10 · Session border controllers
Microsoft supports Direct Routing on certified SBCs. Everything else can be refused.
The certified list is the support boundary. AudioCodes, Ribbon, Oracle, and Cisco CUBE are families you will meet. A logo is not a certification. The software release has to be on the list.
When it breaks, you call the vendor. They escalate to Microsoft if they must. Open that path with firmware, a ladder, and the paired FQDN. A homemade SBC with a clever config is an unsupported trunk.
Use a certified SBC release. Call the vendor first, with logs.
Certification is a release on Microsoft’s list. Support starts with the vendor.
If it fails: A case is opened on an unlisted SBC with no logs.
Which description of Early offer is accurate?
Teams Direct Routing presents media in the INVITE. An SBC or CUBE that waits for a delayed offer will negotiate badly. 488 and one-way audio show up when the offer model is wrong. Source: https://www.cisco.com/c/en/us/products/unified-communications/unified-border-element/index.html accessed 2026-10-14.
A colleague reports: CUCM sends delayed offer all the way to Teams. Where do you start?
CUCM sends delayed offer all the way to Teams. Set the vendor profile for early offer toward Teams. Source: https://www.cisco.com/c/en/us/products/unified-communications/unified-border-element/index.html accessed 2026-10-14.
Which description of AudioCodes is accurate?
A certified SBC family. Mediant devices and their management tools are common in Direct Routing designs. The Microsoft certified list is the support boundary, the vendor guide is the config. Naming the brand is not a design. Source: https://www.audiocodes.com/solutions-products/products/session-border-controllers accessed 2026-10-14.
Around the call: compliance recording, workforce management, emergency location, analytics, CRM screen pop, and an agent with a human escape. Each one has its own failure.
A case is opened on an unlisted SBC with no logs.
Cisco CUBE is one of the SBC families named in this lab’s certification lesson. A certified release can be the Direct Routing SBC between Unified CM and Teams.
The tenant still needs a verified domain on the SBC FQDN, and the user still needs Teams Phone. The studio translator does not open a live AXL session. Confirm the current certified release before you build.
Teams Phone and Webex Calling are separate clouds. This lab does not describe a feature that registers a Webex Calling user into a Teams tenant.
A number move is usually a carrier port, a certified SBC, or a meetings interop product. Confirm before relying.
Unified CCE stays the ACD until you migrate it. Microsoft’s contact-center articles name Connect, Extend, and Unify. They do not name a UCCE connector in the notes this lab cites.
Voice into Teams is still Direct Routing or Operator Connect. The routing script stays on the contact-center product you bought. Confirm the vendor’s current model. Source: https://learn.microsoft.com/en-us/microsoftteams/teams-contact-center.
Copilot Studio, Azure Communication Services, and Graph are later tracks in this lab. Treat any uncited limit as confirm before relying.
Opened 2026-10. A row marked confirm did not open. Wikipedia is background. The Teams blog row is the community index.
