Research On Protection Technology For Mesh Optical Network

Mesh network is becoming the best network organization mode of core transport network. A failure of a network component can lead to a severe disruption in the traffic, therefore, the survivability of mesh network has become a topic worthy of study. Protection and restoration are two vital technologies which greatly impact the performance of optical networks, so they are the basic method to solute the network survivability.In this dissertation, our research work focuses on static protection technology in mesh network. As p-cycle (Pre-Configureted Protection cycle) can achieve ring-like fast protection speed and mesh-like high efficiency of spare capacity, we choose p-cycle as our research aspect. The single failure and dual-failure protection in p-cycle network are described in detail. Several new ideas and algorithms for solving these problems are put forward by author in this dissertation.The basic concept of p-cycle and p-cycle protection scheme in mesh network are introduced in chapter 3. Based on existed algorithms for configuring p-cycles, we consider a new heuristic method for design of survivable mesh networks with p-cycle. The heuristic algorithm selects the cycle with the minimum redundancy ratio from all the candidate cycles every time until all the working capacity are protected. Simulation results show that the redundancy obtained by the heuristic algorithm is lower than Grow algorithm, and very close to that of the ILP(Integer Linear Programming) algorithm; in addition to this, it can reduce the computing time versus ILP algorithm.In large networks or where maintenance activities reduce the available spare capacity, dual-failures may become the dominant factor in determining the ultimate service availability of those networks. We propose a algorithm of dual-failures restorability based on SLA algorithm which follows the rule of"A Static p-cycles Protection Deployment Rule for Dual Span Failures"in chapter 4. Simulation results show that this algorithm can achieve dual-failure 100% protection, but also to provide a higher utilization rate of resources.