Microsoft Teams offers three options to add Public Switched Telephone Network (PSTN) connectivity: Calling Plans, Direct Routing, and Operator Connect. Operator Connect is a Bring Your Own Carrier solution with Software-Defined Branch (SBC)-as-a-service that allows organizations to add PSTN connectivity from the Microsoft Teams Admin Center using third-party carriers or "operators." It offers benefits such as user-friendly telephony management, pure cloud deployment, unified communications, higher quality calling experiences, and better support. To deploy Operator Connect, you need a Microsoft Teams License that includes Phone Systems, activated TeamsOnly mode, a Microsoft-certified Operator (SIP provider), and a Microsoft-certified E911 Provider.