Direct Routing SIP signaling FQDNs for Microsoft 365, Office 365 and GCC resolve to 52.112.0.0/14 and 52.120.0.0/14, and to 2603:1063:400::/40 for IPv6.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
SIP signaling
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP scanning and telephony denial of service: source note sip-scanning-tdos-ms-dr-signaling-ranges. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-scanning-tdos-ms-dr-signaling-ranges

BibTeX

@misc{warmtransfer-claim-sip-scanning-tdos-ms-dr-signaling-ranges,
  title  = {SIP scanning and telephony denial of service: source note sip-scanning-tdos-ms-dr-signaling-ranges},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-scanning-tdos-ms-dr-signaling-ranges},
  note   = {Source note sip-scanning-tdos-ms-dr-signaling-ranges, checked 2026-09-25}
}

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