Robust Programming Algorithm For Wdm Optical Networks Traffic Grooming

With the explosive increase in network traffic and the emergence of high performance optical network devices, such as optical cross-connect (OXC) and optical add/drop multiplexer (OADM), wavelength division multiplexing (WDM) technology becomes the core technology of next generation backbone networks. In WDM networks, routing and traffic grooming have been widely investigated, mostly with the condition that network requirements are determined. However in actual applications, it is usually difficult to acquire the exact traffic between all nodes in the network (named traffic matrix).In this paper, we investigate the problem of robust resource provision and robust routing in WDM mesh networks under uncertain traffic matrix (hose model). Valiant load-balancing technique and traffic grooming method are used throughout our investigation.Hose model was initially proposed in VPN (Virtual Private Network), and is used for WDM mesh networks in our paper. In hose model, there is no need to get the exact network traffic matrix, while what should be specified are the aggregate outgoing traffic from every node into the network and the aggregate incoming traffic out of the network to each node.Valiant load-balancing uses two-stage routing policy, though which the traffic from each source point of the network is distributed to all nodes according to the load distributing ratio, and then is transmitted by every middle point to destination point. Traffic grooming is used to efficiently set up connections for low rate traffic streams, while it is impossible to establish end-to-end light paths for all the connection requests, due to the limits of the number of wavelengths per fiber and the number of transceivers per node.In this paper, based on above model and techniques, we proposed some novel heuristic algorithms through introducing the conception of node fan-out. These new routing algorithms can be divided into two groups: one of them is to minimize the network cost with the condition of uncertain traffic matrix; the other is to maximize the network throughout with the condition of uncertain traffic matrix and decided network resource.With the condition of uncertain traffic matrix, in order to minimize the network cost, two novel heuristic routing algorithms was proposed in chapter 3: MTFO (Minimizing Total node Fan-Out) and MNFO (Minimizing Network Fan-Out).With the condition of uncertain traffic matrix and decided network resource, in order to maximize the network throughout, two novel heuristic routing algorithms was also proposed in chapter 4: MTRF (Maximize Total Reciprocal Fan-out) and MMRF (Maximize Minimum Reciprocal Fan-out).In chapter 5, combined these routing algorithms proposed in chapter 4 with two old algorithms SPR&MHF (Shortest Path Routing, Minimizing Hop First) and BR&MHF (Balanced Routing, Minimizing Hop First), we further get four new routing algorithms: MTRF-SPR (Maximize Total Reciprocal Fan-out, Shortest Path Routing), MMRF-SPR (Maximize Minimum Reciprocal Fan-out, Shortest Path Routing), MTRF-BR (Maximize Total Reciprocal Fan-out, Balanced Routing), MMRF-BR (Maximize Minimum Reciprocal Fan-out, Balanced Routing).Chapter 3 also gives the algorithm of light path traffic grooming, related with these new routing algorithms proposed in chapter 3 to 5. Combined with grooming algorithm, these routing algorithms mentioned-above can preferably solve the problem of robust design in WDM mesh networks.To verify and evaluate the algorithms proposed in this paper, computer simulation programs are developed. Base on these programs, the performance of all proposed algorithms is evaluated and compared.