Security advice

Not so long ago, I encountered a supposed IT expert who stated categorically to one of my customers that anti-virus software was unnecessary because, in his words, “You only get viruses if you visit porn sites”!
I can assure anyone who reads this web log that what he said is NOT TRUE!
Whenever I look at the log on my e-mail server I can see that a significant number of viruses are intercepted every day.
A very high proportion of “spam” e-mails come complete with a virus, usually but not always as an attachment.
E-mail may be the most prevalent but is definitely not the only means of spreading viruses.
Recent research at the SANS Institute (see footnote), shows that on average, an unprotected PC connected to the Internet will become infected within 20 minutes. If you have a broadband connection, it's probably more like ten minutes. I have even come across of one case where a PC became infected within TWO minutes of its broadband connection being established.
Viruses are not the only problem. Keyboard loggers can steal your credit card details and passwords. Spyware can track each site you visit.

However, it's not all doom and gloom. There are steps that can
reduce the risks to acceptable levels.

First of all, make sure that all of the latest security patches are installed for your operating system.
That alone can keep a lot of attacks at bay. It is absolutely essential (and often forgotten) if you ever have to clear up after a virus attack...

Install anti-virus software.

If you are a home user, there is still a FREE program that you can download from Grisoft and it's very effective. The only slight drawback is that it doesn't always update its virus definitions automatically so you would need to update manually at least once a week, preferably more often.
Otherwise, any of the major brands will probably do a reasonable job, at least if you take some other basic precautions.

Install a firewall.

Again,there is still a free version of Zone Alarm that is probably good enough for anyone with a dialup connection.
If you are running Windows XP, and do not have a dedicated firewall installed, at the very least enable the built-in one as it's better than nothing.
I use Agnitum Outpost Firewall Pro throughout my network, even though I have PC configured as a dedicated firewall.
The dedicated firewall is just an old Pentium 100 running IPCop.
The rationale is that the firewall on an individual PC can stop infection spreading both in the local network and out to the Internet.

As an alternative to separate firewall and anti-virus packages, you can install a combined security package.
I use F-Secure Internet Security on my e-mail server (an old PC). It works very well and has the advantage of updating virus definitions automatically, sometimes several time per day.

Install a spam filter for your e-mail.

Some mail clients have basic spam filtering built-in but there are good, free specialist spam filters available such as K9 by Robin Keir that are more sophisticated and can be trained to identify spam and isolate it.

Install Ad-blocking software.

I use a combination of Lavasoft AdAware (free for home use), SpyBot Search and Destroy (yes these two can co-exist on the same PC!) and finally SpyWareBlaster.
Between them, they wipe out all forms of spyware.

If you have a broadband or even an ISDN connection that is always on, or you wish to share an internet connection over a network, you should consider a proxy server. Not only can you share a single connection but they usually provide extra features such as local e-mail, spam filtering and port blocking. The
last of these improves security a great deal. I can heartily recommend 602LANSuite which is free for up to five users.
Setting up a proxy server requires a bit of technical know-how but the results are worth it.

Another useful program from Agnitum is TauScan a dedicated tool for blocking Trojans, a type of virus that opens holes in the usual defences by attacking anti-virus and firewall systems. This opens the floodgates to all sorts of other viruses.

Finally, I cannot stress highly enough the importance of keeping security software up-to-date.
New threats emerge all the time and if your virus definitions are old, your anti-virus program will not recognise new viruses. It's just like a flu jab. You need a different vaccine for each strain of the flu virus.

And...I nearly forgot to add...Don't forget to regularly and frequently backup your data!

For further excellent advice on security and spam I suggest that you take a look at Julian Knight's website.

SANS
is the most trusted and by far the largest source for information security training and certification in the world. It also develops, maintains, and makes available at no cost, the largest collection of research documents about various aspects of information security, and it operates the Internet's early warning system - Internet Storm Center. The SANS (SysAdmin, Audit, Network, Security) Institute was
established in 1989 as a cooperative research and education
organization....Many SANS resources, such as the weekly vulnerability digest (@RISK), the weekly news digest (NewsBites), the Internet's early warning system (Internet Storm Center), flash security alerts and more than 1,200 award-winning, original research papers are free to all who ask.