What is an SBC for Microsoft Teams and Why It Matters

Microsoft Teams has become much more than a messaging and collaboration app. For many organizations, it’s evolving into a complete business phone system.

While internal chat and collaboration are its core, organizations quickly discover that for external calling to the Public Switched Telephone Network (PSTN), Teams licenses alone are insufficient.

That’s where Direct Routing comes in, and at the heart of that setup is the Session Border Controller (SBC).

SBCs for Teams serve as an important bridge between the MS Teams account and your telephony provider, enabling secure, high-quality external calls. Without them, your Microsoft Teams environment falls short on flexibility, control, and the global connectivity required for high-performance voice.

SBCs are a must if your company wants to improve communications, reduce telecom expenses, and take complete control of call routing.

Let’s delve into what a Direct Routing SBC is and precisely how they function within the architecture of cloud telephony, particularly in the context of Microsoft Teams Direct Routing.

In this article, we’ll cover:

• What is an SBC
• Overview of MS Teams Direct Routing
• How SBCs Enable Teams Direct Routing
• Benefits of Using an SBC for Teams Direct Routing
• Direct Routing vs Operator Connect vs Calling Plans
• Where United World Telecom Can Help

What is an SBC?

Acting as a guardian for VoIP communications, it ensures security, interoperability, and high-quality voice and video calls. Think of it as the “firewall and traffic controller” for your VoIP system.

It plays a very important role in:

• Call Quality (VoIP QoS) – By managing network traffic and constraining data rates, SBCs contribute significantly to maintaining exceptional call quality (Quality of Service or QoS) across VoIP networks.

• Security – SBCs work as a vital barrier against eavesdropping, illegal access, and other cyber threats like Denial of Service or DoS attacks. It supports media encryption, enforces security regulations, and offers strong access control to protect private conversations.

• Compliance – They also assist organizations in meeting regulatory compliance requirements through features such as call recording, call monitoring, and call logging.

Quick Overview of Microsoft Teams Direct Routing

Microsoft Teams Direct Routing is a flexible solution that lets you connect MS Teams to the PSTN using your preferred telecom provider.

Instead of relying solely on Microsoft Calling Plans, you can bring your own carrier and route calls through your own SIP trunk provider—giving you greater control over costs, call quality, and global coverage.

An SBC is mandatory for this setup as it securely connects your SIP trunks to Microsoft Teams, ensuring smooth call flow, compatibility, and high-quality voice calls.

Together, they allow Teams users to make and receive external calls—just like with a traditional phone system, but over the internet. It’s a cost-effective and flexible solution for businesses wishing to use Teams as a complete phone system.

Learn more in our guide to Teams Direct Routing.

How SBCs Enable Teams Direct Routing

An SBC for Teams sits as a key component between MS Teams and your preferred carrier.

Here are the key functions of Direct Routing SBCs:

• Enabling SIP Trunking (Global Voice Integration) – SBCs allow Microsoft Teams to connect to SIP trunk providers globally. This flexible BYOC solution gives businesses more control over call costs and access global phone number coverage—while using MS Teams as their main communication platform.

• Advanced Routing Logic and Number Management – Direct Routing SBCs also give you access to advanced routing capabilities. You can configure routing rules based on various measures (e.g., user location, time of day), ensuring calls reach the right destination without any hassle. They also manage number formats and dial plans, ensuring that outbound and inbound calls are properly routed.

• International Caller ID Compatibility – SBCs can manage and maintain caller ID information across regions, ensuring that outbound calls from Teams display the correct international caller ID and inbound calls display the caller’s identity accurately.

• Normalizing Codecs and SIP Signaling – Different communication systems use different codecs (for audio compression) and SIP signaling protocols. An SBC for Teams translates and standardizes these protocols, allowing compatibility between Teams and external carriers for efficient call setup and call quality.

Benefits of Using an SBC with Direct Routing

An SBC for Teams Direct Routing unlocks multiple advantages beyond simply connecting calls. From lowering costs to ensuring security and supporting global scalability, an SBC adds the control and flexibility enterprises need to make Microsoft Teams a reliable telephony platform.

• Lower Costs for Global Calling – Reduce international and high-volume call costs by using your own SIP trunks instead of Microsoft’s per-minute Calling Plans.

• Greater Flexibility – Direct Routing SBCs offer greater flexibility than Operator Connect or Calling Plans by allowing you to connect with almost any SIP trunk provider worldwide. You can choose carriers based on cost, global coverage, or existing contracts to suit your specific needs.

• Hybrid & Legacy PBX Support – Use an SBC for Teams to keep existing PBX infrastructure while gradually migrating to Teams.

• Advanced Telephony Features – By integrating your desired telephony provider with MS Teams, your Teams users can access advanced features like smart call routing, IVR, call recording, outbound caller ID, and more.

• Smart Call Handling – High-call-volume businesses can use Direct Routing SBCs and advanced telephony features to prioritize call quality and routing control.

• Connect Global Teams with Local Numbers – Companies that operate globally can utilize international SIP trunks to offer local phone numbers worldwide. Provide local sales and support in 160+ countries.

Direct Routing vs Operator Connect vs Calling Plans:
Quick Overview

When evaluating MS Teams as a full telephony solution, businesses often compare Direct Routing, Operator Connect, and Calling Plans. Each option offers different levels of flexibility, coverage, and control.

The table below highlights the key differences to help you choose the approach that best fits your organization’s needs.

For enterprises that need maximum flexibility, cost efficiency, and true global coverage, Direct Routing with a certified SBC for Teams is often the best choice. It lets you bring your own carrier, leverage advanced routing, and scale voice service across 160+ countries with confidence.

Here’s a more detailed comparison: Direct Routing vs Operator Connect.

Achieve Global Connectivity with United World Telecom’s SBC & Teams Integration

For businesses seeking to optimize their Microsoft Teams investment and achieve comprehensive control over their voice communications, United World Telecom provides a robust MS Teams Direct Routing integration.

What You Get with United World Telecom:

• Certified SBC: Enjoy seamless Microsoft Teams Direct Routing with our certified SBC—guaranteeing secure, high-quality voice and full control over call flow, policies, and compatibility.
• Phone Number Coverage in 160+ Countries: Build a local presence worldwide with access to local, toll-free, and mobile numbers in 160+ countries—ideal for supporting global teams and customers while staying connected and compliant.
• Local Caller ID & Advanced Routing: Display a local caller ID to enhance pickup rates and manage your call flow with a routing strategy. Direct calls to the right department or team based on time of day and geographic location. Access 40+ features to manage inbound & outbound calling.
• 24/7 Global Support: Our dedicated team provides expert guidance on integrations and 24/7 global support, ensuring your communication infrastructure is always operational and any issues are swiftly handled, no matter where your teams are located.
• MS Teams Widget Softphone: Use our optional MS Teams Widget Softphone—an intuitive tool that enables click-to-call, call logs, and activity tracking right within Teams, for a hassle-free experience.

Looking to add global voice coverage to your Microsoft Teams setup?

Request a demo or contact our team to explore how United World Telecom can transform your MS Teams voice experience.