Pre-Allocated Restoration Technique in a Distributed GMPLS-Based IP/WDM Mesh Network

Since IP over WDM networks have been identified as a promising candidate for the structure of future telecommunication networks, both industry and researchers have been considering various issues that affect the integration of IP and the optical layer. One key issue is network survivability. The main challenges in this domain are: to provide survivability schemes under different failure scenarios and to significantly reduce the amount of required spare capacity while providing the required quality of service (QoS). A candidate technique, due to its flexibility and simplicity, is the pre-allocated restoration technique. In this paper, the pre-allocated restoration performance is investigated under single and dual-link failures considering a distributed GMPLS-based IP/WDM mesh network Three main issues are considered in this paper. Firstly, ´the spare capacity allocation problem´ is investigated, involving decisions based on the method to allocate the spare capacity. Secondly, the paper evaluates a retrial method that supports the utilisation of spare capacity. Finally, the differentiated survivability concept that supports quality of service with pre-allocated restoration is investigated