You can find a wide variety of firewall products on the market today, comprising three basic physical firewalls: software based, appliance based, and integrated | Firewall Products You can find a wide variety of firewall products on the market today comprising three basic physical firewalls software based appliance based and integrated. Software-based firewalls as discussed previously typically run on top of a commercial operating system such as Sun Solaris or Microsoft Windows. Appliance-based firewalls are purposefully designed devices in which the filter and inspection software is tightly integrated into a custom-built or hardened operating system. These firewalls include the Cisco PIX products as well as Juniper s NetScreen firewalls and the Symantec Enterprise Firewall. Finally there is the integrated firewall which is somewhat of a synthesis of other products with the traditional firewall. Whereas in the past multiple security devices such as firewalls VPNs and intrusion detection systems were all based on different devices recent movement in the industry tends toward integrating all three devices into one platform. This synthesis has the benefit of reducing the number of hardware devices that require administration and thus lowering the administrative overhead necessary to deploy and manage these devices. Examples of integrated firewalls include the Cisco ASA and the TippingPoint X505 devices. The following sections discuss each of these firewall products in further detail. Software Firewalls Software firewalls are installed on top of an all-purpose generic operating system. Software firewalls include the Sun SunScreen firewall IPF the Microsoft ISA Server Check Point NG Gauntlet Linux s IPTables and FreeBSD and OpenBSD s pf packet filter. Typically the vendor s firewall software suite includes patches as well as configuration changes that must be applied to harden the underlying operating system from attack or to include a kernel module or driver for the firewall to operate properly. The primary advantage of such firewalls is that you can task them to be multipurpose in nature. For example a firewall can also be a .
