The NX32 SBC allows you to connect remote sites and users as well as bridge 3CX instances. Ideal for businesses who have remote workers and offices and need the on-site installations to be able to communicate with each other. Easily managed from the Call4tel cloud portal, updates and settings can be configured remotely.

For remote sites with a number of remote phones, deploy the 3CX SBC and all phones will communicate with the 3CX PBX over a single port. This is also the preferred option in case 3CX is running in the cloud. 

The 3CX apps for Windows, Mac, iOS and Android have a built-in tunnel that is used automatically when the 3CX app detects its not on the LAN.

When creating a Bridge to another 3CX installationyou can use the 3CX SBC rather than a direct connection. 

NX32 SBC - how it works

The image above demonstrates how the 3CX SBC works. In this example, 3CX is on IP Address, and listens on TCP port 5090 (by default) for incoming Tunnel traffic. A single port forwarding rule on the NAT/Firewall Device is required, to inform 3CX that all incoming TCP and UDP traffic received on port 5090 should be delivered to LAN IP Address 

The remote setup is shown on the left-hand side of the cloud. In this example, the machine with IP address of has the 3CX app installed. We need to inform the IP Phone of the public IP address of the PBX Server (which in this case is, and also the private IP address of the PBX Server (which in this case is Since the 3CX app will by default use the standard port numbers used by 3CX, typically no further configuration is necessary. 

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