Study On Protection Technique Of Optical Layer In Next Generation Optical Network

As the fast development of optical communication, the next generation optical network (NGON) is growing to be a large-scaled mesh network, which is more client-oriented and intelligent. This trend raises many new and strict requirements for network survivability.Protection of optical layer is one of the most important techniques for network survivability. Former studies were mostly based on small single-layer networks and don't work well in NGON. In this paper, we discussed in details the requirements for protection in NGON. Then we proposed two new techniques, Domain Reciprocate Sup-Path Protection (DR-SPP) for multi-domain networks and Hybrid Protection Restoration Framework (HPRF) for hierarchical networks.In DR-SPP, working links in each domain are protected by neighboring domains, and there is no need for neighboring domains to share border nodes as is required in some former techniques. Neither redundant physical nodes nor any other additional restriction for network partition are needed, which ensures flexibility of the network.In HPRF, according to hierarchical network structure, we introduced a policy in which protection and restoration are used for inter-domain and intra-domain failures respectively. HPRF can guarantee favorable resource efficiency and fast recovering speedWe developed signaling processes for DR-SPP and HPRF, discussed about their requirements for the network and reviewed some of their performance. Besides, we do computer simulations to evaluate the performance of DR-SPP and HPRF. By comparing to previous path protection, we concluded that both DR-SPP and HPRF are favorable for NGON.