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Security vulnerabilities are found in most operating systems and software applications face security threats on a regular basis.
Many of these are minor but some can be more serious e.g. the 'Code Red' worm exploited a vulnerability in the Microsoft Office application and infected systems worldwide.
A constant stream of patches, hot fixes and service packs is provided by vendors of software and operating systems to fix or 'patch' vulnerabilities as they are identified. You can use this section to find out more about:
If you are using a recent Microsoft Windows operating system and visit http://v4.windowsupdate.microsoft.com/en/default.asp, you can obtain a list of relevant patches which will enable you to determine those that have not been installed on your own system. You can choose to install some, all, or none of these, as you see fit. R
unning updates can take some time because you may need to download relatively large files, however it will be time well spent. When you run the Windows update for the first time, it is likely that there will be many files to download. However, if you subsequently update your system on a weekly basis the process will become much faster as there will be fewer items to view.
Remember that every patch has been created to fix an identified vulnerability - if you choose not to install one, your system will remain at risk from that particular threat.
Virus defence software should be installed on all elements of your computer system - for example, on:
Installing this software will certainly help to protect your systems against virus attacks, however the level of protection is greatly reduced if you do not keep it up to date.
New viruses and worms are emerging all the time and you can keep up with them only by installing updates as they are released by your anti-virus software company. These updates are usually for virus signatures or for the virus software itself.
Every virus has its own binary pattern which is known as a 'virus signature'. This is unique and can be used to identify a virus, rather like a fingerprint. For example, a characteristic of the 'Love Bug' virus was that it included the text 'love letter' in the subject line of the e-mail. As such, this text was a signature for the 'Love Bug' virus.
Virus checking software contains a library of virus signatures. When the software scans a file, it checks for any patterns that exist in its library and reports any matches as an infection. Virus defence software companies are continually updating their signature libraries. Each new virus is analysed to identify its characteristic byte pattern (signature) and, once found, it is added to the signature libraries.
It is therefore important to ensure that your virus defence software is updated regularly - typically by downloading the latest signature files from your vendor.
This is quite easy as most anti-virus software packages have either a 'live update' option (so that your libraries are checked and updated each time you connect to the Internet, or at set intervals) or an 'update now' option (which checks for updates when you select them). These updates are usually quite fast (even without a broadband link) because the signature files are relatively small.
Most virus defence software updates are in the form of updated signature (or pattern) libraries. However, actual software updates can also be required. As viruses become more sophisticated it is sometimes not enough for vendors just to update signature files - they also have to update how their software searches for them. Software updates take longer to download than signatures because the files are much larger. Although this kind of update tends to be infrequent, it is an essential task.
As with signature updates, your software package may provide a 'live update' or an 'update now' option. Alternatively, you might find that updates are posted on the website of your virus defence software vendor so you should check this regularly.
In the case of a single computer, it is relatively simple to keep software and patches updated. Maintaining multiple systems can prove to be more of a challenge, but with careful management it can still be straightforward. To update a number of computers you can:
In either case, try to download the updates systematically. To do so all at once may clog up your Internet connection.
If you have a Local Area Network (LAN), one of the best ways to download updates is to use just one machine (for example, the file server) and then schedule other servers and PCs to connect to this machine for their updates.
In such a case you would still need to check that each computer has been updated successfully. For example, if the original download fails on the server, any error messages would be displayed on that server only.