Firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. A firewall typically establishes a barrier between a trusted network and an untrusted network, such as the Internet.

"IP Firewall" you may find in the  System Management - System Parameters section.

The Firewall configuration menu was added to limit access to SIP/Web/DB/SSH based on the IP address.

Example of default page:

Rules with IP addresses 0.0.0.0 and Netmask 0.0.0.0 mean ANY IP/ANY Subnet.  On the screenshot you can see that by default, SIP/UDP, Web and SSH access are not restricted (this means that you may have SIP/UDP, Web, SSH access from any IP).  Note, that "access from any IP" doesn't mean that any IP may login to your web interface bypassing the login credentials; it means that the login page would be visible to anyone who knows your IP address. The same applies for all other types of rules.

If a switch operator wants to restrict access (e.g globally - for every entity in the system), he needs to first add the list of trusted IPs using the Rule "Allow", then he can Deny access with a global rule using the IP address 0.0.0.0 (blocking all IPs except the list of IPs added with the Rule "Allow").

Note: For FlySip Softswhitch default netmask: 255.255.255.255

Example for Web type: