The Full-Standard Real-time Transport Protocol, RTP [RFC 3550], along 
  with its associated profiles and payload formats provides for real-
  time transmission of audio and video over unicast and multicast 
  transports. RTP is widely implemented, and deployed for a wide range 
  of applications, ranging from telephony to television over IP. As new 
  applications have emerged, the need for guidelines for the use of the 
  RTP/RTCP protocols and extensions specific to those applications 
  has been identified.
  
  The AVTEXT working group is charted to develop application-specific 
  guidelines for the use of RTP/RTCP protocols with the AVP, SAVP, 
  AVPF, and SAVPF profiles, and extensions to those protocols that are 
  driven by application-specific needs. Proposals for extensions with 
  general applicability to many different RTP/RTCP usages should be 
  taken to the AVTCORE working group. 
  
  The AVTEXT working group is constrained to use the protocol extension 
  mechanisms defined in the core protocols (such as RTP Header 
  extensions [RFC5285], AVPF Feedback Messages [RFC4585], and 
  SDES Items [RFC3550]). If new ways to extend the core protocols are 
  needed, they will be developed in the AVTCORE working group.
  
  In addition to the milestones called out below, the AVTEXT working 
  group's initial tasks will include completing any new work identified 
  during IESG evaluation for the Rapid Acquisition of Multicast RTP 
  Sessions.