Firewalls: Keeping the Big, Bad World Out of Your Firm By MIKE NEWMAN Generally speaking, a firewall is something that protects you. The term was invented by the automobile industry, when designers decided that they needed a solution to prevent passengers from being burned alive when their car engines caught on fire. Their innovation was a steel plate installed in-between the passenger and engine compartments, and they called it a firewall a wall to protect you from fire. In the computer world, a firewall protects your private company computers from all of the evils lurking on the public Internet, usually hackers trying to see what mischief they can cause, or deliberately sabotage or steal information on your private network. There are two kinds of networks: private and public. A private network is a system of interconnected computers, mostly used in businesses and homes. The information and applications that are shared and stored on a private network need to be secured. That is, you don’t want just anyone messing around with your computers or accessing your data. A public network, also known as the Internet, is widely available to anyone. The data that is transmitted across the Internet is largely unrestricted or secured. When you send something across the Internet, such as an e-mail message, it becomes publicly available and can be viewed by anyone with moderate knowledge and a few easily acquired utilities. In the olden days (1990s), network firewalls were not very important. Most companies had a private network of computers, or Local Area Network (LAN), and these computers were not connected to the rest of the world. Nowadays, the need for access to the Internet is vital for most businesses. In this respect, almost every computer in the world is connected to every other computer in the world through this common network: the public Internet. This means that a 14-year-old hacker in Bangkok could use his personal computer to try to break into (or hack into) any other computer in the world. Even worse, hackers can easily create programs (or “worms”) to automatically look for computers all around the world to vandalize or destroy. Gatekeeper Luckily, the invention known as the firewall protects us. A firewall is a specialized computer which acts as a gate between your private company network and the rest of the world. The firewall watches the information going in and out of your network, and allows only what you want to come in and out. For example, almost everyone wants to be able to access Web pages and receive and send e-mail messages. The firewall is configured to let Web pages come into your network, and e-mails pass through. Any other attempt to allow other types of information (like hackers’ programs and other nasty things) to enter onto your network is blocked by the firewall. It’s very easy to see that every computer with a connection to the Internet needs to be protected by a firewall. Even hackers use firewalls to protect themselves! Like most forms of computer gadgetry, there are various features of firewalls, and more features often affect their price. All firewalls offer very basic protection, and some firewalls offer many more configuration options to allow specific types of traffic to cross. For example, some firewalls can prevent certain types of software like AOL Instant Messenger, Napster or Kazaa from working. Some firewalls offer sophisticated monitoring and reporting functions, such as alerting you when someone tries to hack in and steal your data, or sending you a report of which employees go to certain websites. Content filtering Some firewalls offer content-filtering, which can prevent certain employees from viewing inappropriate websites, such as pornography or Monster.com. For the most part, all firewalls were not created equal and you’ll generally get what you pay for. Without going into too many technical details, a $60 Linksys firewall is far less secure and capable as a $1,200 Sonicwall or Checkpoint model. Ultimately, it’s protection that you’re looking for. System engineers can fix or replace nearly anything except for lost, stolen, or corrupted data. This is why network security and solid backup/restore systems are paramount to the continuity of your business. When budgeting for technology, these are the two areas where I recommend not cutting corners and being penny-wise and pound-foolish. Over 50 percent of businesses that lose their data never reopen their doors for business again, and I’ve consoled many a distraught entrepreneur who was suddenly faced with the aftermath of information disasters. Mike Newman is Business Development Manager of Northridge-based Cal Net Technology Group
