Based On Wavelength Path Cell Wdm Optical Network Routing Algorithm Research

It is urgent to increase bandwidth and improve delivery efficiency for currentcommunication networks to accommodate the continual development of networkservices. Wavelength Division Multiplexing (WDM) technology can extend thetransmission capacity of a single fiber to tens even hundreds times. The problem ofrouting and wavelength assignment (RWA) is one of the most important problem inWDM optical networks, and advanced RWA algorithm can efficiently utilize the limitednetwork resources. Additionally, the path computation element (PCE) provides apowerful computing capability for routing in large-scale optical networks.Therefore, this thesis concentrates on RWA algorithms based on PCE for WDMoptical networks in both single domain scenario and multi-domain scenario.In chapter1, the development history, research situation and main problems ofoptical fiber communication are introduced, and the appearance of the PCE is alsodescribed in this section.In chapter2, the traditional WDM optical network RWA problem is discussed andsome classic RWA algorithms are compared. The background, architecture, networktechnology and the application in WDM network of PCE is also introduced.The PCE-based RWA algorithm for single domain WDM networks is investigatedin chapter3. An improved RWA algorithm named wavelength plane sequence scheme(WPSS) based on virtual wavelength topology is proposed, after intensive evaluationvarious existing related RWA algorithms. The simulation results show that the algorithmcan reduce the business network blocking rate, and improve the overall performance ofthe network.In chapter4, for multi-domain optical networks scenario, a mathematical model ofPCE based RWA for multi-domain optical networks is given to describe the works andcommunication mechanism in multi-domain optical networks of PCE. Then across-domain RWA algorithm (MD_WPSS) using PCE is proposed. The algorithmcombines the function of both virtual topology and BRPC, also introduces the loadconstraint and wavelength continual constraint. The simulation result shows that the proposed algorithm can effectively reduce the blocking rate of the network services andconsuming less wavelength resources.The main contribution and innovation of this thesis include two aspects; thePCE-based RWA algorithm for single domain WDM networks is discussed firstly.Based on the traditional RWA algorithms, this thesis apply the virtual wavelength planetechnology to PCE based optical network, and proposed an improved RWA algorithmagainst the wavelength continuity constraint. The simulation results show that thealgorithm can reduce the network congestion rate effectively. Then, the RWAtechnology for multi-domain optical networks is considered. Since PCE can resolve themultiple constraints RWA problem, this paper adds the wavelength continuity constraintand the load constraint to the BRPC algorithm, and proposed an improved BRPCscheme. The simulation results show that the new scheme can reduce the networkcongestion rate effectively and improve the efficient use of network resources.