WebRTC implementations MUST support multiplexing of DTLS and RTP over
the same port pair, as described in the DTLS-SRTP specification
[RFC5764], section 5.1.2. All application layer protocol payloads
over this DTLS connection are SCTP packets.
That document is publication requested so even as normative reference it will hopefully have minimal impact on the publication progress of this document.
From Magnus Westerlund in IETF LC:
Section 3.5:
WebRTC implementations MUST support multiplexing of DTLS and RTP over the same port pair, as described in the DTLS-SRTP specification [RFC5764], section 5.1.2. All application layer protocol payloads over this DTLS connection are SCTP packets.
This text should reference also the update to RFC5764: https://datatracker.ietf.org/doc/draft-ietf-avtcore-rfc5764-mux-fixes/
That document is publication requested so even as normative reference it will hopefully have minimal impact on the publication progress of this document.