Source note · SIP registration failures
A client may add an rport parameter with no value to the top Via, and when it sends over UDP it must be ready to receive the response on the same IP address and port it sent from.
Checked 2026-09-25
- Vendor
- not restricted
- Product
- SIP
- Subsystem
- nat-traversal
- Deployment
- any
- Region
- not restricted
- Release range
- RFC 3581
- Checked
- 2026-09-25
Sources
- RFC 3581: An Extension to the Session Initiation Protocol (SIP) for Symmetric Response Routing — IETF / RFC Editor · tier 1 standards and regulators · Section 3 Client Behavior
Cite this note
APA
WarmTransfer. (2026, September 25). SIP registration failures: source note sip-registration-failures-rport-client. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-registration-failures-rport-client
BibTeX
@misc{warmtransfer-claim-sip-registration-failures-rport-client,
title = {SIP registration failures: source note sip-registration-failures-rport-client},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-registration-failures-rport-client},
note = {Source note sip-registration-failures-rport-client, checked 2026-09-25}
}