Firewalls - the first line of defence01 July 2005
An Internet connection without a firewall is comparable to leaving your car unlocked with the keys in the ignition - without firewalls, your company's network of computers is constantly running the risk of coming under security attacks.
But what exactly are firewalls?
Essentially, a firewall is an actual barricade to keep harmful forces away from your property. It is a program or hardware device that filters incoming information from your Internet connection and prevents viruses from entering your computer and spreading.
They are essential for all businesses of all sizes and are particularly pertinent at this time in which reports are continuing to warn of rises in the volume of viruses, worms and Trojan horses causing havoc for UK businesses.
How do we implement firewalls?
Some operating systems come with a built-in firewall. For those that do not, either a software or hardware firewall can be simply downloaded or installed onto your computer.
Software firewalls are available through the Internet. This type sees your computer become a gateway as it provides the only point of access between your business network and the Internet. Software firewalls are convenient and highly efficient tools that tend to be paid for monthly or annually.
Hardware firewalls are where the firewall unit itself is normally the gateway. Both types of firewall have similar high virus prevention rates although the hardware devices tend to be less expensive as they are purchased with one lump sum and rarely carry with them additional charges, like set-up fees.
Adapting our firewalls
Once installed, we can and should adapt the firewalls to suit the individual needs of our businesses. This can be done in a number of ways:
- Through specific text - we can set our firewalls to identify any specific words or text which are then rejected and blocked from entering our computers.
- Through IP addresses - firewalls can be set to block all traffic to or from an IP address found to be reading too many files from a server.
- Through domain names - firewalls can also be set to reject any domain names, which is simply the human-readable version of an IP address.
And finally...
Through protocol definition - it is also possible to set firewall filters to monitor several common protocols, ie the pre-defined way how the client and server interacts. These include:
- Internet Protocol (IP) - the principal delivery system for information over the Internet
- Hyper Text Transfer Protocol (HTTP) - web page practice
- File Transfer Protocol (FTP) - system in place for download and upload of files
- Transmission Control Protocol (TCP) - information reconstruction over the Internet
However...
While firewalls do tackle incoming viruses, they should not be relied on as the only anti-virus software installed on your computer.
It is always worth the investment to choose packages that include additional anti-virus software, such as BT's Internet Security Pack, that offer affordable yet reliable virus protection as well as top quality firewall software.
