Computer security part 2

In my last article I looked at some of the ways you can protect your computer against viruses and spyware.  In this installment I will take the subject further and talk about how to stop people accessing the information on your computer from outside and also what to do if everything goes wrong and your computer has to be reinstalled from scratch.

Every computer that is connected to the internet has its own address (called an IP address) and has numerous doors (or ports) than can be opened and entered which gives access to the computer and anything that may be inside it.  To use an analogy, a computer connected to the internet is like an office block.  People can enter the block and unless there is adequate security on the doors people can roam around the office and take away anything they wish from company secrets  to the contents of the safe.  Offices often use a security guard to check the ID of the people entering the office and some doors are locked to some people so they can’t enter areas they are not entitled to.

Computers can also have their own ‘security guard’ and this is called a Firewall.  The firewall checks any attempt to enter a computer and decides on whether access is allowed or should be refused.  This is possible because every piece of information that enters a computer (called a packet) has a label that says where it comes from and where it wants to go.  A properly set up firewall will decide whether the packet has the right to enter a door.

For those of us with Windows XP, there is already a firewall on our systems.  To access it, you go into the control panel and access the security centre.  Within this, you get various pieces of information such as whether your anti-virus software is up to date.  If you choose the ‘Windows Firewall’ and make sure it is turned on.  This is the simplest way of doing this and should be fine for most users.  There is a tab in the box called ‘exceptions’ which allows some programs to access the computer (such as antivirus etc.) and as long as there is nothing strange and unknown in there you should be OK.  Windows will ask you if you want to keep blocking a specific program if it tries to access the computer and unless you are sure you need the program to communicate outside of your computer you should choose to have it blocked.  Generally, if a program needs to access the outside world and you know what it is then you should choose to unblock it (Internet explorer, antivirus, anti spyware, email program etc.)  If you don’t recognize it then block it.  All incoming requests for information should be blocked automatically anyway if the firewall is turned on.

There are various other firewall programs out there from companies such as Symantec (otherwise known as Norton) and McAfee.  These programs often integrate with your antivirus program and should lock most attacks.

In the second part of this article I am going to look at how to prevent yourself from losing information and what to do if everything stops working and Windows has to be reinstalled.

A common misconception is that if it is stored on your computer it is safe and nothing else needs to be done.  However, it is highly likely that at some point your computer will stop working and will either have to be replaced or it’s hard drive (where everything is stored) will need to be wiped and ‘reinstalled’ with Windows and it’s programs.  Many people don’t worry about this until it’s too late and find themselves in the situation where their letters, emails etc. are lost and can’t be retrieved.  There are various ways of overcoming this so that all your personal information etc. can be saved.  Firstly, you could go to a professional ‘data recovery’ service that will take your hard drive and recover the information on it.  Sounds good yes?  Well it is in theory, but in practice it is very expensive so not really an option for the home user.  Secondly is to save everything onto floppy disks instead of the hard drive.  Again, sounds good; not only are your files safe if your hard drive breaks but they are also not stored on the computer in case your security measures haven’t worked.  The problem with this is that floppy disks can also be damaged (in fact very easily) and if this happens you will lose everything. 

Whilst I was teaching in Italy, we had school reports to write and many people preferred to do them on the computer at home and print them at school.  If we had 26 children in our class and were commenting on 11 subjects and other areas it would take a couple of weeks to do our reports.  Teachers would come into school with sets of five floppy disks that held the reports for the whole class and want to print them off on the last day.  Imagine their horror when they put the disk in the computer and the disk had stopped working.  Next, imagine their increasing horror when they asked me to get their information back and I had to inform them that unless they had another copy of the reports (hopefully on their computer at home) they would have to re write all the reports.  Quite often this is exactly what they had to do; and unfortunately they didn’t listen and made the same mistake year after year.

It is a good idea to keep copies of your files on floppy disk, but don’t just have them there.  Instead it is a good idea to have a regime of backup on the computer, and instead of using floppy disks, use CD’s.  Most home computers now have a ‘CD writer’ in them and blank CD’s are quite cheap.  Every week (or if you have done some important work immediately) copy the contents of your Documents folder to a series of CD’s.  For most people one CD would be enough.  If you use ‘rewritable CD’s’ you can probably get away with two or three CDs which you can rotate as you need.  Keep the CDs locked away in a drawer (not next to the PC just in case of fire or flood !) and you can be quite sure that things are safe. Even better, is to use the ‘Files and Settings Transfer’ program in Windows XP (I suggest this instead of the backup utility as it seems to offer a wider range of things to save).  You can find this by going to the Start button then programs then accessories and system tools.  When you are in the program, choose the types of files you wish to have backed up (don’t forget email! And Internet explorer favourites) and create the backup.  Afterwards just save to CD and you have an up to date backup of your system.

This has been quite an indepth look at firewalls and backup so I will leave it there for the moment.  If you have any questions or suggestions please get in touch on Richard@ictechinformatique.com or post in the forum here on The Languedoc Page. 

If there are any areas on computer use that you would like me to cover in future articles then please don’t hesitate to get in touch.  I write these articles to help you so if you let me know what areas you would like to know more about I can gear my articles to your needs.

Until next time….

Richard Cleverley