This article explains how to disable SIP ALG on the BT Business Hub modem router. This router is generally supplied by BT to business customer.
Although this guide was written with the BT Business Hub 5 router in mind, the guide below should be applicable to similar BT Business Hub routers.
Step-by-Step Guide
The BT Business Hub has been known to expose your handsets to the Internet. You may experience random 'phantom' phone calls, possibly at inconvenient times. This will be due to hackers scanning your network.
Jibba Jabba can not be held responsible for costs incurred where compromised equipment has been used fraudulently or otherwise misused.
We suggest purchasing a router more suitable for business use with a better security track record, such as a DrayTek router.