http://www.rfc-editor.org/rfc/rfc3773.txt
RFC 3773: High-Level Requirements for Internet Voice Mail, E. Candell2004-06-01T23:00:00-00:00This document describes the high-level requirements for Internet Voice Mail (IVM) and establishes a baseline of desired functionality against which proposed MIME profiles for Internet Voice Messaging can be judged. IVM is an extension of the Voice Profile for Internet Mail (VPIM) version 2 designed to support interoperability with desktop clients. Other goals for this version of VPIM include expanded interoperability with unified messaging systems, conformance to Internet standards, and backward compatibility with voice messaging systems currently running in a VPIM enabled environment. This document does not include goals that were met fully by VPIM version 2. This memo provides information for the Internet community.