GMPLS [1] provides ideally a robust and flexible control plane protocols set designed for application over generalized transport network. A typical application of GMPLS is, among others, the control of transport networks based on SDH/SONET [2] technology. In this scenario, the introduction of GMPLS based control plane should ensure support of and/or compatibility with the most important and widely exploited SDH/SONET features, making possible a seamless interworking with inherent data plane requirements. In this document we focus on one of the most attractive SDH/SONET protection mechanism, implemented through MS-SPRing (G.841 [3]), a widely deployed ITU standard for ring-shared protection.