To allow Neural's VoIP traffic to flow through your firewall, please add an accept inbound & outbound rule for the following addresses:
188.8.131.52/28 (184.108.40.206 - 220.127.116.11)
The ports required are:
- 5060 UDP/TPC for signalling
- 10000 - 20000 UDP for RTP audio
It is important that you do not forward these ports, but rather 'white list' or allow them through any ACL's on your router/firewall.
If you are using a custom built hosted solution or a call centre PBX, you will also need to add the IP for that server.