1. What is a Firewall
and what does it do?
2. Do I need a Firewall?
3. Where can I download Firewall Software
for my computer?
4. What is Nuking?
What is a Firewall and
what does it do?
A Firewall is a piece of hardware or software/or
a combination of both, designed to protect
networked computers from unauthorized hostile
intrusion. A Firewall sits at the junction
point or gateway between the two networks,
usually a private network and a public network
such as the Internet and examines all traffic/packets
of data routed between the two networks both
incoming and outgoing - to determine whether
it should be allowed to pass or be blocked.
All connections to the Internet are done with
small packets of information. As these packets
are sent from one machine to the other, the
two machines agree on the connection and then
check each other to see if the packets they
sent are being received accurately on the
other end. Every Internet packet must contain
a destination address and port number, so
that the receiving computer knows who sent
the packet also every packet must contain
the IP address and a port number of the originating
machine. In other words, any packet travelling
around the internet contains its complete
source and destination addresses.
Since the Firewall Software inspects each
and every packet of data as it arrives at
your computer - BEFORE it's seen by any other
software running within your computer - the
firewall has total power over your computer's
receipt of anything from the Internet.
A port, opening on your computer to receive
and send data, is only "open" if
the first arriving packet requests the establishment
of a connection and is answered by your computer.
If the arriving packet is ignored, that port
of your computer will effectively disappear
from the Internet. No one and nothing can
connect to it. This is the Firewall theory
and you can accept or reject data from anywhere.
In effect, you can "filter" out
the other computers that you don't want to
see your computer.
Do I need a Firewall?
Nowadays, its advisable to have one especially
if you use the Internet quite a lot, after
all some form of protection/security is better
than having nothing at all. If you are a business,
then Firewall Software can be vitally important
especially if loss or damage of data (caused
by an unauthorized malicious person gaining
access to your computers) would be detrimental
to your company. Using the Internet for short
periods of time is not as open to threat as
much as someone who maintains a 24/7 connection.
For example, if you have a continuous connection
and no Firewall Software, then it's a bit
like going to bed and leaving all your doors
and windows open.
Where can I download Firewall Software for
There are several good free Firewalls
which are available for download. A list of
free Firewall Software is located below for
personal computer security.
4. What is Nuking?
Briefly, there are two types of Denial of Service attacks
(DoS). Otherwise known as a Nuke/Nuking.
1. Ones that exploit bugs and backdoors in
an Operating System which cause a general freezing, Blue
Screen Errors/ crashing of your operating system. These
are generally the worst of all attacks because they can
sometimes force a complete software re-install on your pc.
2. Ones that attempt to flood your connection with data
to force disconnection from an IRC (Internet Relay Chat)
or your ISP (Internet Service Provider)
'Nukes' can take place anywhere on the Net,
whether you're on ICQ, talking to friends,
or just general surfing. The best solution
is the latest operating system patches and
fixes which can help avert this type of attack
especially on some of the older Windows Operating
Systems. Update your Operating System with
the latest security patches and fixes. Get
yourself some Firewall Software, there are
many reliable FREE ones out there.
Lavasoft - Adaware