Computer viruses are the bane of business in the 21st century. Whether they are devised as malicious pranks or to prove one's manhood or whatever, viruses can literally bring a business to its knees. And, like so many things, the best defense is an aggressive offensive policy to stop them from ever entering your business.

There are a number of ways that viruses can get into your network: E-mail is one of the most common, as are malicious Web sites. They can also infect your network via external media, like floppy disks and burned CDs. Rounding out the list are unprotected Internet connections, such as your DSL or T1 lines and even wireless connections. So, you must be prepared to guard all of those avenues.

There are a number of different types of viruses. A Trojan Horse is a destructive program that pretends to be a harmless or fun program. Worms are programs that replicate themselves over computer networks and usually perform malicious actions. Viruses are programs that are loaded onto your computer without your knowledge and run against your wishes.

So, what can be done to thwart this invasion? A proactive defense strategy is needed. Your strategy should include several layers of security to defend your network from outside intrusion. And, the entire security plan should be part of a larger Data Protection Strategy aimed at minimizing the possibility of data loss due to internal accident or negligence and external tampering.

Firewalls are your first line of defense in protecting your data from outside influences. Available in several types, firewalls can be software and/or hardware based. Firewalls can usually be configured to keep out certain files.

Anti-Virus protection is an essential element of your internal defense. The major developers are Symantec, McAfee and Trend Micro (free online scan). The key to anti-virus protection is to keep the virus definitions current. The war against computer intrusions is truly a pitched battle, with the good guys countering the bad guys' last move and the bad guys then developing a new virus that avoids prior safeguards. So, keeping your virus definitions and fixes current is critical. Almost all software developers offer an anti-virus solution that can be centrally managed, so you can update users' definitions automatically.

E-mail filtering and limiting access to potentially malicious Web sites are other appropriate security measures. Some firewalls and separate software packages are available to assist in this regard. Additionally, you can set your Web browser for high security and educate your users so that they will not browse or download from potentially harmful Web sites. They should also be counseled to avoid opening spam e-mails or messages from unknown parties.

Network security is everyone's concern, because breaches usually become everyone's problem! <<

Sidebar: Best Practices

Each month, we'll provide proven Best Practices. Readers are encouraged to send along any successful IT management approaches they may be using. We will feature the best of them in upcoming columns.

5. Establish a Data Protection Strategy.

As covered in earlier columns, backing up your network data is essential to a good night's sleep! However, beyond backing up regularly, you need to have the system safeguards in place that protect your data from malicious or negligent losses. Your strategy should provide hardware and software specifications and configuration requirements, as well as usage guidelines and redundancies. It should also establish and control limitations on which personnel can either knowingly or unknowingly install programs, as well as monitor a strict password policy.

6. Train all users on the Network Use Guidelines.

Once all of your procedures and safeguards are in place, it's time to make sure all employees are on board with the system configuration and the controls and limitations placed on them. Most employees are generally aware of the dangers posed by viruses and will willingly comply with necessary controls. To make sure that they aren't unknowingly breaking the rules, it is critical that you review the dangers, the company's precautions and the limitations placed on them regularly. <<