7. Software protection

Firewall

A firewall is a program or hardware device that filters the information coming through the Internet connection into your personal computer or into a company's network.

It is set up to allow mainly one way access, i.e. you can go out onto the Internet and access pages, but it checks everything coming back against a set of rules. If the data coming back is from an unauthorised source, then it is blocked.

You may have heard people saying, 'I can't get on that site at school because it's been blocked'; that is the firewall in action.

Anti-virus software

This is special software which is used to detect viruses and to limit their damage by removing them.

The software tries to detect viruses before they can get access to your computer. If a virus is detected trying to get through the firewall, the software will give an alert and ask how you want to respond.

It is important that anti-virus software is updated regularly by going to the manufacturers site. Although the software was up-to-date when you bought it, within a few weeks, new viruses will have been released which your software won't know how to detect.

The manufacturers provide downloads to make sure that your software can identify all of the latest threats.

It is also important to run an 'anti-virus' scan regularly, just to make sure that there aren't any viruses lying dormant on your system.

User IDs and Passwords

When you log onto your network at school, you have to type in your User ID and Password. This identifies you to the network as an authorised user.

Any sensible company will ensure that staff need a User ID and Password to gain access to the system. This should reduce the risk of outsiders being able to get onto the system and damage data.

People should follow rules when choosing their password:

- passwords should be kept secret at all times

- passwords should not be something that is easy to guess such as pet's name or favourite football team.

- passwords should include text and numbers or symbols

- passwords should be a reasonable length e.g. over 6 characters

- passwords should be changed regularly

Encryption

This is a method of scrambling data in such a way that only the people who have the 'secret key' to unlock the message can read it.

This is an example of ordinary text:

Humpty Dumpty sat on a wall.

Humpty Dumpty had a big fall.

This is what an encrypted code for the text would look like:

lj86ik,£lj)ay%9w2+m?lsild171724

jkd2f*hkdfh7$171kjfh7d1h4d

You obviously have to keep the "secret keys" safe from prying eyes.

Audit Log

A very good way of tracing back a problem is for the system to keep an audit log.

This means the computer will record every important event in an 'audit file. It records who saved what and when. Who deleted records or changed them. For example an audit record may look like this:-

User: bigears233

File: TheMostImportantFile.doc

Changed: 3rd January 10:15am

(or Deleted, or Saved).