|
What is a Firewall?
A firewall
is a piece of hardware and/or software that "sits"
between your computer and the Internet in order to
filter the traffic going back and forth. It acts,
as a security checkpoint so that unauthorized data
transfer doesn't occur. If this kind of transfer does
take place, it could allow a black-hat hacker or a
script kiddy to gain remote access to your computer
or let a Trojan horse (see Anti-Trojan) exploit your
computer.
How does a firewall work?
When a web page is requested or you
are chatting on the Internet, the information is sent
back and forth in little envelopes called packets.
It works much like our postal system using an envelope
with the destination and return information on the
outside and the actual letter or data on the inside.
This is how information is passed back and forth over
the Internet.
The firewall then checks the envelopes
and the data to make sure that it is authorized to
go to the person it is addressed to and that the person
or application sending the data is authorized to use
the Internet. For instance, Internet explorer or AOL
would be authorized to send data, but a Trojan horse
or some other unknown application would be prohibited
from doing so until it could be verified why it is
using the Internet.
Why do I need a firewall?
A firewall provides that extra level
of protection that you can’t get from an anti-virus
program. In fact, the general public regards firewalls
the way anti-virus software was viewed during the
early 1990’s. At that time, no one would purposely
go out and buy the software unless a virus had attacked
their computer. The same mistake should not be made
with firewalls, because the consequences could be
much greater if your computer is exploited.
Some people say, “I don't care
if I get hacked, I don't have anything on here anyway.”
Well, a hacker may not be interested in your computer
directly, but use it indirectly for their criminal
purposes. If your computer is hacked, it can be used
to gain others and cover the tracks of the hacker,
leaving you "holding the bag.”
There really isn't any excuse not
have a firewall. There are even some "lite"
versions, which are distributed for free and provide
adequate protection.
Lite Free versions:
Zone Alarm
Sygate Personal Firewall
|
