This guide works great, with the one amendment; PJSIP Registration should be set to “none”.
https://frag.co.uk/2017/08/14/cisco-spa-3102-freepbx-uk-caller-id/
Critical config info is as follows:
SPA-3102 Configuration
Admin login > Advanced > Voice > PSTN Line:
- Line Enable: Yes
- SIP Transport: UDP
- SIP Port: 5060
- SIP Remote-Party-ID: Yes
- Auth Invite: Yes
- Proxy: [set to FreePBX IP]
- Register: No
- User ID: pstn_fxo
- Auth ID: pstn_fxo
- Use Auth ID: Yes
- Password: password
- Line 1 VoIP Caller DP: None
- PSTN Caller Default DP: 1
- Dial Plan 1: (S0<:pstn_fxo@192.168.0.181>)
Including brackets – and where 192.168.0.181 is your FreePBX IP
FreePBX Configuration
Create a new PJSIP Trunk
- Trunk Name: <My DID>
- Outbound Caller ID: <My DID>
- Maximum Channels: 1
- Username: <My DID>
- Password: password
- Authentication: Outbound
- Registration: Send
- SIP Server: [set to IP address of SPA-3102]
- SIP Server Port: 5060
- Context: from-pstn
- Contact User: <My DID> (thanks to Aly)
Inbound Route
- Set up a default route with Destination as a Ring Group
Outbound Route
- Route Name: POTS Outgoing
- Route CID: <My DID>
- Trunk Sequence for Matched Routes: <My DID>
More notes:
https://basichelp.sipgate.co.uk/hc/en-gb/articles/206289069-UK-Regional-Settings-Cisco-Linksys-Sipura-Adaptors-