Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) Circuit Emulation Service over MPLS (CEM) Encapsulation

This document describes a historical method for encapsulating Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) Path signals for transport across packet-switched networks (PSNs). The PSNs explicitly supported by this document include MPLS and IP. Note that RFC 4842 describes the standards-track protocol for this functionality, and new implementations must use RFC 4842 rather than this document except when interoperability with older implementations is desired. This memo defines a Historic Document for the Internet community.