| 摘要 |
<p>The invention relates to communications systems, and particularly to enhanci ng tolerance to failures in network elements and transmission systems. The faul t tolerance is achieved by 1) providing two or more active ATM permanent virtu al channel (PVC) connections (31a-31d) between a core network element (3G-SGSN) and an access network element (RNC), and 2) providing a separate ATM interfa ce 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 ov er 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. A ny new communication will be setup over the other connections.</p> |
