Source note · Moving from Unified CM to Zoom Phone
On calls into Zoom, Zoom supports PRACK for early media but does not use SIP preconditions or the Replaces header.
Checked 2026-09-25
Zoom supports the PRACK mechanism for Early Media but does not use SIP preconditions or the Replaces header for redirection.
- Vendor
- Zoom
- Product
- Zoom Phone
- Subsystem
- SIP call processing
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-25
- Checked
- 2026-09-25
Sources
- BYOC-P or BYOP-P call processing — Zoom Communications · tier 2 current vendor documentation · Incoming calls to Zoom section
Cite this note
APA
WarmTransfer. (2026, September 25). Moving from Unified CM to Zoom Phone: source note cucm-to-zoom-phone-no-replaces. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-to-zoom-phone-no-replaces
BibTeX
@misc{warmtransfer-claim-cucm-to-zoom-phone-no-replaces,
title = {Moving from Unified CM to Zoom Phone: source note cucm-to-zoom-phone-no-replaces},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-to-zoom-phone-no-replaces},
note = {Source note cucm-to-zoom-phone-no-replaces, checked 2026-09-25}
}