Source note · SDP offer answer and codec negotiation
Holding a call by setting the connection address to 0.0.0.0 is no longer recommended because it prevents RTCP on held streams, does not work with IPv6 and breaks connection oriented media, but an agent must still be capable of receiving an SDP with that address.
Checked 2026-09-15
An agent MUST be capable of receiving SDP with a connection address of 0.0.0.0, in which case it means that neither RTP nor RTCP should be sent to the peer.
- Vendor
- IETF
- Product
- SIP
- Subsystem
- SDP offer/answer
- Deployment
- not restricted
- Region
- not restricted
- Release range
- RFC 3264
- Checked
- 2026-09-15
Sources
- RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) — IETF / RFC Editor · tier 1 standards and regulators · RFC 3264 section 8.4 Putting a Unicast Media Stream on Hold
Cite this note
APA
WarmTransfer. (2026, September 15). SDP offer answer and codec negotiation: source note sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted. WarmTransfer. https://warmtransfer.net/knowledge/claims/sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted
BibTeX
@misc{warmtransfer-claim-sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted,
title = {SDP offer answer and codec negotiation: source note sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted},
note = {Source note sdp-oa-zero-address-hold-is-deprecated-but-must-be-accepted, checked 2026-09-15}
}