(RFC 5577 published July 2009) Media type name: audio Media subtype name: G7221 Required parameters: bitrate: the data rate for the audio bit stream. This parameter is mandatory because the bit rate is not signaled within the G.722.1 bit stream. At the standard G.722.1 bit rates, the value MUST be either 24000 or 32000 at 16 Khz sample rate, and 24000, 32000, or 48000 at 32 Khz sample rate. If using the non-standard bit rates, then it is RECOMMENDED that values in the range 16000 to 48000 be used. Non-standard rates MUST have a value that is a multiple of 400 (this maintains octet alignment and does not then require (undefined) padding bits for each frame if not octet aligned). Optional parameters: rate: RTP timestamp clock rate, which is equal to the sampling rate. If the parameter is not specified, a clock rate of 16 Khz is assumed. ptime: see RFC 8866. SHOULD be a multiple of 20 ms. maxptime: see RFC 8866. SHOULD be a multiple of 20 ms. Encoding considerations: This media type is framed and binary, see Section 4.8 in [RFC4288]. Security considerations: See Section 6 Interoperability considerations: Terminals SHOULD offer a media type at 16 Khz sample rate in order to interoperate with terminals that do not support the new 32 Khz sample rate. Published specification: RFC 5577. Applications that use this media type: Audio and Video streaming and conferencing applications. Additional information: none Person and email address to contact for further information : Roni Even: ron.even.tlv&gmail.com Intended usage: COMMON Restrictions on usage: This media type depends on RTP framing, and hence is only defined for transfer via RTP [RFC3550]. Transport within other framing protocols is not defined at this time. Author: Roni Even Change controller: IETF Audio/Video Transport working group delegated from the IESG.