RFC 3966 identifies globally unique telephone numbers by a leading plus and requires them to be composed of country code and national number per E.164.
Checked 2026-10-02
- Vendor
- not restricted
- Product
- not restricted
- Subsystem
- Telephone number URIs
- Deployment
- any
- Region
- not restricted
- Release range
- RFC 3966 as published
- Checked
- 2026-10-02
Sources
- RFC 3966: The tel URI for Telephone Numbers — IETF / RFC Editor · tier 1 standards and regulators · Section 5.1.4 (Global Numbers)
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting SIP 404 Not Found and 484 Address Incomplete call failures: source note sip-404-484-troubleshooting-rfc3966-global-plus. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-404-484-troubleshooting-rfc3966-global-plus
BibTeX
@misc{warmtransfer-claim-sip-404-484-troubleshooting-rfc3966-global-plus,
title = {Troubleshooting SIP 404 Not Found and 484 Address Incomplete call failures: source note sip-404-484-troubleshooting-rfc3966-global-plus},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-404-484-troubleshooting-rfc3966-global-plus},
note = {Source note sip-404-484-troubleshooting-rfc3966-global-plus, checked 2026-10-02}
}