We have an IP office 9.0 system with SIP trunk on LAN2 with a public IP on the LAN2. The system gets hacked regularly. A complex password is no trouble for the hacker.

We put the IPoffice lan 2 behind a firewall with SIP trunk connectivity results in one way speech.

I used Pfsense and had no luck. 2 days of banging my head against wall is no fun.

So I am hopeful someone can advise me on a product/firewall that will work easily.