Name,Description,Reference
play.basic,"The implementation for delivery and playback operations
         according to the core RTSP specification, as defined in this
         memo. Applies for clients, servers, and proxies. See
         Section 11.1 of [RFC7826]",[RFC7826]
play.scale,"Support of scale operations for media playback. Applies
         only for servers. See Section 18.46 of [RFC7826].",[RFC7826]
play.speed,"Support of the speed functionality for media delivery.
        Applies only for servers.  See Section 18.50 of [RFC7826].",[RFC7826]
setup.rtp.rtcp.mux,"Support of the RTP and RTCP multiplexing as
        discussed in Appendix C.1.6.4 of [RFC7826]. Applies for both client and
         servers and any media caching proxy.",[RFC7826]
setup.ice-d-m,"A feature tag representing the support of the ICE-based 
establishment of datagram media transport that is capable of
transport establishment through NAT and firewalls. This feature
tag applies to clients, servers, and proxies and indicates support
of all the mandatory functions of this specification.",[RFC7825]