When a computer connects to a network in an office for example, a world of working possibilities opens up to employees: sharing documents, messaging, instant access to data in other systems... In an office, the issue of security is not very problematic, as we are talking about an enclosed, generally closely-monitored environment.

Similarly, when you connect a computer to the Internet, the working possibilities are the same: share documents, access to information in any kind of computer, send e-mails to anywhere in the world. However, the Internet is always looked upon without considering its dark side. Since an Internet connection can provide access to information in a myriad computers, so maybe these computers can also access the information you have.

Generally, the process is not that simple, although for many hackers it can just take a few minutes, nothing more. Some basic safety measures can prevent the Internet connection from becoming a problem instead of an advantage.

The first thing to consider is that the main danger of the Internet at this moment is the proliferation of too many viruses. Even seemingly innocuous actions can carry with them the risk of infection. Have you received an e-mail? Well, with the infamous virus " I love you" you couldn't even trust a love letter. You want to browse the Web? There are many Internet servers with viruses in their pages (and not always unintentionally). Thinking of installing the latest free game everyone is talking about? It might contain a lovely Trojan Horse that, like its namesake, opens the door to attackers.


Besides the virus issue, which will be dealt with in more detail in another article in this series, while you browse the Internet, you actually receive lots of information in the form of files that stay in your computer. Most of these files pose no threat (see the section on cookies), but it's not always the case. For example, a web page might need to install a component on your computer to be displayed correctly. This can be a Java Applet (a small file with a program that carries out a certain action on your PC, like displaying an animation, a special effect or some web page feature), or an ActiveX control. These elements must be 'signed', that is, they must incorporate an authentication system guaranteeing that the content is the same at source and at destination. You should always reject an item whose signature is no longer valid or comes from an unreliable site, as it could have disastrous effects.



The much-maligned cookie.