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Question: What is a firewall?

Answer: A firewall looks at the information passing through the gateway and determines whether to allow the information to continue on to its destination.

A firewall is used to control traffic in and out of a secure network. It basically filters all of the packets of information and determines if it meets acceptable criteria. A firewall can give the system administrator the ability to limit access to internal resources and also define acceptable types of traffic for connections to the outside.

One of the simpler ways that a firewall works is to only accept information from certain IP addresses or domain names. If you request information and you don't come from a certain predefined allowed connection - you don't have access. For more flexible access, it might be necessary to set up a login and password to allow authorized users access while at different sites.

Firewalls give the system administrator the ability to limit access to their network. But it can also limit traffic to other specific sites (or enforce security policies.)

It has its pros and cons.

Cons

• Many users feel that their access to the outside world is being restricted and their privacy invaded.
• It can be expensive for the equipment and for proper administration.

• Keeps people from the internet out of your internal network.
• Allows the network administrator access to who has access to which information they want publicly broadcast.
• Prevents and reports policy violations and unauthorized attempts to gain access.
• Logs violations and usage

Answer: No, not directly. You should still have a virus protection program if you are behind a firewall.

Answer: Basically, if your ISP want to restrict where you go, they can. If they don't restrict where you go they can still tell exactly where you go. All of the information that you receive on your computer has to pass through the firewall and if they want to log any of that information it is just the push of a button.

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