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Welcome to our Newsletter


What is a Firewall? Do I need one? Am I really protected? I have been asked these questions many times. Below is an article explaining Firewalls and what they are and how they work. Every situation is different, let us help you choose the correct Firewall for your needs.      Click Here

I'm not sure if everyone knows yet. We moved our office. We needed more space so we moved into a larger office suite in the same building. Our new office address is: 420 North Sacramento Street, Suite #6, Lodi, California 95240. The phone number remains the same 209-368-5252.

Free Lunch!  Everyone enjoys a free lunch. You may have heard the phrase "There's no such thing as a Free Lunch." Well, here it is. If you refer a new customer to us and that customer results in a minimum of one hour of computer service, YOU will receive a $10 gift card to spend at a local restaurant. Details

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Gregory Walther
Press-F1 Computer Service

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Feature Article



Firewalls Explained

Hardly a day goes by without my inbox stuffed with news of a new virus or worm and even worse a vulnerability discovered in some program I'm using. Of course you can't ignore issues like these but there are steps you should be taking to sleep well at night. Anti-virus software is a must but that is only half the battle. You need to be able to keep unwanted visitors out and sensitive data in and that's the job of a firewall.

What is a firewall?

In simple terms a firewall is a hardware or software device that acts like a fence around your system or network. It would be great just to put up a big fence and never let anyone in. By doing that, you would lose all communication with the outside world.

So what is needed is a walled garden with access to and from a limited amount of applications and data that you trust. That is exactly the job of a firewall. Of course they range from free software only firewalls to full corporate wide hardware systems.

How does it work?

There are a number of technologies employed by firewalls to protect your data and network, the first is a simple set of rules. This permission based scheme plugs the holes that Windows operating systems are sadly renowned for. Your Windows operating system has many holes in it, some must remain for applications like email and web browsing to get to the Internet, but Windows ships with many other holes or "ports" open.

For example, many home machines will never network with another machine in their entire life, but as standard they ship with the NetBIOS ports open. There are a number of viruses and hacking tools that exploits this simple fact and there is an equally frightening number of home PC's right now with this port wide open.

A simple rule set starts from the position of all ports (or doors) closed and then as you start each application you have to create a rule to let it get to the Internet or network. Most firewalls will come configured to allow Internet and pop3 email access from start-up but you'll find that instant messaging like MSN messenger and Yahoo IM will need permission to work.

What types are there?

There are 2 physical types of firewalls, software and hardware. Software firewalls are commonly used in the home environment. Big names like Norton and MacAfee both make and sell Internet personal firewalls, these do a pretty good job of providing a basic rules based protection system by running an application on your PC.

Hardware firewalls are more common in business environments where dedicated units have the outside world plugged in on one side and the trusted network on the other. These are often supplied as a pair so that failure of a unit does not make the network vulnerable.

Both hardware and software firewalls use a number of different techniques to keep your PC and network safe. All data incoming and outgoing is inspected to see that it is coming from and going to trusted ports on the system and possibly even trusted IP addresses.

The next level up is a proxy server, this stands between the outside Internet and the trusted network. It intercepts all packets of data and checks if they meet the packet filter rules before forwarding data to the machine inside the trusted network. This adds a level of security by never letting the Internet machine talk directly with the trusted machine. A system of Network Address Translation (NAT) hides your internal IP address from the Internet meaning all data has to go through the firewall for inspection. A proxy server is very good against brute force attacks, the equivalent of someone trying to shoulder charge your door down, its like putting an extra set of doors between your machine and the attack.

The best level of firewall technology is normally found only in high end firewalls but is slowly creeping into the top end home devices. This not only applies rules to incoming data it checks various security protocols and can determine if data is really from whom it claims to be. This is in effect a smart firewall which is looking for known characteristics of certain attacks and spoofing attempts.

Most firewalls use at least 2 of these techniques and the best firewalls are a combination of all three. Plus most corporate firewalls use a combination of hardware and software to protect their networks.

Do I really need a Firewall?

Well it depends, most dial up users would not benefit from the extra security and would be hindered by the downsides covered in the next section, as dial up users get assigned a new IP address every time they connect it would be very difficult for hackers to find the machine before you end your surfing session.

With broadband you should get some kind of firewall protection, For example, a computer connected to a broadband connection will keep the same IP address until rebooted. That's the only time your ISP gives a new IP address.

So a broadband user connected for enough time would make it worth while searching for open ports and trying to get in, or for a Trojan program on a machine inside a network to get out and do some damage.

There must be a downside to Firewalls?

Of course there is some downside, almost all firewalls have some performance issues. Anything above the simplest packet inspection system will slow down traffic in and out of your network. Not by much but it will have an effect. On a broadband connection this is hardly noticeable but on dial up its just another drain on a small 56k connection. Also some of the software based firewalls eat system resources on the host PC.

What should I get and where do I get it?

If you decide that you should look at protecting your single PC and do not plan to build a network, then a software system would be sufficient. If you have a network then the best bet for the home user is a router with a firewall, be it wireless or cabled manufacturers offer competitively priced devices with a good solid firewall.

We would be glad to discuss your needs and suggest appropriate solutions. Call Today.

If you have a particular question or subject in mind, send us a note and we will share some information on the subject. Reader input is the key to a useful newsletter.

For more information, tips and resources visit I hope you find this information interesting and useful. If you have any questions or need further information.  Call Today.



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