Does it seem to you that protecting your PC from nasties such as viruses, spyware, adware and the like has got more complicated? Well you’d be right. So you have two options now, click off this page and consign that niggling doubt to the back of your mind or read on for a few simple paragraphs and gain a much clearer understanding of what threats there are and the simple inexpensive steps to take for piece of mind.

OK, good choice. Lets start. What are the threats? Simply you can get infected from opening an email, surfing the web, inserting a floppy disk, cd, USB memory stick. The different types of malware – that’s a technical term for any code that when executed does something disagreeable to your PC without your consent, are basically these

• Virus
• Worm
• Trojan Horse
• Rootkit
• Spyware
• Adware

A virus …

is in common parlance an over arching term to describe any kind of infection but this is nowadays superceded by the term “malware”. More specifically a computer virus is a program that can copy itself and infect a computer without the knowledge or consent of the user.

A worm…

is a self replicating computer program, that uses the network (ie internet) to propagate itself. It does not need to attach itself to a program to be executed, and hence can spread without human intervention. Worms typically cause harm by eroding bandwidth and slowing networks to a crawl whereas a virus typically alters or destroys something on the target computer.

A Trojan horse …

is not a virus as it does not replicate. It is a program that opens up “back doors” to the target computer. Note that a virus can comprise a Trojan, in that the virus “spreads” the Trojan across the internet. The term comes from the Trojan war where the Greeks built a large wooden horse, as a peace offering for the Trojans. Once the Trojans accepted the gift and took it inside the city walls the payload inside was the Greek army who then sacked the City. A decent firewall would prevent a Trojan from opening up any back doors and this is discussed in more detail here.

A rootkit …

is a program designed to take “administrator level” control of your system. They are the most difficult to find as they hide themselves away from the operating system. One common place to hide is the MBR (or master boot record) of the hard disk. This sector executes before Windows loads, the rootkit loads first and calls the shots. Rootkits typically comprise Trojans, allowing would be attackers access to your system through “back doors”

A Spyware infection is ...

a piece of code that was surreptitiously installed on the target PC by exploiting a known security flaw, or by “piggybacking” on desirable software which you download and install. These are typically picked up while surfing the web unwittingly. These programs gather information about you such as personal information, surfing habits and even key presses – useful for the bad guys if you type in your passwords to secure sites such as online banking. This information is then “beamed back” to the bad guys for the obvious purpose of their intent. Some rogue anti malware programs pretend to be security software while being spyware themselves.

An adware infection is …

A program that automatically plays, displays or downloads advertising material to your computer. Some types of adware comprise spyware also.

OK so that’s the basics covered, and before you rip the power cord out of your pc and run for the hills lets talk about the basic steps to a more secure system and peaceful night’s sleep.

In our experience, machines that have been infected have invariably been infected from the internet. Typically Mum and Dad use the machine for writing letters, checking the bank accounts and playing mahjong. When the kids grow up, they use social networking sites, peer to peer file sharing programs and this is where the fun starts. It might gladden you to know that modern operating systems support more than one user account, and that each user account can be “locked down” to limit the range of options available to that user. So Mum and Dad can have full administrator privileges, while the kids user accounts can be more restrictive. Also modern NAT routers often comprise internet access time zones, so you can banish surfing between certain hours of the day. This is a wider topic that is discussed in another article.

So the basic steps you need to take are :

• Make sure you are running behind a NAT router
• Make sure you have a reputable anti virus program installed, which is set to auto update its virus libraries. Test that this does auto update successfully.
• Run a rootkit scan often. For XP use Sophos anti rootkit, and for Vista use F-Secure Blacklight. Also use an adware scanner such as AdAware, or XSoftSpy SE.
• Prove your firewall using a firewall checker such as Shields Up, at www.grc.com

For added protection run a software firewall such as ZoneAlarm. Zonealarm is quite verbose when first installed and needs to learn your usage patterns, but once it has its rule table built eg MS Messenger is allowed to access the internet, AVG antivirus is allowed to access the internet then is settles down.

Some anti virus programs comprise all of the above, and can be a simpler solution for a small fee. Once such is AVG Internet Security. The anti virus program is free, whereas the internet security suite is less than a restaurant bill and is a one stop shop for all the malware mentioned at the start of this article.

And beware installing “toolbars” in internet explorer. These often allow malware in through security exploits. If you have toolbars installed then remove them.

And finally, if you want to try another approach, run a Linux operating system such as Ubuntu .Viruses for Linux are few and far between so you lower your risk of infection greatly.