频谱可用性和保护带宽共享度感知的弹性光网络生存性多路径策略

摘要

In order to address the problems of the low Spectrum Utilization (SU) and the high Bandwidth Blocking Probability (BBP), a survivable Multipath strategy based on Sharing Degree of protection bandwidth and Spectrum Availability-Aware (M-SDSAA) is proposed. Firstly, the single-path routing is used to transmit the request. The first fit and last fit methods are adopted according to the request duration for the working path Routing and Spectrum Assignment (RSA). A link weight value is designed in accordance with the size of sharable spectrum block. Secondly, the multipath RSA mechanism is used to transmit the request when the single-path RSA fails. The multipath RSA adaptively chooses multiple paths priority with less number of spectrum slots to transmit the request. A shared light-path protection mechanism is used for the multipath provision. Lastly, a reprovisioning mechanism is proposed to further reduce the BBP when the request is blocked. This mechanism reconfigures the blocked request from the sub-optimal protection path to the optimal path occupied minimum protection bandwidth. The simulation results show that the M-SDSAA can improve the SU and decrease the BBP.%针对弹性光网络频谱利用率降低和带宽阻塞率高等问题,该文提出一种频谱可用性和保护带宽共享度感知的生存性多路径策略(M-SDSAA).首先,该策略对业务采用单路径路由,通过区分业务的持续时间,分别采用首次命中和末端命中的工作路径频谱分配方式,并且为不同大小共享频谱块设定不同链路权重值.若单路径路由或频谱分配失败,引入多路径传输策略,自适应选择消耗频隙数少的策略,并且引入共享保护机制,提高保护带宽共享度.最后,当业务阻塞时,且存在单路径业务的保护路径预置在频隙消耗次优的路径,则启动重配置机制进一步降低阻塞率,将该业务重配置到保护频隙消耗最少的路径.仿真结果表明所提算法能有效地提高频谱利用率,降低网络的带宽阻塞率.