This article studies multi-constraints least-cost multicast routing problem in internet protocol over dense wavelength division multiplexing (IP/DWDM) networks. To address this problem, an individual-difference-based quantum genetic algorithm (IDQGA) is proposed. This algorithm considers individual differences among chromosomes by introducing an adaptive rotation angle step determination scheme and a grouping-based quantum mutation operation. Simulations are conducted over network topologies. The results indicate that compared with other heuristic algorithms, IDQGA has better optimal performance on solving quality of service (QoS) multicast routing problem in IP/DWDM networks and is characterized by strong robustness, high success ratio and excellent capability on global searching.
National R&D activities on optical switching networkare introduced. Optical switching network testbedswere established in China including 3T-net andOBS ring and mesh network test-bed with the supportof national '863' program. As an importantmodule in OPS network, a novel all-optical serialmulticast mode is discussed.
The article proposes a network parameter-awareness (NPA) method and applies it to routing discovery algorithms in autonomic optical Internet. This NPA method can perceive the main parameters of the network, such as delay, jitter and traffic, which can represent the current situation of the network. And these parameters enable network to determine the appropriate nodes for routing discovery. The simulation results of evaluating performance of a network with NPA method and its routing applications show that the method and its applications in routing improve the performance of the network significantly with quality of service (QoS) guaranteed.
JIN Jin WANG Hong-xiang JI Yue-feng Key Laboratory of Optical Communication and Lightwave Technologies,Beijing University of Posts and Telecommunications,Beijing 100876,China
针对现有 MPLS 光波长路由器存在 IP 层和光层分别路由的不足,提出了一种使用了联合路由算法的自适应路由策略,该路由策略可以适应流量疏导端口资源的变化,合理利用波长和流量疏导端口,提高网络性能和资源利用率。同时为了支持该路由策略,还提出了一种辅助拓扑的构造方法。仿真结果显示,该自适应路由策略具有更好的性能,可以承载更多的业务。
An optical burst switching (OBS) network platform is established with a ring topology of three nodes. A congestion Mleviated scheme using advanced token protocol and wavelength tunable receivers is demon- strated to optimize the network platform. Experimental results testify that this scheme can resist collision at the level of 0.1% congestion rate.