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Source : http://www.thedailystar.com/lifestyle/2 ... h1217.htmlTech GP: Firewall essential if you use the Internet
Since I began writing the column, a couple people have suggested that I write one about firewalls and their importance.
I was hoping to include firewalls in a review of local Internet service providers, but I havent gotten enough feedback from readers to do an ISP review yet, and firewalls are an important concept, so we wont wait any longer.
So, just what is it were talking about?
A firewall is something either hardware or software that is wedged between your computer or network and the rest of the world (the Internet), and acts like a filter.
As you interact with the Internet, you actually do it by sending and receiving packets of information. A firewall lets some packets of information through, and blocks others from going through, using a set of rules to decide what passes and what doesnt.
A long time ago, when the Internet was young and innocent, a firewall wasnt such a big deal. This was before terms such as "worms," "denial of service attacks," "malware," "identity theft" and the like became mainstream news items.
Times have changed, though. Black hats all over the world have tread the Internet, and they want to sneak into your computer through the back door without you knowing it.
Recently, someone did a study and found that a computer without a firewall between it and the Internet lasted less than 15 minutes before it was "owned" by someone other than the real owner.
That is amazing and frightening.
Thats why were having this conversation.
If you dont already have one, get one.
Now, on to the particulars. You may already have a firewall in place without knowing it.
If you are using the latest version of Windows or Macintosh software, you already have one included with your operating system. You just have to make sure its turned on.
If you have a network on which several computers connect to the Internet via a router, you probably already have one built into the router. This type of firewall is usually enabled by default, so unless you have disabled it yourself, youre probably OK.
The two preceding paragraphs illustrate two different types of firewalls, one a software program, and the other a hardware device. Each type has its particular advantages. They both work, and there is nothing that says that you cant use both. In fact, many people do.
A hardware device, such as a router, is easy to set up.
In fact, if you have connected the router between your computer and cable/DSL modem, and everything works, youre pretty much done. Many households and small businesses go this route in order to let more than one computer at a time use a single Internet connection, but you can still get and use a router even if you only have one computer.
A software program running on your computer generally is more interactive, and is easier to fine-tune. They are also more prone to creating networking problems between computers on your own network, if you make a mistake configuring them.
If you use a dial-up Internet connection, you should get a software firewall. Using a router is usually not an option for a dial-up connection.
If you have an older operating system, you probably dont have a firewall program on your computer by default. In this case you have to take the initiative to get one, or go down the hardware road.
There are a number of software firewalls available. I am not going to recommend one as being better than another. Some companies make different versions, with a basic program available for free use, and a more sophisticated version that you can "upgrade" to (pay for). ZoneAlarm, Kerio and Sygate are examples.
Sometimes, your Internet provider will give you a firewall program to use for free, or for an additional monthly charge, as long as youre a customer of theirs.
The important thing is not so much which firewall you use, as long as you use one.