multi-media communications session to the mobile user equipment, a mobile access network for providing a mobile communications facility to the mobile user equipment for the internet protocol multi-media communications session, and a signal transfer point. The signal transfer point is operable to receive signalling data messages communicated to and from the mobile access network for providing the internet protocol multi-media communications session, to receive subscriber data of the mobile user equipment communicated to the mobile access network from the home location register of the mobile user equipment as part of a communications session establishment procedure, the subscriber data including data representing the service level agreement for providing the multi-media communications session, and to set triggering conditions, based on the subscriber data, in the mobile access network in accordance with the service level agreement. The system also comprises a local access control function operable in response to reporting messages received from the mobile access network generated by the mobile access network when the triggering conditions are satisfied to determine whether the mobile user equipment is communicating in accordance with the service level agreement, and to control the multimedia communications session in accordance with the service level agreement. By setting the triggering conditions in the mobile access network in this way, a local access control function associated with the mobile access network can assume control over communications to and from the user equipment. |
