P-cycle based network design to control the optical path lengths in restored state of transparent network

Normally restoration path served by efficient p-cycle for on-cycle links are quite large in length. In a transparent optical network, there is usually a limit on the length of the light paths; beyond this limit transmission quality may be affected. To sustain adequate transmission quality, regeneration may be a solution but increases the overall cost of the network. Therefore for these networks, to restrict the restored path length, systematically matching working paths with available p-cycle restoration paths was recently suggested by eminent researches. However, in some cases the results are not in acceptable level i.e. some restored path lengths are yet again in the problematical domain and controlling their length increases the requirement of spare capacity. In this paper authors, propose Enhanced Inter Cycle Switching (EICS) approach and Optimal Idle p-cycles Allocation (OIPA) to reduce and control the length of such restored paths without demanding any additional spare capacity. EICS approach exploits the idle p-cycles over the end to end restored path which integrates working path and p-cycle restoration segments.