> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getsmartalex.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Microsoft Teams Phone

> Connect Microsoft Teams Phone to SmartAlex via Direct Routing and a Session Border Controller.

<Info>
  **Audience**: Microsoft Teams Phone administrator and SBC owner. **Time**: 2 to 4 hours for a new SBC deployment; 30 minutes if SBC already configured. **Requires**: Session Border Controller.
</Info>

## How Teams Phone integrates

Microsoft Teams Phone doesn't speak raw SIP trunking to external providers. It uses **Direct Routing** through a **Session Border Controller (SBC)**.

```mermaid theme={null}
flowchart LR
  A[Microsoft Teams] -->|Direct Routing SIP over TLS| B[SBC]
  B -->|Standard SIP| C[SmartAlex]
```

Your SBC sits between Teams and SmartAlex, translating Teams-specific SIP to standard SIP.

## Certified SBCs

Microsoft certifies specific SBC products for Direct Routing:

* AudioCodes Mediant series
* Ribbon Communications (formerly Sonus) SBC
* Oracle Acme Packet SBC
* Cisco CUBE

Any of these work with SmartAlex. The SBC configuration is what differs.

## Step 1: create trunk in SmartAlex

SIP Trunk wizard, pick **Microsoft Teams**. Defaults set TLS transport and SRTP for compatibility. Save and copy credentials.

## Step 2: configure your SBC

Two legs to configure on the SBC:

### Leg A: Teams side

* Direction: toward Microsoft 365
* Transport: TLS on port 5061
* Certificate: publicly-trusted certificate matching your SBC's FQDN (e.g., `sbc.yourcompany.com`)
* Peer: Microsoft 365 SIP endpoints (use the SBC's Teams interop template)
* Media: SRTP mandatory

### Leg B: SmartAlex side

* Direction: toward SmartAlex
* Transport: UDP on port 5060 (or TLS on 5061 if required; see notes)
* Peer: `sip.voice.getsmartalex.com`
* Authentication: SIP digest (username and password from SmartAlex)
* Media: RTP or SRTP per your policy

## Step 3: Teams admin centre

<Steps>
  <Step title="Add the SBC as a PSTN gateway">
    Teams Admin Centre, then Voice, then Direct Routing, then Add. Enter your SBC FQDN and port 5061.
  </Step>

  <Step title="Create a voice route">
    Voice, then Voice Routes, then Add. Pattern to match numbers you want routed via SmartAlex. Target: your SBC.
  </Step>

  <Step title="Create a voice routing policy">
    Assign the voice route to a policy.
  </Step>

  <Step title="Assign policy to users">
    Users who call numbers routed via SmartAlex need the policy assigned.
  </Step>
</Steps>

## Step 4: extensions and agent

Configure extensions in SmartAlex. Link agent in Agent Studio.

## Step 5: test

Dial from a Teams user to a DID routed through SmartAlex. The call should arrive at the AI agent via your SBC.

## Teams-specific notes

* **SBC is mandatory**: there's no direct Teams-to-SIP-provider path without one. Teams Operator Connect and Calling Plans are different products (Microsoft's own carrier services) and don't apply here.
* **Certificate requirements**: Teams Direct Routing requires a public certificate from a trusted CA on the SBC's Teams-facing side.
* **Bypass vs non-bypass mode**: Media Bypass (where RTP flows directly from Teams client to SBC without traversing Microsoft 365 media servers) reduces latency. Configure on the PSTN gateway in Teams Admin Centre.
* **Capacity**: each SBC has its own call licences and capacity limits.
* **Teams Phone vs Teams calling**: this guide is for Teams Phone (PSTN-enabled). Teams calling without Phone doesn't support Direct Routing.
* **Enterprise only**: we treat Teams integrations as Enterprise tier due to the SBC complexity. Contact your account manager to confirm scope.

## Common pitfalls

<AccordionGroup>
  <Accordion title="Teams rejects incoming calls from the SBC">
    The SBC FQDN must exactly match the certificate. Teams also verifies the certificate chain. Inspect the Teams event log under Monitor, then Call Analytics.
  </Accordion>

  <Accordion title="One-way audio Teams-to-SmartAlex">
    Almost always SIP ALG or misconfigured NAT on the SBC. Verify SBC has a routable external media IP configured.
  </Accordion>

  <Accordion title="SBC works for Teams but not SmartAlex">
    Leg B (SmartAlex side) of the SBC config is usually the issue. Common: authentication credentials mis-typed, or Leg B is TLS-only and SmartAlex ingress expects UDP without cert validation.
  </Accordion>
</AccordionGroup>

## Next steps

<CardGroup cols={2}>
  <Card title="Network Requirements" href="/telephony/network-requirements">
    Firewall and TLS details.
  </Card>

  <Card title="Troubleshooting" href="/telephony/troubleshooting">
    Error reference.
  </Card>
</CardGroup>