As the Internet and network technologies evolve, the IP over WDM solution has been envisioned as the most promising solution for the next generation Internet architecture. So survivability in IP/WDM networks becomes critical for the success of the next generation Internet architecture. Considerable research efforts have been dedicated to studying the survivability in IP/GMPLS and WDM network respectively, but still remains the need for a better understanding of the interworking, coordination and functionality partitioning in survivability between IP and WDM. In this paper, we explore the necessity, methods and advantages to coordinate multi-layer survivability in IP/WDM network. We especially focus on the study of the escalation method, multi-layer network spare capacity design and function partitioning. We study the use of differentiated survivability policies combined with a multi-layer survivability scheme for IP/WDM networks. Keywords Differentiated multi-layer IP/WDM protection, ...