Zoom calls from Room kits that are registered to CUCM via SIP

[Yarin Ezra]

Hello everyone,

I'd like to know if there's a way to register a room kit such as: Webex room kit mini, Webex Room kit Plus, TP SX20, SX10, etc....

to CUCM Server using SIP and call from endpoint to Zoom or Webex calls.

Today, i have a customer that register the endpoints to Expressway C/E using H323 and make the calls to Zoom/Webex using Macros.

it works perfectly fine but i'd like to suggest him to switch to SIP using CUCM.

[Jonathan Schulenberg]

Yes. The endpoints can register to CUCM which then uses Expressway Business to Bysiness (B2B) calling to traverse the corporate firewall and public internet. That part is likely already deployed if they’re registered to Expressway now; you probably just need a Neighbor Zone for CUCM and SIP Trunk on CUCM with SIP Route Patterns.

Check out the Expressway Config Guides, specifically the Basic Config Deployment Guide and the CUCM via SIP Trunk Deployment Guide.

Specific to Webex Meetings, you should also configure Active Control / iX Media; or, use Webex Edge for Devices with Optimized Join Experience. The latter is the recommended approach for customers sticking with on-prem call control - either CUCM or Expressway registration.

[Yarin Ezra]

There's already a zone to CUCM and it works as expected but i needed to know what to put in the SIP Route pattern.

right now, i configured the endpoints with an API button to dial to a H323 Zoom IP, after that the customer types in the endpoint a room number and than connect to the conference.

so if may i ask, how do i configure the SIP Route pattern to point it to the Expressway

[Jonathan Schulenberg]

Nearly identical to a numeric Route Pattern except for the pattern itself. You have to choose IPv4 or DNS domain. For the latter, a simple default/catch-all is "*". See Configure URI Dialing for more info.

Just be mindful that CUCM does not support direct IP dialing; everything must be a URI (e.g. foo@192.0.2.1). If you need actual direct IP dialing you will need to retrain users to use a URI. Expressway-C can use a Transform rule to convert the URI back to direct IP. For example, if users will dial ip@192.0.2.1 the Expressway Transform would be ip@(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}) with a replace behavior and replace value of \1.