Safe
Surfing
If you believe the AOL
advertisements on the TV you will think that the internet is a warm fuzzy place
full of nice interesting things to do. While the net certainly does contain a
lot of useful information and resources, the simple fact is that it mirrors the
real world in that it is also populated by people who aren’t very nice who
would rather like to do something nasty to you. In this article I want to
introduce you to some of the nasty things that go on and to provide you with
ways to protect yourself from them. Rather like Crimewatch, I don’t set out to
frighten you, just arm you with useful knowledge.
Inevitably some of what I want to say is a little technical but be assured,
I’ve kept it to a minimum – and I’ll explain everything.
IP numbers
So what can people find out about you
when you’re on the net? Well the answer is quite a lot. Go to http://www.sinc.sunysb.edu/cgi-bin/MyIP
to see what I mean. Every time you log on to the net, you are assigned a
unique 12 digit number called an IP number or address (for example
206.141.202.111) by your internet service provider (ISP). In some cases this
number is always the same but some ISPs issue different numbers each time. IP
number comes from a fixed block of numbers allocated to the ISP and can be used
by others to identify your ISP.
Because any site you visit can find out your IP number it can be used against
you. For example, you make a nuisance of yourself at a bulletin board, the
moderator could ban your IP number to prevent you accessing the board. Because
ISPs are required to keep records of who has which IP numbers allocated at any
given time, it is theoretically possible for you to be tracked down if you are
really bad. Don’t panic, however – I believe it would require a court order
to do this.
Who’s watching?
It is easy to imagine that when you are visiting the net you are simply looking
through a window and nobody can bother you. Wrong! There are people out there
who would dearly like to get into your computer and, with readily available
software, can do so. If you want to know how vulnerable you are visit Steve
Gibson’s excellent web site (https://grc.com/x/ne.dll?bh0bkyd2)
invite him to “test your shields” and “probe your ports”. It won’t
hurt a bit but, if you don’t have a firewall, will reveal how “naked” your
computer is.
What you need is a barrier to keep the unwelcome hoards out. Enter the
“firewall”.
A firewall is a piece of software which you run on your computer. It sits
quietly in the background not bothering you at all until someone tries to poke
into your machine. The firewall then stops the visitor and warns you. There are
several excellent firewalls on the market. I use Zonealarm. The good news is
that there is a free version of Zonealarm for home use. (http://www.zonelabs.com)
With Zonealarm active my PC is invisible to Steve Gibson’s web site.
Viruses
Everyone has heard about viruses and the internet is one of the easiest ways of
contracting them. Viruses are programs written by stupid or malicious people
usually to prove how clever they are but also often to cause damage. The simple
fact is that a good quality virus killer is an indispensable aid to safe
surfing. Again there are several good ones about. My own preference is McAffee
Virusscan (http://www.mcafeeb2b.com/default.asp). Unfortunately this is a
commercial product but it provides good protection and is updated most weeks.
Another quality product is Norton Antivirus (http://www.symantec.com/).
No matter how good your virus killer is, it must be supported by good computer
“hygiene”. Here are two key rules:
- Never
open or run an e-mail attachment unless you are 150% sure that you know who
has sent it and what it is. E-mail is one of the prime sources of virus
attack.
- Never
run a program unless you know that it is genuine or you have received it
from a bona-fide source.
e-mail
Everybody uses e-mail. It’s quick, easy and private. Did I say private? Sorry,
a typing error. E-mail is not private, in fact you should treat an e-mail as the
electronic equivalent of a postcard. Anyone can read it if they want to.
Don’t put personal information such as home address, telephone or credit card
details in an e-mail if you want to keep them private. After all, you wouldn’t
give such information to a stranger in the street!.
By the way, do you have a spare e-mail account to use when dealing with “dodgy
geezers”? While it’s fine to give your e-mail address to those you know and
trust would you give it to someone you don’t know? There is always a danger
that unscrupulous folk might start sending you unsolicited e-mails (spam) and
other junk mail.
The simple answer is to open a second account to act as a sort of post office
box which you give to those you don’t trust. If they then send spam to that
address there is no harm done. The best source of free e-mail accounts is
hotmail. (www.hotmail.com) It’s run
by Microsoft, easy to use and can be set up anonymously so far as third part
users are concerned. My spare e-mail account, for example, is
the_chinese_laundry@hotmail.com!! If someone started to spam this account, I
would simply forget about it and open a new one.
Spyware
Now this is sneaky stuff. Some characters thought it would be a good idea to
hide little bits of code into programs which, once the program is installed on
your PC, will feed information about your PC and surfing habits back. This is
called spyware. A free utility called Adaware is available and is designed to
find spyware on your computer and remove it. (http://www.lavasoft.nu/)
- I’ve used it and it works.
Cookies
No it’s not tea time. Cookies are small pieces of program which are put onto
your PC when you visit a web site. Their original purpose was to hold certain
information which would subsequently speed up future visits to the site. All
very laudable but unfortunately less altruistic people adopted cookies to act
rather like spyware. Depending on your browser, you can control cookies easily.
Also some firewalls allow cookie control. Alternatively you can use a small
program called Burnt Cookies to decide which cookies are allowed onto you PC. (http://www.andersson-design.com/bcookies/index.shtml)
Popups
Popups are new windows, frequently containing advertisements, which open when
you visit a web site. Mostly they are harmless but some sites open popups which
can’t be closed or spawn many
more popups if you try to close them. A nastier trick is that some web sites
will add bookmarks to your browser or will change your default screen. All these
tricks operate through small programs called Java scripts. If you know how, you
can disable java in your browser. I prefer to run a program called Popup Cop. (http://www.popupcop.com/)
It integrates nicely into Internet Explorer and can be easily adjusted to deal
with the most obnoxious web sites.
The
opinions expressed here are solely those of the webmaster who takes no
responsibility for the compatibility of the software described with any other
users PC or system.