Source note · DNS SRV and service discovery for SIP
Under RFC 3263, if no SRV records are found the client performs an A or AAAA lookup of the domain name and contacts it at the default port for the selected transport.
Checked 2026-09-24
- Vendor
- IETF
- Product
- SIP
- Subsystem
- server location
- Deployment
- any
- Region
- not restricted
- Release range
- RFC 3263 (June 2002)
- Checked
- 2026-09-24
Sources
- RFC 3263: Session Initiation Protocol (SIP): Locating SIP Servers — RFC Editor / IETF · tier 1 standards and regulators · Section 4.2 Determining Port and IP Address
Cite this note
APA
WarmTransfer. (2026, September 24). DNS SRV and service discovery for SIP: source note dns-srv-voice-rfc3263-no-srv-default-port. WarmTransfer. https://warmtransfer.net/knowledge/claims/dns-srv-voice-rfc3263-no-srv-default-port
BibTeX
@misc{warmtransfer-claim-dns-srv-voice-rfc3263-no-srv-default-port,
title = {DNS SRV and service discovery for SIP: source note dns-srv-voice-rfc3263-no-srv-default-port},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/dns-srv-voice-rfc3263-no-srv-default-port},
note = {Source note dns-srv-voice-rfc3263-no-srv-default-port, checked 2026-09-24}
}