Research On Multicast Traffic Grooming With Sparse Light Splitter Configuration Constraint

Multicast traffic grooming is an important aspect of the multicast in optical network. Compared to the wavelength bandwidth, most of the optical network bandwidth of the business request are relatively small. If we assign a separate wavelength channel for each business request, a great waste of network resources are inevitably. To effectively solve this problem, people have been proposed traffic grooming technology. Traffic grooming is that through effectively multiplexing, demultiplexing and exchange processing technology, the business with smaller bandwidth granularity together into a high-capacity optical transmission in order to improve network resource utilization. Considering the sparse light splitter configuration reducing the energy injury, and deploying light splitter and full wavelength conversion for all nodes in the network is unrealistic in the present. So dynamic multicast traffic grooming problem with sparse splitter configuration constraint is studied in this thesis.First, I study the relevant technical of the WDM optical network multicast traffic grooming, including optical network technology, multicast implemented and the structure of network nodes. Then, I sum the existing multicast traffic grooming in three implementations: link methods, light path methods and light tree methods, and I analyze the advantages and disadvantages of three implementations. Finally, based on light tree methods, to improve the utilization of network resources, reduce blocking rate target, a new integrated multicast traffic grooming algorithm based on the auxiliary grooming graph (Comprehensive Multicast traffic Grooming Algorithm, CMGA) is proposed after in-depth analysis and studying the existing algorithms based on light tree methods. The algorithm introduces a new auxiliary graph and the graph can reflect all kinds of information of the current network, and it can save the current network of scarce resources through setting the value for the sides. The algorithm makes better use of the remained bandwidth of the existing light tree or light path in the network, and effectively reduces the blocking rate through comprehensively using three multicast traffic grooming strategies: single-hop grooming, multi-hop grooming and building new light tree.Simulation results show that compare to the existing algorithm (LF-MHG algorithm) based on the light tree method the new algorithm can more fully utilize the limited network resources and effectively reduce the blocking rate whether in different traffic load, or in different optical wavelength number, or in different multicast ratio.