1前言近几年来,Internet的迅猛发展和数据业务的快速增长极大地推动了电信传送网络向多业务和高带宽的方向发展。为了保证业务的正常提供,网络生存性的问题显得越来越重要。而多层传输网络中不同网络技术的集成(如IP和OTN),给多层网络的生存性带来了机遇和挑战。主要表现在多层网络中,不同网络层间的可 1 Introduction In recent years, the rapid development of the Internet and the rapid growth of data services has greatly promoted the telecom transport network to multi-service and high-bandwidth direction. In order to ensure the normal provision of services, the issue of network survivability becomes more and more important. The integration of different network technologies (such as IP and OTN) in multi-layer transport networks brings opportunities and challenges to the survivability of multi-layer networks. Mainly in the multi-layer network, the network layer can be