Firewall Install and Configuration

Why use a Firewall?

A firewall restricts the data flow in and out of a computer network. To use a simple analogy, a firewall is like a doorman at the entrance to a private members club. He checks entrant's names against a members or guest list and if their names are on this list, he lets them in. If their names are not on the list, they get refused. This is the same principle in which a firewall works. It is an extra layer of protection determining which data gets in and out of your network.

There are other reasons to use a firewall:

A firewall creates an audit of activity on your network. If you are suspicious that somebody was trying to access your network without permission, you can look at the firewall logs for evidence of intrusion attempts.

Firewalls can also provide protection from routing-based attacks, such as source routing and attempts to redirect routing paths to compromised sites via Internet control message protocol redirects.

A firewall can be less expensive for an organisation, in that all or most modified software and additional software could be located on firewall systems as opposed to being distributed on many local hosts.

Firewalls can be used to block DNS information about site systems; thus the names and IP addresses of site systems would not be available to Internet hosts. By blocking this information, you make any hacking attempts more difficult.