14 Coexistence and CCaaS
Pro tips
• Connect, Extend, and Unify are different media paths. Name the model before you name the product.
• CUCM to Teams through Direct Routing is a certified SBC, often CUBE, with one owner for normalization.
• Webex, UCCE, Genesys, and Amazon Connect each need a named bridge. 'We integrate' is not a design.
Interview traps
• Mapping a CUCM calling search space onto a Teams dial plan as if the objects were the same.
• Letting both CUCM and Teams rewrite the same number.
Cheat sheet
Connect SBC between the PBX and Teams
Extend Graph and the client; media stays put
Unify ACS-native contact-center path
CUCM partition, CSS, route pattern
Teams dial plan, usage, route, gateway
One system owns normalization
Facts in the long lessons were checked 14 October 2026. This sheet is a memory aid.