WDM网状网络中一种动态多播自适应业务疏导算法

An adaptive algorithm for dynamic multicast traffic grooming in WDM mesh networks

光多播业务需要消耗大量的WDM光网络带宽资源,业务疏导是光多播网络降低业务请求阻塞率和提高带宽资源利用率的有效方法。提出了一种新型光多播疏导节点结构,研究了疏导端口优先的多播业务疏导算法(TGPFA)和新建光树优先的多播业务疏导算法(TCLFA),进而提出了一种能够适应网络资源变化的动态多播业务疏导算法(ADMGA)。结果表明,在网络资源有限的情况下,ADMGA算法能取得较低的请求阻塞率和带宽阻塞率,获得较好的网络性能。

Optical multicast traffics need to consume a large number of wavelength division multiplexing （WDM） optical network bandwidth resources, and the gap between the bandwidth capacity offered by a wavelength and the bandwidth required by the multicast request is very large. So,traffic grooming is an effective method adopted to reduce the traffic request blocking probability and to improve the utilization of wavelength bandwidth resources for optical multicast networks. A novel optical multicast traffic grooming node architecture with two-level switching is proposed in this paper. The traffic grooming port first algorithm （TGPFA） and the traffic constructing the new light-tree first algorithm （TCLFA） are researched for the architecture respectively to reduce the traffic blocking probability. Moreover, an adaptive dynamic multicast grooming algorithm （ADMGA） based on TCLFA and TGPFA is brought forward to adapt to the network available wavelength resources dynamically. By setting a threshold function cprresponding to the network available bandwidth, the ADMGA algorithm can select the appropriate method to groom the new arriving multicast traffic request to the assigned wavelength with residual bandwidth. The simulation analysis and results show that the proposed ADMGA algorithm can reduce the request blocking probability,decrease the bandwidth blocking ratio and improve the wavelength bandwidth utilization for the WDM network with limited wavelength bandwidth resource.