An M: NN Shared Regenerator Protection Scheme in Translucent WDM Networks

Most studies addressing translucent network design targeted a tradeoff between minimizing the number of deployed regenerators and minimizing the number of regeneration nodes. The latter highly depends on the carrier's strategy and is motivated by various considerations such as power consumption, maintenance and supervision costs. However, concentrating regenerators into a small number of nodes exposes the network to a high risk of data loss in the eventual case of regenerator pool failure. In this paper, we address the problem of survivable translucent network design taking into account the simultaneous effect of four transmission impairments. We propose an exact approach based on a mathematical formulation to solve the problem of regenerator placement while ensuring the network survivability in the hazardous event of a regenerator pool failure. For this purpose, for each accepted request requiring regeneration, we determine several routing paths along with associated valid wavelengths going through different regeneration nodes. In doing so, we implement an M : N shared regenerator protection scheme. Simulation results highlight the gain obtained by reducing the number of regeneration nodes without sacrificing network survivability.