Source note · Zoom Phone routing and PSTN connectivity
Inbound INVITEs from the SBC to Zoom must carry an SDP offer (early offer); otherwise Zoom answers 488 Not Acceptable Here.
Checked 2026-09-24
- Vendor
- Zoom
- Product
- Zoom Phone; Zoom Contact Center
- Subsystem
- byoc-p-sip
- Deployment
- hybrid
- Region
- not restricted
- Release range
- current as of 2026-09-24
- Checked
- 2026-09-24
Sources
- BYOC-P or BYOP-P call processing — Zoom Communications · tier 2 current vendor documentation · Incoming calls to Zoom
Cite this note
APA
WarmTransfer. (2026, September 24). Zoom Phone routing and PSTN connectivity: source note zoom-phone-routing-inbound-early-offer-488. WarmTransfer. https://warmtransfer.net/knowledge/claims/zoom-phone-routing-inbound-early-offer-488
BibTeX
@misc{warmtransfer-claim-zoom-phone-routing-inbound-early-offer-488,
title = {Zoom Phone routing and PSTN connectivity: source note zoom-phone-routing-inbound-early-offer-488},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/zoom-phone-routing-inbound-early-offer-488},
note = {Source note zoom-phone-routing-inbound-early-offer-488, checked 2026-09-24}
}