For businesses most of the investment revolves around computer networks. Businesses use it for ordering, inventory and accounting. Security of computer network is very important. Virus, spyware, worm and ill-intention employee can cause a big loss.



First step is to identify vulnerabilities, always keep up to date your operating systems and applications. If you are using Microsoft products, always check for new patch and service pack. 


Always keep back up of your critical data and create boot disk. Restrict physical access to you network computers. Make a policy for employee to use strong passwords.


If your computers are connected with internet install anti-virus software, firewall, spam filer and restrict transfer of confidential data via email, instant messages. Although Microsoft operating systems like windows server, XP, Vista and windows 7 comes with built-in firewall but still have vulnerabilities, it’s always better to install third party firewall software.Adobe have lot of security vulnerabilities, so don't forget to install the latest patches from Adobe. 


Web browsers are more vulnerable than any application, always keep them up to date, block automatic ActiveX control installation, try to avoid ads-on.


Prevent pop-ups and spyware from flooding the computer networks. Webroot Spy sweeper is a good choice to get rid of spywares.


Always train your user to never open attachments if they don’t know the sender. Never try to run application if they are not sure about it. Also disable hidden file name extension for known files.