http://www.rfc-editor.org/rfc/rfc1340.txt
RFC 1340: Assigned Numbers, J. Reynolds, J. Postel1992-07-01T23:00:00-00:00This Network Working Group Request for Comments documents the currently assigned values from several series of numbers used in network protocol implementations. This memo is a status report on the parameters (i.e., numbers and keywords) used in protocols in the Internet community.