From Wikipedia, the free encyclopedia

This article provides tips on how to make sure you can be safe on the Internet and how to keep computer viruses, malware, and other unwanted software off your computer.

Contents 1 Basics 1.1 Routers 1.2 Firewalls 1.3 Anti-virus 1.4 Anti-spyware 1.5 Browser choice 2 See also 3 External links 4 Sources of security-related software free for personal use 4.1 Firewalls 4.2 Spyware blocking, detection and removal 4.3 Antivirus 4.4 Browser Add-on

Network Address Translation (NAT) typically has the effect of preventing connections from being established inbound into a computer, whilst permitting connections out. Getting a router in your home improves the security of a home LAN; some people consider that they don't need a firewall if they have a router. However, for a small home network, software NAT can be used on the computer with the internet connection, providing similar behaviour to a router, and similar levels of security but for a lower cost and lower complexity.

A firewall blocks all traffic except through authorized ports on your computer, thus restricting unfettered access. A stateful firewall is a more secure form of firewall, and system administrators often combine a proxy firewall with a packet-filtering firewall to create a highly secure system; this would be overkill for a home system, but is more common in business. Most home users would use a software firewall, while some high risk servers and computers might need a hardware firewall.

Some bad people or companies write programs like computer viruses, worms, trojan horses and spyware. These programs are all characterised as being unwanted software that install themselves on your computer through deception.

Trojan horses are simply programs that conceal their true purpose or include a hidden functionality that a user would not want.

Worms are characterised by having the ability to replicate themselves and viruses are similar except that they achieve this by adding their code onto third party software. Once a virus or worm has infected a computer, it would typically infect other programs (in the case of viruses) and other computers.

Viruses also slow down system performance and cause strange system behavior and in many cases do serious harm to computers, either as deliberate, malicious damage or as unintentional side effects. In order to prevent damage by viruses and worms, you need either to completely isolate your computer from dangers (impractical for many people or networks) or install antivirus software, which typically runs in the background on your computer, detecting any suspicious software and preventing it from running.

Some malware that can be classified as trojans with a limited payload are not detected by most antivirus software and may require the use of other software designed to detect other classes of malware, including spyware.

Generally anti-virus software may be also be used to scan all of the files on a computer occasionally for extra peace of mind. Because of the continuing increase in the number of viruses and worms being identified, all good anti-virus software includes a facility to regularly update the data that is used to identify viruses. As well as the commercial antivirus programs, which generally require an annual subscription, there are free antivirus programs available, but the best commercial programs appear to be a little more reliable at present. Several companies provide a comparison of the performance of different antivirus programs which should be useful in making a decision as to which to use.

There are several kinds of threats:

• Spyware is software that runs on a computer without the explicit permission of its user. It often gathers private information from a users computer and sends this data over the Internet back to the software manufacturer.
• Adware is software that runs on a computer without the owner's consent, much like spyware. However, instead of taking information, it typically runs in the background and displays random or targeted pop-up advertisements. In many cases, this slows the computer down and may also cause software conflicts.

Internet Explorer is currently the most widely used web browser in the world [1], making it the prime target for phishing and many other possible attacks. This has caused some users to switch to different browsers, such as Mozilla Firefox, Opera, and Netscape.

• Computer network security
• Computer security
• Malware
• Internet privacy
• Identity Driven Networking

• Windows XP Security Software Microsoft's Security at Home - Free Downloads & Trials for Windows XP systems
• What are keystroke loggers? - detailed advice and information on keystroke loggers, and trojan horses, and how to remove them
• Security4web - detailed advice and information on Internet security for individuals and families
• SecurityBay - security news, articles and vulnerability database for security-aware Internet users
• DeBog - Security and safety help for non-technical users

• Spyware Blaster
• Spyware Guard
• Spybot Search and Destroy
• Ad-Aware (Lavasoft)

• Avira
• Avast Antivirus [2]
• AVG Free edition
• ClamWin - Opensource Antivirus for Microsoft Windows

• PwdHash is a Firefox & IE browser extension that transparently converts a user's password into a domain-specific password.
• Firefox Privacy/Security FoxyProxy, Password Hasher, Torbutton