Computer security principles and practices

Computer Security

In the past few years, viruses like "I Love You" and "SoBig" have generated much publicity and apprehension and highlighted problems of computer security. In the last month alone, experts estimate that 52 new viruses have spread through computer networks. In addition, the growing incidence of identity theft also illustrates the growing sophistication of hackers and their tools.

This paper examines the main problems related to keeping the information on one's computer safe and secure. The first part of the paper looks at the main threats to computer security, both at home and in larger networks. These include hackers and infected files.

The next part then discusses the steps computer users need to take to protect themselves from such attacks, from simple steps such as periodically changing passwords to installing elaborate firewalls.

Types of Viruses

Breaches in computer security usually take the form of infected files. The most basic of these infected files is the "virus," a string of computer code programmed to replicate itself. Most viruses enter one's computer through e-mail attachments. However, viruses can also be spread through Web pages (Evarts).

Similar to the virus, the "trojan" often appears an e-mail attachment with a misleading title. Users unwittingly launch the trojan when they click on the attachment (Evarts). Often, the trojan also launches the computer's e-mail program, sending itself as an attachment to all the e-mail addresses in a user's address book.

The computer worm is more malicious than the simple virus. While a virus needs to be activated by a user, a worm can crawl in and out undetected while a computer is connected to the Internet. The most dangerous recent worms have already caused "denial of service attacks" that slowed down the Internet and even deleted data on a person's hard drive (Evarts).

In addition to infected files, many computers are also vulnerable to intrusions. Skilled hackers can break into a system and steal passwords, credit card numbers, social security numbers and other pertinent confidential information. This stolen information can then be used to steal a person's identity.

Protecting computer networks

Most experts agree, however, that taking simple precautions can prevent many virus and hacker attacks. The simplest precaution is to be careful in opening e-mail attachments. Many viruses and trojans replicate themselves through a computer address book. Therefore, users should not assume a file attachment is safe even if it comes from a familiar e-mail address (Seltzer 83).

Also, users are advised to change passwords constantly. Many people have the same password for a variety of sites, from Internet access to bill payment sites and online bank accounts, further facilitating identity theft. The most secure passwords have at least seven characters, with a mix of letters, numbers and symbols (Seltzer 83).

Computer users can also consult a variety of Web sites to keep abreast of the latest information on infected files. The McAfee web site, for example, provides up-to-date information regarding new viruses and a glossary of infected files and their effects. This site can be accessed at http://us.mcafee.com/virusInfo/default.asp?id=glossary.

Experts also stress the importance of a virus software program that is regularly updated, both among home and office users. This program should be installed on every computer in the network. Furthermore, computers running on the Windows 2000 and Windows XP platform should install the critical software fixes from the Windows Update service of Microsoft (Wildstrom 18). Users of the Microsoft Outlook e-mail program should also make sure they are using the updated version, which has patches for the program's numerous vulnerabilities (Seltzer 83).

Many computer security experts also ask users to invest in firewall software. Similar to the physical firewalls built to keep a blaze from spreading to other buildings, a computer firewall starts its protection at the point where a computer connects to the Internet, ideally keeping hackers and known infected files at bay (Wildstrom 18). Firewall technology works best in conjunction with an anti-virus program that is regularly updated.

Firewall technology is now standard among office network. As extra security, many offices have physical firewalls, meaning a dedicated computer acting as a gatekeeper for the rest of the network. However, many home users remain unprotected and vulnerable. For those who cannot afford to purchase a firewall program, several free versions can be obtained from SyGate (www.sygate.com) and ZoneAlarm (www.zonelabs.com).

While anti-virus software and firewall technology are the most important blocks, there are also other options available to enhance computer security.

Many free spyware blocker programs, for example, will search through a computer's cache, deleting tracking cookies that companies and hackers can use to track an individual's Internet usage or even steal personal information (Wildstrom 18).

However, despite such procedures, computers will invariable remain vulnerable to attacks. Firewalls, for example, do not protect against infected programs from file-sharing networks like KaZaA. Furthermore, many firewalls such as Microsoft's Internet Connection Firewall (ICF) also block legitimate file transfers.

ICF thus also prevents users on the same network to swap needed files (Wildstrom 18).