A Generalized Strategy for 1+N Protection
Ahmed E. Kamal · 2008
1+N protection was proposed by the author in [1], where a single circuit is used to protect a number of connections. For this purpose, network coding was used to carry a linear combination of the signals, and p-Cycles were used to provide this combination to the destination nodes in order to allow them to extract a second copy of the transmitted signal. In this paper, we introduce a generalized form of 1+N protection. Network coding is used to combine a number of signals on one protection circuit. However, p-Cycles and not used, and the signals are combined on a protection circuit, which is optimally selected to minimize the amount of protection resources. Moreover, and unlike the strategy in [1], the generalized strategy does not require symmetry in resource reservation in the two directions of communication, but the protection resources are provisioned based on need. The strategy introduced in this paper provides 100% protection against single link failure on any of the working paths. A performance comparison between the cost of implementing the proposed scheme and 1+1 protection is provided, and is based on integer linear programming formulations.