Source note · SIP early offer and delayed offer
For 46 Labs' carriers to send a reliable 18x on a delayed-offer call, the INVITE must include 100rel in the Supported or Require header.
Checked 2026-09-25
SIP Invite must contain the value 100rel in the Supported or Require headers
- Vendor
- 46 Labs
- Product
- 46 Labs SIP carrier services
- Subsystem
- carrier-interconnect
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-25
- Checked
- 2026-09-25
Sources
- Early Offer versus Delayed Offer SIP Invites — 46 Labs · tier 2 current vendor documentation · Article body, 100rel paragraph
Cite this note
APA
WarmTransfer. (2026, September 25). SIP early offer and delayed offer: source note sip-early-delayed-offer-46labs-100rel-required. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-early-delayed-offer-46labs-100rel-required
BibTeX
@misc{warmtransfer-claim-sip-early-delayed-offer-46labs-100rel-required,
title = {SIP early offer and delayed offer: source note sip-early-delayed-offer-46labs-100rel-required},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-early-delayed-offer-46labs-100rel-required},
note = {Source note sip-early-delayed-offer-46labs-100rel-required, checked 2026-09-25}
}