Computer Security Buying Guide

Know thy enemy

Before you decide what steps to take to protect your data and information, it's important to be clear on the nature of the threat. When it comes to computers, there are two basic types of intruders: those committing computer vandalism and information thieves.

Computer vandals range from the fairly innocuous intruder that wants to look around simply because "the door was open" to someone who's looking to make their presence known, often just so they can say that they did it. Either way, these vandals often leave some kind of damage in their wake. However, vandals are easy to deter with a modest amount of security, and their intentions, while not exactly honorable, are typically not malicious. Of course, a vandal might make the transition to thief if they come across something valuable, so don't take chances.

Information thieves, on the other hand, are any type of intruder that seeks to gather personal information about you and use it for their own gain. This can include identify thieves who use your financial information, be it credit card numbers or your credit rating, for unauthorized purchases; people who collect your passwords for any number of possible uses; or anyone who wants information you keep on your computer.

Am I really a target?

This is an important question to ask yourself because, in order to correctly determine the extent of the security measures that you need to take, you first need to consider the sensitivity of your data. After all, if an intruder infiltrates your computer and finds nothing but personal pictures and your collection of music, then there's little that they can gain; in such a case, extensive security measures would do little more than cost you money.

On the other hand, if you keep extensive financial and personal information that could be used to gain access to your credit lines or credit rating, then the stakes are higher. If you keep confidential work information on your home computer, you'll want to take all due steps to keep that information out of the wrong hands. Similarly, if you have information on your computer that would make it easier for people to invade other aspects of your life (even something as benign as the date of a wedding anniversary that you might have used as a PIN number), then you'll want to keep this information safe from prying eyes.

Passwords, your first line of defense

Anyone who's used a computer is likely acquainted with the prevalence of passwords. For many computer users, this is the extent of the security between their personal information and an intruder. To this end, it's important to get the most out of your passwords by considering a few ideas:

Make your passwords difficult to guess

Consider the last time you logged into your bank's Website. You probably entered a username and a password. How likely is it that someone would guess your password if they were determined to gain access to that site with your username? If your password is the same as your username or is something simple like the word "password," then consider this a bit like leaving a spare house key under the welcome mat -- it won't be difficult to find.

A strong password will contain a combination of uppercase letters, lowercase letters, numbers and other symbols. It will also be as long as you care to make it; nowadays, many sites require passwords to be at least six or eight characters long, but an even longer password will be even less likely to be guessed arbitrarily.

Don't leave your passwords where people can see them

"Strong" passwords, unfortunately, are a double-edged sword; if your password is long and contrived, then a would-be intruder may have a difficult time guessing it, but you might also not be able to remember it. It's common to write down your passwords, but keep in mind that if you write down a password and leave it near your computer, anyone who comes near your computer will be able to see your password as clearly as you can.

Find a balance between the strength of your passwords and how visibly you have to remind yourself of what those passwords are. After all, if you wrote down your ATM card's PIN and kept it in your wallet with your ATM card, then a lost wallet would likely lead to lost money. Avoid doing the same basic thing with your computer passwords.

Change your passwords as often as the security needs of your data warrant

If invaders are determined to gain access to your personal information, they may keep trying indefinitely until they get access. Changing your passwords regularly will confuse their efforts. But again, you need to balance this with the other ideas. If new passwords mean you write down the new password and leave it where someone can find it, then the security offered by a new password is limited. Also, if the password guards information that can't be used against you in any significant way, then your efforts to keep track of a regularly-changing password may wind up leaving you more exposed than would a simple password that you can easily remember.

Help guard your computer from intruders

Nowadays, many people's computers are always on and connected to the Internet. As long as this is the case, your computer is exposed to would-be intruders; of course, there are steps you can take to guard your computer.

Anti-virus and anti-spyware software

Anti-virus software has long been a staple in the world of computers. The prominence of the Internet has brought about the need for additional anti-spyware software to help protect against different kinds of threats.

Viruses and spyware are both malicious forms of software, but their aims are typically different. Viruses are programs that are often destructive to the data on your computer, although the goals of viruses may range from destruction to simple observation. Spyware, which is typically installed discreetly when you visit a malicious -- or, possibly, unknowingly infected -- Website, is generally meant to quietly observe, perhaps sending its reconnaissance findings to someone else. Either might lead to the theft of your personal information, possibly without you even being aware. Both are quite likely to lead to problems with your software, especially your web browser and operating system, which may be difficult to remedy without having to re-install the software. You can install security and utility software to help shield your computer from viruses and spyware.

A router can act as a powerful shield

Viruses and spyware have one interesting trait: They rarely get onto your computer without you inviting them, even though this may be completely inadvertent. After all, an unwanted pest that sneaks into your home when you open the door wasn't exactly "invited," but it nevertheless had to wait for an opportunity to gain entry.

Other types of threats don't have to be invited. These threats usually come from hackers, people looking to gain access to -- or control of -- your computer for whatever reason. First and foremost, keep your operating system up-to-date with the latest security patches; many hackers simply try to exploit the latest "known vulnerability" to gain access to your computer, and if you've already patched that vulnerability, then the hacker will have to look elsewhere.

The inexpensive routers designed for home use, such as a broadband router, nearly always perform a service called Network Address Translation (NAT) to let all the computers on your network share the one IP address that your Internet service provider gives you. NAT has an interesting side-effect: If an uninvited visitor, such as a hacker, attempts to contact your computer, the router that's performing NAT will simply fail to recognize the traffic as having been requested and will ignore it. For many people, a broadband router, as well as the requisite anti-virus and anti-spyware software, will provide all the security that their computers will ever need. Shop for routers, hubs and switches to help keep your home computer safe.

Firewalls and other devices

In computer terminology, a firewall is either a piece of software or a dedicated device that prevents unwanted traffic from passing. When you have a router running NAT, it's effectively acting as a firewall. You can also get a dedicated firewall, either as a piece of software or as a stand-alone unit, to ensure that no un-requested traffic ever passes the firewall and reaches your computer.

For the more security-minded, there are also options such as Virtual Private Network (VPN) devices and Intrusion Detection System (IDS) devices. A VPN device is used to create an encrypted connection between two computers or between computer networks. Both sides of the connection must be aware of the connection (meaning both must have VPN software or a VPN device), so this is only useful when you're able to install equipment or software on both sides of the connection. VPNs are often used to let telecommuters have a secure connection to the computer network at work, from their home computer or their laptop. IDS devices will monitor the traffic that comes into a network and attempt to identify possible intruders, such as a hacker who's attempting to discreetly probe for potential entry points into a network. IDS devices, however, are generally only useful if you must leave openings in your network, such as if you are a business that has servers that need to be publicly accessible.