为了提高波分复用光网络的可靠性，常采用分段共享通路保护算法，该方法通常要求保护通路要均匀分段并且应满足共享风险链路组约束，网络业务的阻塞率也就比较高，因此提出了用优先共享通路保护算法来降低业务阻塞率。通过计算机仿真进行了理论分析和实验验证，取得了两种保护算法下的业务阻塞率和资源预留比的数据。结果表明,优先共享保护通路算法能够有效地融合分段共享通路保护算法的优点，同时在业务的阻塞率和资源预留比方面优于分段共享保护通路算法。

In order to improve the reliability of wavelength division multiplexing(WDM), the segmented shared path protection (SSPP) algorithm is usually adopted. It requires equal length segmentation in WDM optical networks and it must obey the shared risk link group (SRLG) constraint. When searching protection path, the SRLG constraint will lead the call blocking probability of the networks to rise. In order to reduce the call blocking probability, a new path protection algorithm, so-called preferential shared path protection (PSPP) was proposed. The simulation of SSPP and PSPP algorithms was done in the discrete event emulation system. The result shows the call blocking probability of the PSPP algorithm is better than that of the SSPP algorithm, and the resource reservation ratio of PSPP is also relatively better.