Explanation/Reference:
Explanation: The Session Description Protocol (SDP), defined in RFC 2327, describes the content of sessions, including telephony, Internet radio, and multimedia applications. SDP includes information about
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Media streams: A session can include multiple streams of differing content. SDP currently defines audio, video, data, control, and application as stream types, similar to the MIME types used for Internet mail.

Addresses: SDP indicates the destination addresses, which may be a multicast address, for a media stream.

Ports: For each stream, the UDP port numbers for sending and receiving are specified.

Payload types: For each media stream type in use (for example, telephony), the payload type indicates the media formats that can be used during the session.

Start and stop times: These apply to broadcast sessions, for example, a television or radio program. The start, stop, and repeat times of the session are indicated.

Originator: For broadcast sessions, the originator is specified, with contact information. This may be useful if a receiver encounters technical difficulties.