—Providing differentiated Quality-of-Protection (QoP) for surviving single-link failures in WDM mesh networks has been extensively studied in recent years. This paper investigates the problem of providing differentiated QoP for surviving arbitrary double-link failures by allowing a connection request to choose from several QoP classes. In this paper, we propose to use three classes, i.e., single shared-path protection (SSPP), single dedicated-path protection (SDPP), and double shared-path protection (DSPP) to provide differentiated QoP. We present two differentiated QoP schemes. Scheme 1 (conventional differentiated QoP) is a natural extension of conventional differentiated QoP for surviving single-link failures, which uses SDPP, SSPP, and SDPP separately to satisfy different QoP requirements. Scheme 2 (shared differentiated QoP) tries to share backup resources between SSPP and SDPP. Simulation results show that our proposed architecture of QoP can satisfy different QoP requirements ...