For Direct Routing the SBC must support SRTP cipher AES_CM_128_HMAC_SHA1_80 in both offer and answer using the inline key||salt format with optional lifetime.

Checked 2026-09-25

Vendor
Microsoft
Product
Teams Phone Direct Routing
Subsystem
SRTP
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 488 and codec negotiation failures: source note sip-488-codec-failures-teams-srtp-cipher. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-teams-srtp-cipher

BibTeX

@misc{warmtransfer-claim-sip-488-codec-failures-teams-srtp-cipher,
  title  = {SIP 488 and codec negotiation failures: source note sip-488-codec-failures-teams-srtp-cipher},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-teams-srtp-cipher},
  note   = {Source note sip-488-codec-failures-teams-srtp-cipher, checked 2026-09-25}
}

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