http://www.rfc-editor.org/rfc/rfc2245.txt
RFC 2245: Anonymous SASL Mechanism, C. Newman1997-11-01T23:00:00-00:00As plaintext login commands are not permitted in new IETF protocols, a new way to provide anonymous login is needed within the context of the SASL [SASL] framework. [STANDARDS-TRACK]