We would like to switch from our ISDN to SIP trunk. The MitelBorderGateway should implement the SIP trunk. But we have the problem that the SIP trunk cannot be registered. We are at the provider HFO Telecom AG. We have made the following settings. Maybe someone will spot the mistake right away.
We use so-called audio codes which are provided by the provider. These provide the A-DSL line and the entire SIP routing in the operator's networks is routed to the audio codes via our firewall. Then it goes into the HFO network. A corresponding tracer from the PBX confirms this.
Thank you for Answers!