|
Setting up a Firewall |
A firewall is a way of blocking unwanted network
activities. Such activities can include a program trying to use the
internet or other internet users trying to connect to your computer.
There are a few different ways Windows users can implement a
firewall. If Windows XP with Service Pack 2 is being used, Windows
has a built-in firewall that is enabled by default. There are also
third-party firewall programs that can be installed. A router, and
some broadband modems, should have firewall capabilities. While they
all do basically the same thing, each has different benefits and
drawbacks for each individual user.
The Windows firewall can be configured to block any undesired
incoming and outgoing traffic. It is simple to configure, and comes
free with Windows XP. However, it does not have many other features,
or any useful advanced features. To enable and change any Windows
Firewall settings, open the control panel by clicking the “Control
Panel” item in the Start menu. If “Windows Firewall” is visible,
open it. If not, open the “Network and Internet Connections” section
and then open “Windows Firewall.”
In the General settings tab the firewall and exceptions can be
enabled or disabled. In the Advanced tab, you can choose which
connections you want the firewall enabled for. If it is disabled for
any connection, all network traffic will be allowed on that
connection. Exceptions allow any programs you choose to be able to
use the network how you want. For example, you can allow a program
unrestricted access to use the network, or you can allow a specific
port number to be usable by any program. If you have Windows
Firewall enabled and a program tries to access a restricted port
(one that you have not explicitly allowed), you might be prompted to
either allow the program access or to keep blocking that program.
This can allow easy configuration, sometimes. If you run a
network-enabled game and are prompted by Windows Firewall, telling
it to allow that connection will add an exception for it to have
unrestricted network access. Windows Firewall has the benefits of
being free with the operating system, and many newer programs can
automatically add exceptions when they are installed. However, there
is a chance that programs can make undesired changes to the
exceptions list and still gain access to the network.
Third-party firewall programs allow more fine-tuning of the allowed
and blocked network traffic, as well as more advanced features and
friendlier logging capabilities. Common third-party firewall
programs include Zone Alarm and Norton Personal Firewall. These are
installed as any other program would be, and are best used as a
replacement for Windows Firewall instead of in addition to it. These
programs are usually well-documented and easy to get started with,
but are usually not free for full versions.
Routers often block incoming traffic by default. This is because
multiple computers can connect to a single router, and the router
does not (by default) know which device to send the traffic to. Just
as software firewalls, exceptions can be set to forward a specific
port number to a specific computer. This is known as Port
Forwarding. In this form, routers can be thought of as half a
firewall. It will block any unwanted incoming network connections,
but programs can usually still make connections to the internet
without restriction. Some routers include full firewall abilities,
but they must be configured before they become active. This is
obviously not an option to someone without a router or broadband
modem that has firewall support, but this can be the safest method
since it cannot be tampered with by rogue programs running on the
computer. |
|
|
|
