Monday, April 24, 2006

Protecting your computer

Whenever you connect your computer to Internet, your computer is exposed to millions of different attacks. The result of these attacks could be infection with new viruses, adwares / spywares, stealing your personal information, stealing your identity, sending spam, using your machine as source of attack on other machines on Internet and worse.

If your have broadband Internet connection, you are even more vulnerable to all those attacks as your computer is connected to Internet all the times.

What are these attacks?

The attacks to computer are done in several different ways.

Virus

Malicious small programs that easily replicate themselves, infect your computer, and often spread to others' computers via email attachments or network traffic.

Virus programs can delete files, format disks, attack other computers or just make your system run slowly. They can also create a "back door" that allows a hacker to run programs on your computer or to access into your files.

A computer infected with a virus may suddenly act in unexpected ways. For example, it may take longer to access files or to start up programs, or it may lock up often. You may also notice uncommon sounds being played from your speakers, a variety of images popping up on the screen, or problems starting your computer. These are all signs that your computer could be infected with a virus.

Phishing

The term "phishing" (pronounced "fishing") refers to a form of fraud that uses e-mail messages that appear to be from a reputable business (often a financial institution) in an attempt to gain personal or account information. The e-mail message typically includes a link to a fake Web site that appears identical to a legitimate page. The fake Web page is used to collect the requested information. This information is then used for fraudulent purposes.

Once personal or account information is obtained, "phishers" may access your bank or credit card accounts, open new accounts in your name, or cash counterfeit checks on your account. For more information, see Identity Theft.

Spyware

Spyware is software that gathers information about your Web-surfing habits for marketing purposes. Spyware "piggybacks" on programs you choose to download. Tucked away in the fine print of user agreements for many "free" downloads and services is a stipulation that the company will use spyware to monitor your web habits for business research purposes.

Spyware takes up memory and space on your computer. It can slow down your machine, transmit information without your knowledge, and lead to general computer malfunction. One of the most widely-used Web browsers, Internet Explorer is especially susceptible to spyware-related problems. You may choose to keep certain spyware programs on your computer in exchange for the free services that accompany them, but you should be aware of how that might affect your computer.

Adware

Adware is a component in software applications that displays ads while the program is running. For example, adware is included with web-based email programs that give you free email in exchange for viewing ads. Adware "piggybacks" on programs you download from the Internet. Tucked away in the fine print of user agreements for many "free" downloads and services is a stipulation that the company will use adware to post advertisements on your computer.

Adware takes up memory and space on your computer. It can slow down your machine, transmit information without your knowledge, and lead to general computer malfunction. You may choose to keep certain adware programs on your computer in exchange for the free services that accompany them, but you should be aware of how that might affect your computer.

Spam

Spam is unsolicited commercial email (from legitimate or illegitimate sources), recognizable by its suspicious subject lines and unexpected or unknown sender.
For the most part, spam is an annoyance. Spam often contains questionable content and may include attachments that contain viruses.

Identity Theft

Identity theft occurs when someone uses your personal information (i.e., your name, Social Security Number, credit card number or other identifying information) without your permission, usually to commit fraud or other crimes.

Daily activities such as writing checks, charging an item to your credit card, and forgetting to log off your computer system can increase your risk of identity theft. Victims of identity theft often have to spend lots of time and money cleaning up their personal and financial records. In the meantime, they may be refused loans, housing or cars, or even get arrested for crimes they didn't commit.

How to protect your computer

Use secure and more stable operating system

You should pick operating systems based on the priority sequence as shown in following list. Note Macintosh is not mentioned in following list because it installs only on Apple machines.

  1. Secure Linux: If possible use Linux (with enhanced security) OS.
  2. Windows XP: If you can not use Linux, then use Windows XP with internal firewall enabled.
  3. Windows 2000: Use Windows 2000 as last resort. Always install firewall and antivirus software before connecting your machine on Internet for first time.
  4. Absolutely no to Windows ME, Windows 98 or any predecessors.

Use antivirus software

Anti-virus software protects email, instant messages, and other files by removing viruses and worms. Anti-virus software downloads new virus protection updates to protect against new threats. It also quarantines infected files to keep a virus from spreading on your computer and can repair infected files so you can use them without fear of damaging your computer or spreading a virus to others. If you use windows based operating system, you should always install good antivirus software. Following are options of good antivirus softwares

  1. Norton antivirus
  2. McAfee antivirus

Keep antivirus software updated

New viruses are born and spread through Internet everyday. If your antivirus software's virus database is old, it will not be able to protect you from new viruses. You should regularly update virus definition for your antivirus software.

Install firewall

Regardless of operating system, you should have firewall enabled on your machine. Linux already comes with firewall, so you don't need to install any additional software but you should make sure that your firewall is enabled and configured correctly. Windows XP also comes with firewall but might not be enough to protect you from all attacks from Internet. You should always get additional firewall software for windows and install it on you machine. Following are the options of good firewall software

  1. Symantec/Norton Personal Firewall (commercial)
  2. McAfee personal firewall (commercial)
  3. ZoneAlarm (Free but very restrictive)

Install OS patches and updates

Always keeps your operating system updated. This applies to both Linux and Windows based operating systems.

Browsing Internet

Use Mozilla FireFox as alternative to Internet Explorer for browsing Internet. The FireFox provides several features (e.g. popup blocker) and extensions (e.g. adblock, spoofstick etc.) to block unwanted contents from Internet. It has less security holes compared to Internet Explorer. Firefox is also available for Linux and other operating systems.

Accessing Emails

Email Client
Use Mozilla Thunderbird as alternative to Outlook or Outlook Express for receiving or sending emails. The Thunderbird provides several features (e.g. popup blocker) and extensions (e.g. adblock, spoofstick etc.) to block unwanted contents in email. It has automatic SPAM filter. It support PGP plugin to encrypt your emails. It has less security holes compared to Outlook Express. Thunderbird is also available for Linux and other operating systems.

Encrypt emails
Use PGP (Pretty Good Privacy) to encrypt your outgoing emails. GPG (Gnu PG) is open source implementation of PGP and can be easily integrated with Thunderbird email client.