What is a Firewall?

A Firewall is commonly used to protect a network from the outside world against any unauthorized to the network. Interestingly, term ‘Firewall’ actually got its name from a construction industry where a protection mechanism was deployed in building against fire hazards.

Firewall protects the network of the organization from unauthorized users in such a way that only authorized users in the outside world may access the software and hardware resources of the organization.

Firewalls are basically a software that is placed on the gateway to protect from unauthorized users. It is usually done by placing a dedicated computers at the gateway which verify the authenticity of various users. So, firewall is also known as secure internet gateway.

Firewall is a system which has a collection of devices, computers softwares routers hosts or collection of hosts. It works by screening the message packets that are passed through the gateway for the purpose of accessing the internal network.

There are lots of paid and free firewall available. Most internet security suit comes with a firewall. Some good free firewall are Comodo Firewall, Zone Alarm Firewall. However there are also a few good paid firewall softwares available such as Kaspersky Firewall, Norton Firewall etc.

Originally posted 2008-06-27 00:01:50.