Restoration algorithms in multi-layer multi-domain optical network with traffic grooming capacity

This thesis concentrates on restoration algorithm of multi-layer multi-domain grooming optical network. Abrupt breakdown will lead to a large number of business interruption and bring serious consequences. Therefore, the survivability problem of optical network is very important. Restoration algorithms are significant contents of survivability technology. Because grooming algorithm and restoration algorithm have common feature in nature, combining both of them is a feasible scheme. Firstly, a novel inter-domain grooming algorithm named IDGA is proposed to solve the problem of inter-domain business grooming, which uses intra-domain grooming algorithm to search minimum cost link between source node and gateway node in source domain. Using the same method to search minimum cost link between gateway node and destination node at the same time. So inter-domain grooming is achieved by two gateway nodes for the propose of establishing connection for low-speed business. On the basis, a multi-layer multi-domain restoration algorithm (MMRA) against four kinds of network faults including router fault, OXC fault, optical fiber fault and mixed fault is raised. When the network fault occurs, the fault recovery node will start restoration algorithm according to the fault type and location. Simulation evaluation shows that the proposed algorithm is effective in reducing restoration time and blocking ratio, improving the resource utilization ratio and fault recovery ratio.