If your Cloud Voice SIP isn't connected to a BT Business Broadband Hub 3, 5 or 6, or if you're using BT-NET to register your SIP Trunks, you'll need to do some configuration changes to your LAN (Local Area Network) or Firewall. The following PDF contains the instructions you'll need to make the changes.
BT Cloud Voice - SIP firewall and LAN guide (PDF, 0.4MB)
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