Provision of network survivability using Restricted P-Cycle

Abstract

Mesh-restorable transport network offers a number of advantages, such as low capacity redundancy and flexible signal management. However, a disadvantage of mesh based recovery is that its recovery speed may not be fast enough to prevent voice and data connections from being dropped. So in the recent recovery mechanisms having efficiency like mesh and recovery speed like ring are investigated. P-cycle in previous researches has established that it is technically possible to have speed like ring. However, due to the complexity of determination of applied patterns, it may not be possible to implement pattern change in real time according to call demands. We propose the new method, RPC, that can provide fast recovery and capacity efficiency as well as reduce complexity of algorithm. It can find patterns adaptively according to varying call demands and so can be applied to the real operational network .We also suggest a way of guaranteeing QoS of network when RPC is applied. Additionally, we propose sub-RPC that applied RPC to smaller partitioned network. As sub-RPC is applied to small networks, end-to-end delay is very small. In addition, sub-RPC provides scalability of network and recovers partial multiple failures. Simulation results show that RPC can achieve great reduction of complexity and almost same restorability compared to p-cycle. Simulation result also shows that recovery time of RPC is very faster, but occasionally end-to-end delay can be longer. We show that sub-RPC can solve problems related to QoS and non-Hamiltonian graph.