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Internet Service Provider

ISP & Router Interoperability

Some ISP and their default modem/router configurations can cause interoperability issues with VoIP traffic. This page provides information on ISP/router interoperability issues that you might encounter.

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United Kingdom

O2/Be Unlimited

Issues exist within the default configuration of the BeBox II/III or O2 Wireless Box II/II (actually a rebadged Thomson ST585) where the device binds itself to port 5060. This seems to affect SOME devices attempting to register to a server outside of the local network. e.g. Aastra devices do not register successfully to remote FreeSWITCH servers, yet Siemens S685IP devices do. It is possible to address this issue by configuring FreeSWITCH to allow registrations on ports other than 5060 or by reconfiguring the ST585 router using the information here:

To overcome the limitations, SIP ALG must be disabled by telnetting into the router and running the command:

 connection unbind application=SIP port=5060

See for further info.

The current model supplied as the BeBox router is the Technicolor TG582n.

British Telecom / BT

The BT HomeHub 2.0 includes VoIP capabilities which may interfere with your VoIP devices/FreeSWITCH Registrations. Also see: for potential security issues. Configuration options within BT HomeHubs are limited given the overly simplified user-interface designed for consumers. Suggest using third party routers with QoS capabilities to overcome these limitations.

The BT HomeHub 3 no longer includes VoIP capabilities, but still provides very basic configuration options.