OBS中基于优先级与负载均衡的偏射路由算法

A deflection routing algorithm based on priority and load-balancing in optical burst switching networks

为了解决偏射算法在偏射控制上的问题,提出了一种基于优先级与负载均衡的偏射路由算法。当冲突发生时,分割优先级低的突发数据包;将冲突部分的突发包偏射到空闲的链路上,并在空闲的链路中选择若干条"当前最大剩余跳数小于源-目的节点的最大跳数"的路由作为候选路由;最后,在这些候选路由中选择一条可以使网络中各链路使用波长数的统计方差最小的最佳路由。对该算法进行了理论分析和模拟仿真实验验证,取得了丢包率和时延随网络负荷变化的一系列数据。结果表明,该算法得到的端到端的传输时延位于最短路径偏射路由算法和基于负载平衡偏射路由算法之间,但是该算法能够有效地降低整个网络的丢包率,并且能够很好地保护高优先级突发数据包的完整性,从而提高整个网络的性能。

In order to solve the problem of deflection control of deflection algorithm, a deflection routing algorithm was proposed based on priority and load balancing in optical burst switching（OBS） networks. When conflict occurs, low priority bursts are segmented at first. Then, the contention part of bursts is deflected to free links. The algorithm selects many candidate routes on which the current maximum number of residual hops less than the maximum number of hops of the source-to-destination nodes. Finally, the algorithm chooses the best route that balances the assigned wavelengths of every links from candidate routes. This algorithm was analyzed in theory and simulated , and a series of data including the packet loss probability and the delay changing with network loads were obtained. Simulation results show that the delay of the proposed algorithm is located between the shortest path deflection routing algorithm and load-balancing deflection routing algorithm. It can efficiently reduce the packet loss probability of the entire network and protect the integrity of some high priority bursts. So the scheme can efficiently improve the performance of OBS networks.