The RFC 4694 'npdi' tel URI parameter tells downstream servers or switches that a number portability database dip has already been performed for the number.
Checked 2026-10-02
- Vendor
- not restricted
- Product
- not restricted
- Subsystem
- sip-signalling
- Deployment
- sip
- Region
- not restricted
- Release range
- RFC 4694
- Checked
- 2026-10-02
Sources
- RFC 4694: Number Portability Parameters for the "tel" URI — IETF / RFC Editor · tier 1 standards and regulators · RFC 4694 Section 1
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting calls that fail to ported numbers after cutover: source note post-port-routing-troubleshooting-rfc4694-npdi-meaning. WarmTransfer. https://warmtransfer.net/knowledge/claims/post-port-routing-troubleshooting-rfc4694-npdi-meaning
BibTeX
@misc{warmtransfer-claim-post-port-routing-troubleshooting-rfc4694-npdi-meaning,
title = {Troubleshooting calls that fail to ported numbers after cutover: source note post-port-routing-troubleshooting-rfc4694-npdi-meaning},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/post-port-routing-troubleshooting-rfc4694-npdi-meaning},
note = {Source note post-port-routing-troubleshooting-rfc4694-npdi-meaning, checked 2026-10-02}
}