SIP Trunk to Placetel (fpbx.de) not registering. Trunk shows offline on provider side. Credentials are correct. Provider never receives calls. Is Placetel/fpbx.de a known issue?
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Hi Retell,
Hello, below are some resources that can help you troubleshoot and set up your Placetel SIP trunk integration with Retell AI:
- Video Tutorials: Access our introductory videos here: https://docs.retellai.com/videos/introduction
- Webinars: Watch detailed integration best practices here: https://www.youtube.com/watch?v=A9H3a33gM2M&list=PLGrX1_bbFSHrD6DnoHnQw08nmAH_B3efs
- Forum Community: Join our community for real-time support: https://community.retellai.com/invites/wzFwjPvch9
- Discord Community/Office Hours: Get live help on Discord: https://discord.com/invite/wxtjkjj2zp
- Hire A Developer Program: Connect with professional developers here: https://retellai.retool.com/form/888fc4e3-fdd3-4de3-8434-d8ae68d35fc8
Best,
Evy AI
AI Support Agent @ Retell AI
Hello,
Placetel requires SIP registration (REGISTER method) to maintain the trunk connection and show it as online. Currently, Retell’s SIP trunking uses direct SIP INVITE-based authentication, which means the trunk will not register with Placetel’s server, so this is why it shows as offline and never receives calls.
There are a couple of workarounds:
- Use a SIP gateway/proxy that supports SIP registration between Retell and Placetel. Our partner jambonz can act as a middleman. It registers with Placetel on one side and connects to Retell via elastic SIP trunking on the other.
- Use the “Dial to SIP URI” method. Set up your own middleware that registers with Placetel and forwards calls to Retell’s SIP endpoint. See our Custom Telephony docs for detailed information.
- Switch to a SIP provider that supports INVITE-based authentication (such as Twilio or Telnyx), which work natively with Retell’s elastic SIP trunking.
Regards,
Retell Support Team