Method and system of managing a call in a telecommunication system

A telecommunication system including a network having at least one call controller effecting a call control function and at least one bearer controller effecting a bearer control function, the call controller and the bearer controller separated by a vertical control protocol interface, said system being operable to acquire information, from at least one message communicated within said system, relating to the capability of the at least one bearer controller to modify a characteristic of a bearer during an active phase of a call, the system also being operable to receive a request to modify a bearer characteristic during an active phase of a call, said system including:

• a first means for retrieving said acquired information to determine whether the request can be satisfied;
• a second means for modifying a bearer characteristic of an existing bearer when the at least one bearer controller includes a capability of bearer characteristic modification signalling;
• and
• a third means for selecting at least one of a plurality of bearers having required bearer characteristics when the at least one bearer controller does not include a capability of bearer characteristic modification signalling;
• wherein upon determination by said first means that a request can be satisfied, the second and third means are used to satisfy the request.

A media gateway controller being operable to:

• request, receive, and store indications, from at least one media gateway, of the capability of the at least one media gateway to modify a characteristic of a bearer established by the at least one media gateway;
• receive a call control message indicating that the characteristic of the bearer should be modified;
• and
• check said stored indication to determine whether the characteristic of the bearer can be modified.