http://www.rfc-editor.org/rfc/rfc4446.txt
RFC 4446: IANA Allocations for Pseudowire Edge to Edge Emulation (PWE3), L. Martini2006-04-01T23:00:00-00:00This document allocates the fixed pseudowire identifier and other fixed protocol values for protocols that have been defined in the Pseudo Wire Edge to Edge (PWE3) working group. Detailed IANA allocation instructions are also included in this document. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.