Connection setup of an audio/video chat or SIP softphone call fails. A media connection cannot be established.
Possible reason
The message indicates a problem with the internet/network connection or restrictions due to security settings for the connection between UCServer/UCConnect/ProCall Clients, for example, if they are not on the same network.
Example Scenarios
This applies for example to:
Mobile clients where softphone calls are to be made via the ProCall Mobile App using mobile data (LTE or similar)
ProCall Enterprise clients in the home office that access the UCServer via NAT port forwarding
Other scenarios in which the ProCall clients are not directly connected to the UCServer
VideoChats via SIP-Federation (with users at other locations/in other company networks)
Use of LiveChat for audio/video communication with website visitors
Changes to network or security settings require special expertise and access rights.
Firewall configuration
In order for SIP softphone and audio/video chat to work in the above-mentioned internet scenarios, the following port permissions must be set on the firewall:
Direction: Outbound traffic
Source-addresses: <All internal addresses> (Concerns in particular: UCServer and ProCall Clients, possibly with DHCP addresses)
Source Ports: <All>
Target addresses: <Public address of the used TURN server> (when using UCConnect: ucturn.ucconnect.de)
Destination ports: 3478 and 443
Transport types: UDP and TCP
Test in UCServer
The UCServer Admin can be used to test whether the UCServer or the media proxy can establish a connection to the TURN server. The STUN and TURN diagnosis can be found under Services → STUN / TURN.