Computer security guide: 3 defensive software

Security products can help protect your computer. Some are traditional packaged software, others are online services. Here are the types of security applications you are most likely to need:

Anti-virus

Designed to keep your PC free of infection, anti-virus programs generally use two different approaches. First, they match databases – known as signatures – against incoming files to spot potential threats and block them.

Vendors update signature files regularly, some run daily updates, others update signatures every hour or so. This isn’t always enough. Virus writers aim to ‘fly under the radar’ with fresh malware.

The worst codes spread faster than signature updates. So most antivirus programs now include tools designed to spot suspicious virus-like behaviour from unknown files. These files are flagged as potential threats and treated.

Anti-virus is a misleading name these days. Almost every anti-virus program provides protection from a range of different mal-wares.

Firewalls:

Firewalls control the flow of internet traffic to and from your computer. Some are hardware devices – if you use a router it may have a built-in firewall – but in most home set-ups they are software.

Firewalls have two main functions. They act as a gate, stopping unwanted traffic from entering your system. At the same time, they should stop unapproved traffic from leaving your system. For example, if there’s a spyware program on your computer monitoring your activities, a properly configured firewall will stop that information from being sent. Equally, if a worm infects your computer, a worm, a firewall will stop it getting out and infecting others.

The firewall in Windows XP only stops incoming traffic; so it will only protect you up to a point. You should invest in a commercial firewall product – they are all bi-directional.

Unlike antivirus programs, which are forgotten once install, firewalls are complex. If you set things up incorrectly, you may leave your computer vulnerable. Alternatively, you may hinder legitimate traffic – this is especially difficult if you use a home network. The best firewalls will automatically configure themselves, but they tend to err on the side of caution blocking any unusual application.

Anti-spyware

Also known as spyware blockers. There’s a thin line between antivirus and anti-spyware tools – in fact some commercial security products now combine the two functions in a single application. Good anti-spyware products will detect and remove both spyware and adware from your computer. It should also block this kind of software from being installed. Firewalls may detect spyware it first attempts to send data back to base.

Spam Filters

A program designed to stop, or at least drastically reduce, the amount of spam turning up in your email in-box. Spam filters can save you time and money sorting through rubbish emails but most home and small business computer users don’t need to worry about filtering spam. That’s because many ISPs and web-mail providers now use anti-spam filters to check mail before downloading it to your computer or read in your web browser. Also, modern email programs, like Microsoft Outlook 2007, have built-in spam detection tools.