An efficient resource sharing scheme for dependable real-time communication in multihop networks

Many real-time applications require communication services with guaranteed timeliness and fault-tolerance capabilities. Hence, we have the concept of a dependable connection (D-connection), which is a fault-tolerant real-time connection. A popular method used for a D-connection establishment is the primary-backup channel approach, wherein a D-connection is setup by the establishment of a primary and a backup path. But, we note that such a 100% dependable network is very inefficient. We introduce an efficient scheme called primary-backup multiplexing where D-connections may share their backup paths with other connections. We also describe a method where a D-connection can be given an intermediate fault-tolerance level between 0% dependability (no backup channel) and 100% dependability (dedicated backup). We present an efficient, connection-oriented and fault-tolerant D-connection establishment and resource-sharing scheme for real-time communications. We have noted in the simulation studies, that at light load, our scheme can effect a considerable improvement in the network resource utilization, with a relatively low drop in its fault-tolerance capabilities.