Self-healing in wideband packet networks

A brief overview is given of wideband packet technology (WPT), with special attention to the features affecting the feasibility of self-healing, a method for automatic failure recovery proposed herein. The objectives of self-healing are set forth, and the failure detection strategy is described. With this strategy, nondisruptive trunk monitoring (self-monitoring) at the data link layer of an open system interconnection (OSI) reference model is performed to detect facility failure of under 1 s. The bit error rate (BER) on a transmission link is estimated on the basis of counts of the number of packets with cyclic redundancy check (CRC) errors at the data link layer. This failure detection strategy can respond to link failures for any given traffic mix by the provisioning of duration and level of unacceptable sustained BER. The mechanisms used to achieve recovery in frame-relay networks using packet streams to carry users' traffic are discussed. Provisioning of the WPT nodes and the network is addressed.<
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