改进遗传算法优化光组播网络编码链路数目  

Improved genetic algorithm to optimize the number of network coding links for optical multicast

作　　者：刘焕淋[1] 邓朗[1] 薛湘[1] 向劲松[1] 

机构地区：[1]重庆邮电大学通信与信息工程学院重庆市光纤通信技术重点实验室,重庆400065

出　　处：《光电子．激光》2014年第8期1488-1493,共6页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(61275077;61071117;51175535);重庆市科委自然科学基金(CSTC;2013BB2425;2012jjB40009);重庆市教委项目(KJ1400421)资助项目

摘　　要：光组播中使用网络编码能提高组播吞吐量、均衡网络负载和提高网络资源利用率,但会增加光组播网络节点的光域计算开销和存储开销。由于缺少光RAM,光组播网络需要尽量减少光网络中的编码操作次数,而光网络编码链路的数目可以更好地反映出编码操作次数。因此,本文提出了基于改进遗传算法(GA)的最小化编码链路算法。为了防止算法收敛速度过快陷入局部最优,算法设计了动态变异的操作,根据每一代最佳个体的适应度的变化情况确定变异概率;在算法的迭代过程中改进新个体接受策略和局部操作,不仅能保证种群的多样性,也可以提高算法的局部寻优能力。仿真结果表明,最小化编码链路算法能够有效地解决光网络中最少网络编码链路问题,能够在较短的时间内找到更少编码链路的网络编码信息传输方案。Network coding can increase multicast throughput,balance the network load and improve the utilization ratio of network resources for optical muhicast. But the network coding operation will increase the overhead of computation and requirement of storage in optical field. Due to shortage of optical RAM, we need to try the best to reduce times of network coding operations for optical networks. The link number of transmitting encoding information can represent the times of encoding operations, So the algorithm of minimizing coding links based on the improved genetic algorithm is proposed in this paper. In order to prevent the fast convergence speed making algorithm fall into a local optimal solution, the dynamic mutation is designed in the algorithm and mutation probability is determined by the change of the best individual＇s fitness in each generation. The new individual accepting strategy and local operation are improved not only to ensure the diversity of the population but also to enhance the local optimization ability of the algorithm in each round of iteration. The simulation results show that the MCLIGA can minimize the number of links for network coding in optical network and can find the optimal informanon transmitting scheme with fewer encoding links in optical network.

关 键 词：光组播 网络编码 遗传算法(GA) 动态变异 局部操作 

分 类 号：TN911[电子电信—通信与信息系统]