Abstract: Abstract: Based on the Hybrid Optical Switching(HOS) networks, which combine advantages of OCS and OBS, we propose a novel method to address the problem of designing optimization routing for HOS networks under traffic demand uncertainties. Gigen the number of wavelength, we first reserve several wavelengths for OBS; and then construct an OCS virtual topology; finally, using the reserved wavelengths and optimization method to achieve OBS routing. In this paper, the network performance optimization metrics is minimizing packet loss probability. Simulation results show that, in the case of a given the number of wavelength, our optimal routing method can effectively reduce packet loss probability of the whole network than that the shortest path routing; at the same time, in order to describe the uncertainty of traffic, we introduce the uncertainty factor. With the uncertainty factor decreases, the optimal routing method has less packet loss probability.

Key words: Hybrid optical switching network, packet loss probability, optimized OBS routing

摘要： 在结合了OCS和OBS优点的混合光交换网络背景下，提出了一种业务矩阵不确定的情况下的优化路由方案。在给定的波长数目下，该方案首先给OBS预留若干个波长；然后构建OCS虚拓扑；最后利用预留的波长，采用优化方法得到OBS路由。以最小化丢包率作为优化网络性能指标。仿真结果表明，在给定波长数目的情况下，与最短路由相比，采用优化路由能有效地减少整个网络的丢包率；同时，为了描述业务矩阵的不确定性，引入了不确定因子。随着不确定因子的减小，优化路由下整个网络的丢包率就越小。

关键词: 混合光交换网络, 丢失率, OBS优化路由