Before deploying Call Manager to a customer, it is helpful to verify the following are in-place:
Licenses
Each user that will be using phone services in the customer tenant should have a Microsoft Phone System license assigned. This can be a stand-alone 'Phone System' license or part of a license bundle such as Office 365 E5
Phone Numbers
Using Operator Connect, Direct Routing or Calling Plans, provision the number ranges for the customer into the Teams tenant.
Administrator Access
The invitation for the customer to grant permissions to Call Manager needs to be accepted by a user with sufficient Microsoft 365 administrative rights. Many customers use a Global Administrator for convenience, while others may have policies to use a user with only the minimum required permission.
Using time-limited elevation via Privileged Identity Management (PIM) is appropriate for this one-time consent step. After setup is complete, the Call Manager app operates with a lower level of privilege.
Minimum required roles for the consenting user:
- Teams Administrator
- Privileged Role Administrator
SSO Access for Call Manager
Call Flow Plans
Have a plan for mapping how incoming numbers are to be distributed around the customer, document group membership, group ringing patterns, open hours, user DDI mapping etc.