Firewall Platforms
Firewalls may be implemented using hardware or software platforms. Implementing hardware will provide
performance with minimal system overhead. Although hardware-based firewall platforms are faster, they are not
as flexible or scalable as software-based firewalls. Software-based firewalls are generally slower with significant
systems overhead. However, they are flexible with additional services; for example, they may include content and
virus checking before traffic is passed to users.
It is generally better to use appliances, rather than normal servers, for the firewall. Appliances are normally installed
with hardened operating systems. When server-based firewalls are used, operating systems in servers are often
vulnerable to attacks. When attacks on operating systems succeed, the firewall can be compromised. In general,
appliance-type firewalls are significantly faster to set up and recover.