Research On Dynamic Multicast Routing Algorithm In WDM Networks With Multi-constraints

With the development of network technologies and the variety of user's requirements,multicast applications such as video confereneing,high-definition television, interactive distance learning, and distributed games become widely popular. On the other hand, the emergence of wavelength-division multiplexing (WDM) technology has made it possible for a single fiber to provide vast amount of bandwitdths and opened the gates for bandwidth-intensive multicast applications. Therefore, the problem of supporting multicasting in WDM networks has a research topic in recent years. There are some special constraints in optical layer multicast, including the wavelength continuity constraint, sparse light splitter configuration constraint and energy injury constraint. Because the multi-constrained multicast routing calculation is very complicated and difficult to achieve, many of the current methods are studying the multicast RWA problem under one or two constraints. The main content that the paper studies is the RWA problem under the wavelength continuity constraint, sparse light splitter configuration constraint and a certain delay requirement of a application. The paper gave out tow RWA algrithms MCCA-G and MDCA-G based on generic layer auxiliary graph model to maximize the network capacity and reduce the request blocking propability.Firstly, the paper compares the previous multicast routing and wavelength assignment algorithms, summarizes their advantages and disadvantages. Next, design tow routing and wavelength assignment algorithms based on generic layer auxiliary graph model:MCCA-G minimum cost controls algorithms-graph and MDCA-G minimum delay dontrol algriths-graph. The two algorithms both adhibit MPH and the thought of entering the wavelength layer with minimum cost rates, And the latter should be better than the former to the control the delay of request. In addition, for sparse the splitters and wavelength converters put and exert a tremendous influence to the performance of the network, the paper have proposed a SNPA algorithm i.e. sparse nodal position algorithm as to this test of this point. In simulation sparse nodal position adopt the result of calculation of SNPA sparse node of MCCA-G and MDCA-G, Artificial result indicate that MDCA-G in blocking rates respect reduce 8.5%?15.34% smaller than traditional RRS algorithm, and MCCA-G compare to Member-only and VS-Based reduce 31.08% and 16.19% in blocking rates. It can be seen under the same conditions, MCCA-G and MDCA-G algorithm have better performance than those traditional algorithms.