I tried install the Linux Firewall to protect our VOIP system but I found
that the voice delay increased after it.
Is it impossible to install any firewall to protect VOIP system? If no,
What kind of firewall I can use. Or Any suggestion can let me setup that
only allow specified IP address to access our internal VOIP network. Please
I think firewalls shoudn’t be a problem for VoIP. There could be several other reasons for the delay which you saw when you introduced a firewall. I saw watchguard as well as pix firewall working very well and allowing voice traffic. You should allow port 1720 for voip communication. Please try this option…..