COMMUNICATIONS SYSTEM HAVING ENHANCED FAULT TOLERANCE

摘要

The invention relates to communications systems, and particularly to enhancing tolerance to failures in network elements and transmission systems. The fault tolerance is achieved by 1) providing two or more active ATM permanent virtual channel (PVC) connections (31a-31d) between a core network element (3G-SGSN) and an access network element (RNC), and 2) providing a separate ATM interface unit (IU1-IU4) for each such ATM PVC connection in the core network element (3G-SGSN). The user and signalling traffic is distributed among these active connections and interface units. In case of a failure in one of the ATM PVC connections or interface units (IU1-IU4), the communication is maintained over the other connection(s) and interface unit(s). Thus, only part of the transport capacity is lost, and a total block of communication is avoided. Any new communication will be setup over the other connections.