http://www.rfc-editor.org/rfc/rfc4842.txt
RFC 4842: Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) Circuit Emulation over Packet (CEP), A. Malis, P. Pate, R. Cohen, D. Zelig2007-04-01T23:00:00-00:00This document provides encapsulation formats and semantics for emulating Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) circuits and services over MPLS. [STANDARDS-TRACK]