Definition of Events for Modem, Fax, and Text Telephony Signals

This specification has been revised 2 times since RFC 2833 (2000). Each document below formally obsoleted the one before it; the versions still in force are listed first.

This lineage is derived automatically from the “obsoletes” relationships recorded in the public RFC Editor index — no editorial judgement is applied to the ordering. The most recent document in the chain is RFC 4734 (December 2006).