10 · Session border controllers
CUBE is the usual bridge when CUCM is still in the building. It is still an SBC.
Cisco Unified Border Element on a certified IOS-XE release peers TLS with the three commercial proxies, presents a certificate whose SAN matches the paired FQDN, and has dial-peers toward Teams and toward CUCM or the carrier. Teams expects early offer. A delayed-offer trunk from CUCM pushed all the way to Teams negotiates badly.
This campus does not paste a production dial-peer. Use Cisco’s current CUBE for Teams guide for the release you run. Trust the published signaling ranges rather than a single DNS answer. Offer a codec both sides share, G.711 at minimum unless you have a measured reason not to.
Use a certified CUBE release, early offer toward Teams, and a certificate name that matches the paired FQDN.
CUBE is a certified SBC with dial-peers in two directions and early offer toward Teams.
If it fails: CUCM sends delayed offer all the way to Teams and calls fail with 488.
Which description of Certified list changes is accurate?
The list of SBCs and contact-center solutions changes. A campus page is not the list. Quote the list the week you buy. Source: https://learn.microsoft.com/en-us/microsoftteams/direct-routing-border-controllers accessed 2026-10-14.
A colleague reports: A purchase order cites a 2022 PDF. Where do you start?
A purchase order cites a 2022 PDF. Link the design to the current Microsoft page and the firmware. Source: https://learn.microsoft.com/en-us/microsoftteams/direct-routing-border-controllers accessed 2026-10-14.
Which description of Session border controller is accurate?
The device that speaks SIP to Teams and SIP or another protocol to the carrier or PBX, and enforces the edge. Without a certified one, Direct Routing is unsupported. Source: https://learn.microsoft.com/en-us/microsoftteams/direct-routing-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.
CUCM sends delayed offer all the way to Teams and calls fail with 488.
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.
