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CUCM, a certified SBC, and Teams Direct Routing

CUBE or another certified SBC can sit between CUCM and Teams. No architecture SKU is invented here.

Learn in 5 minutes

  1. Place a certified SBC between CUCM and Teams
  2. Require TLS 1.2+ and an FQDN Contact
  3. Keep the SIP target on sip.pstnhub.microsoft.com

Visual

CUCM to CUBE to Teams · study drawing · cyphermonkeylabs.com CUCMCUBETeams INVITE 100 INVITE 100 OPTIONS

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Certified means the SBC Microsoft lists for Direct Routing. This lesson names no SKU.

Worked example

Read Contact on the Teams INVITE What does Contact contain on the hop toward Teams?

  1. Press Play.
  2. Step until the hop named in the question.
  3. Inspect that message and answer the check.

Fault

INVITE to sip.pstnhub.microsoft.com uses Contact sip:203.0.113.20 and the ticket adds a router SKU as the fix. TLS 1.2 already succeeded.

403 after a good handshake is the Contact rule. The plan page does not ask you to invent a platform SKU.

Quiz

Between CUCM and Teams Direct Routing this lesson places


The Teams SIP target used here is


TLS toward Teams is


Contact toward Teams must be


A certificate name mismatch


CUCM's address in this lab path is


Ecosystem

Glossary, sister systems, and the integration seam for this room.

AI omni-channel agents A voice bot still needs a session. SIP creates, modifies, and ends sessions. Omni-channel, in the contact-center sense, means the same contact can also live on chat or another digital channel. Those channels do not replace the voice session. On Amazon Connect the platform owns the managed PSTN voice channel. Bridging an outside carrier into Connect with a Chime Voice Connector is not a supported pattern unless AWS reviews it. When an SBC forks the voice leg to a recorder, that fork is SIPREC, a different plane from the customer dialog.

AI agents A voice bot still needs a session. On Amazon Connect the platform owns the managed PSTN voice channel. Bridging an outside carrier into Connect with a Chime Voice Connector is not a supported pattern unless AWS reviews it. The FreeSWITCH manual page also describes SignalWire, founded by the FreeSWITCH team, as a hosted platform with AI agents behind REST APIs and SWML.

Glossary · Ecosystem map · Ports · Troubleshooting

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