> ## 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.

# Grandstream UCM

> Connect Grandstream UCM series PBX to SmartAlex via SIP trunk.

<Info>
  **Audience**: Grandstream UCM admin. **Time**: 10 to 15 minutes. **Models**: UCM6200, UCM6300, UCM6500 series.
</Info>

## Prerequisites

* UCM admin access
* Firmware 1.0.20 or later (older firmware has SIP interop issues)
* Outbound UDP 5060 allowed
* SIP ALG disabled upstream

## Step 1: create trunk in SmartAlex

SIP Trunk wizard, pick **Other** (Grandstream defaults match generic). Save credentials.

## Step 2: add the trunk in UCM

<Steps>
  <Step title="Open SIP trunks">
    UCM web UI, then Extensions/Trunks, then VoIP Trunks, then Create New SIP Trunk.
  </Step>

  <Step title="Type and provider">
    * **Type**: Register SIP Trunk
    * **Provider Name**: `SmartAlex`
    * **Hostname**: `sip.voice.getsmartalex.com`
    * **Transport**: UDP
    * **Keep Original CID**: No
  </Step>

  <Step title="Detailed settings">
    * **Username**: (from SmartAlex)
    * **Password**: (from SmartAlex)
    * **AuthID**: same as username
    * **From Domain**: `sip.voice.getsmartalex.com`
    * **Outbound Proxy**: `sip.voice.getsmartalex.com`
    * **DID Mode**: Request Line
  </Step>

  <Step title="Codec">
    Enable PCMU and PCMA. Priority: PCMU first.
  </Step>

  <Step title="Save and Apply">
    Save, then Apply Changes. Registration should show green within 30 seconds.
  </Step>
</Steps>

## Step 3: inbound route

Call Features, then Inbound Routes. Add a route: DID to the SmartAlex trunk.

## Step 4: extensions and agent

Add extensions in SmartAlex. Link agent in Agent Studio.

## Step 5: test

Call DID. Transfer.

## Grandstream-specific notes

* **SIP ALG on Grandstream routers**: if you're running a Grandstream router in front of the UCM, double-check SIP ALG is disabled there too.
* **Fax / T.38**: not relevant for AI voice; leave at defaults.
* **UCM hosted vs on-premise**: configuration identical.
* **Call recording**: UCM records trunk-level calls by default. If you don't need the SmartAlex leg recorded separately, disable it on the trunk.

## Next steps

<CardGroup cols={2}>
  <Card title="Generic SIP" href="/telephony/generic-sip">
    Common fallback reference.
  </Card>

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