(RFC 4060 published May 2005, subtype last updated May 2005) Media Type name: audio Media subtype names: dsr-es202050 (for ES 202 050 front-end) dsr-es202211 (for ES 202 211 front-end) dsr-es202212 (for ES 202 212 front-end) Required parameters: none Optional parameters: rate: Indicates the sample rate of the speech. Valid values include: 8000, 11000, and 16000. If this parameter is not present, 8000 sample rate is assumed. maxptime: see RFC 3267 [7]. If this parameter is not present, maxptime is assumed to be 80ms. Note, since the performance of most speech recognizers are extremely sensitive to consecutive FP losses, if the user of the payload format expects a high packet loss ratio for the session, it MAY consider to explicitly choose a maxptime value for the session that is shorter than the default value. ptime: see RFC 2327 [5]. Encoding considerations: These types are defined for transfer via RTP [8] as described in Section 3 of RFC 4060. Security considerations: See Section 5 of RFC 4060. Person & email address to contact for further information: Qiaobing.Xie&motorola.com Intended usage: COMMON. It is expected that many VoIP applications (as well as mobile applications) will use this type. Author: Qiaobing.Xie&motorola.com Change controller: IETF Audio/Video transport working group