Service circuit allocation in large networks

A method of allocating a service circuit for a call, comprising the steps of:

• storing and updating, in a regional control node, availability data for a pool of service circuits serving a region;
• responsive to a request from any of a plurality of switching systems of said region, for a service circuit, selecting an available one of said pool of service circuits for serving said call;
• and
• controlling establishment of call connections between the selected service circuit and said call from said regional control node;
• wherein the step of selecting comprises:
• consulting a topology manager of said regional control node to minimize resource utilization for connecting the selected service circuit to the call.

A method of allocating a service circuit for a call, comprising the steps of:

• storing and updating, in a regional control node, availability data for a pool of service circuits serving a region;
• responsive to a request from any of a plurality of switching systems of said region, for a service circuit, selecting an available one of said pool of service circuits for serving said call;
• and
• controlling establishment of call connections between the selected service circuit and said call from said regional control node;
• wherein the step of selecting comprises selecting at least two different types of service circuits for serving a multi-media call;
• wherein call connections of at least two of said different types of service circuits use paths via different ones of said switching systems of said region.

A method of allocating transmission resources of a regional telecommunications network to a call, comprising the steps of:

• maintaining, in a regional control node, availability data for said transmission resources for interconnecting nodes of said network;
• responsive to a request from any switching system of said region, for a transmission resource, selecting an available transmission resource for serving said call;
• and
• controlling establishment of call connections using said selected transmission resource from said regional control node;
• wherein the step of selecting comprises consulting a topology manager of said regional control node to minimize transmission resource use for said call.