Abstract: To segregate functionality and to eliminate redundancy in service logic and associated hardware that together control the interconnection of narrowband trunk circuits (252-256) and broadband virtual channels (258-262) of a mixed node communication system (FIG. 5), a switch fabric (16) has an associated memory (280) that contains a pre-provisioned table of mappings between narrowband trunk circuits (DS-0s) and broadband virtual channel identities. Therefore, to establish an end-to-end connection, the switch fabric (16) searches the pre-provisioned table (280) for an available connection and then performs the necessary cross-connection between the narrowband trunk circuit is (252-256) and the broadband virtual channel (258-262). The mappings principally relate to the narrowband-to-switch fabric interface and, as such, avoid the requirement for UNI signalling translation and negotiation, although the mappings may also include the broadband-to-switch fabric interface.

Abstract: A connection broker (44), located between lower-level system entities (16, 58, 264) associated with a narrowband-broadband interface (250) and a call server (18) that controls call connection across the narrowband-broadband network, contains a memory (251) that stores connection-related information and protocol converters. The connection broker (44) accesses the protocol converters to interpret control messages received from the call server (18) and, where necessary, transposes messages for the call server into a standardised format for use over a uniform fabric application interface (66). Control messages pertaining to connection paths within the narrowband-broadband network (250) and relayed via the connection broker (44) are appropriately phrased (by the connection-related information and protocol converters) to ensure that meaningful information and instruction is communicated between the call server (18) and the lower-level system entities (16, 58, 264).

Abstract: A number of narrow band networks are interconnected via a broad band network having a signalling protocol different from that or those of the narrow band networks. Calls between terminals associated with first and second narrow band networks are set up by the selection by a call server of a phantom trunk between the networks. This phantom trunk is used to relay the addresses of the two terminals to be connected. By recognizing that two connection requests have been received at opposite ends of the same phantom trunk, a processor in the second network determines that a connection between the terminals via the broad band network is required. Selection of the phantom trunk and sending of address messages is effected via a selected one of a number of identical connection brokers coupled to the call server. The workload of the call server is shared among the connection brokers coupled thereto.