Security: Firewalls

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If you spend a lot of time on the internet and you are not behind ...
then you are living on borrowed time. Putting some ...
you and the internet is probably the third most import If you spend a lot of time on the internet and you are not behind afirewall, then you are living on borrowed time. Putting some protectionbetween you and the internet is probably the third most important thing thatyou can do (after getting virus checking software and performing regularbackups).The diagram to the left shows an unprotected system using a DSL modem.
Asyou can see, someone on the internet can attach the computer system easilyas the DSL modem provides no protection (some DSL modems have built-infirewalls). An attacker can get through any type of modem - DSL, cable, 56K,28.8 or whatever.
If the device gets you on the internet, you arevulnerable.For those with a DSL, cable modem or other "always-on" connection, you MUSTget a firewall. This is critical, as your machine is always live and it mostlikely has a fixed IP address.
This makes it easier for your system to be"found" and attacked.What a personal firewall does is isolate your computer from the rest of theinternet. It does this by inspecting each packet of data to determine if itit should be allowed to get to (and in some cases from your machine.) Thebest protection completely hides your computer - this is called stealthmode.You have the option of installing a software firewall or a hardwarefirewall.Software Firewall - A software firewall runs on your computer system in thebackground.
It intercepts each network request and determines if the requestis valid or not. Software firewalls offer the following advantages:- They are generally very inexpensive- They are very easy to configureThey have the following disadvantages:- Since they run on your computer they require resources (CPU, memory anddisk space) from your system.- They can introduce incompatibilities into your operating system.- You must install exactly the correct version for your operating system.- You must purchase one copy for each system on your home network.Hardware Firewall - A hardware firewall is generally a small box which sitsbetween your computer and your modem.
In general, hardware firewalls havethe following advantages:- They tend to provide more complete protection than software firewalls- A hardware firewall can protect more than one system at a time- They do not effect system performance since they do not run on yoursystem.- They are independent of your operating system and applications.They have the following disadvantages:- They tend to be expensive, although if you have a number of machines toprotect it can cost less to purchase one hardware firewall than a number ofcopies of a software product.- Since they do not run on your computer, they can be challenging toconfigure.Firewall mixture - In my mind, the best protection is a combination of bothhardware and software firewalls. This is the ideal, since both havedifferent advantages and disadvantages.
Personally, I use a SonicWallhardware firewall combined with ZoneAlarm Pro, which is installed on myWindows 2000 Professional system. The SonicWall protects my home networksince it sits between the hub and the DSL modem, and ZoneAlarm Pro offerssome additional protection for each system.Testing Your Firewall - To test your firewall, surf to http://www.grc.comand request a probe.
You will be given a very good report of exactly whatissues were found and what to do about them. Once the probe is finishedseveral excellent personal firewall products are recommended.
My personalfavorite is ZoneAlarm Pro, primarily because it's protection is excellentand it is trivial to use.Some Firewalls - A selection of personal firewalls is listed below.- ZoneAlarm Pro - By far the best software firewall available. ZoneAlarmoffers protection from both incoming connections and outgoing connections.It is also extremely easy to configure, has low system impact and is veryinexpensive (a free version is also available).- Norton Internet Security 2001 (which was the AtGuard product from WRQuntil a few months ago).
Norton is a reasonable firewall, although it doeshave some vulnerabilities. It offers weak protection from outgoingconnections and is somewhat difficult to configure if you want it to operatedifferently from the default.- BlackIce - A good choice in firewalls.
Much easier than Norton toconfigure, but with the same vulnerabilities.What I've done on my system is:- Used a SonicWall hardware firewall to protect my entire home network.- Installed ZoneAlarm Pro on ach system to provide additional safety- And installed Norton Internet Security for it's privacy protection.Due to the rapidly changing nature of the internet, it's very important tobe continually monitoring security issues. You may purchase the perfectpersonal firewall today, only to find out in six months that it's beenhacked to pieces.
So be sure to be looking around, and be ready to get anewer and better product quickly. This is not one of those issues where youcan scrimp and save.
Your system is at risk. Article Tags: Software Firewall, Software Firewalls, Operating System, Hardware Firewall Source: Free Articles from ArticlesFactory.com .