http://www.rfc-editor.org/rfc/rfc6064.txt
RFC 6064: SDP and RTSP Extensions Defined for 3GPP Packet-Switched Streaming Service and Multimedia Broadcast/Multicast Service, M. Westerlund, P. Frojdh2011-01-01T23:00:00-00:00The Packet-switched Streaming Service (PSS) and the Multimedia Broadcast/Multicast Service (MBMS) defined by 3GPP use the Session Description Protocol (SDP) and Real Time Streaming Protocol (RTSP) with some extensions. This document provides information about these extensions and registers the RTSP and SDP extensions with IANA. This document is not an Internet Standards Track specification; it is published for informational purposes.