(RFC 3389 published September 2002, subtype last updated September 2002) MIME media type name: audio MIME subtype name: CN Required parameters: None Optional parameters: rate: specifies the RTP timestamp clock rate, which is usually (but not always) equal to the sampling rate. This parameter should have the same value as the codec used in conjunction with comfort noise. The default value is 8000. Encoding considerations: This type is only defined for transfer via RTP [RFC 1889]. Security considerations: see Section 7 "Security Considerations". Interoperability considerations: none Published specification: This document and Appendix II of ITU-T Recommendation G.711 Applications which use this media type: Audio and video streaming and conferencing tools. Additional information: none Person & email address to contact for further information: Robert Zopf zopf&lucent.com Intended usage: COMMON Author/Change controller: Author: Robert Zopf Change controller: IETF AVT Working Group