When BypassMode is defined, Direct Routing adds X-MS-UserLocation (internal or external), X-MS-MediaPath (the ordered SBC list for the media path, with the final SBC always last) and X-MS-UserSite (the tenant administrator's site string) to SIP INVITEs and re-INVITEs, and the Request-URI targets the SBC FQDN.

Checked 2026-09-16

X-MS-UserLocation | internal/external | Indicates if user is internal or external
Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
Local Media Optimization signalling
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-16
Checked
2026-09-16

Sources

Cite this note

APA

WarmTransfer. (2026, September 16). CUCM to Teams Phone migration: source note cucm-to-teams-phone-lmo-xms-headers. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-to-teams-phone-lmo-xms-headers

BibTeX

@misc{warmtransfer-claim-cucm-to-teams-phone-lmo-xms-headers,
  title  = {CUCM to Teams Phone migration: source note cucm-to-teams-phone-lmo-xms-headers},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-to-teams-phone-lmo-xms-headers},
  note   = {Source note cucm-to-teams-phone-lmo-xms-headers, checked 2026-09-16}
}

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