The World of Firewalls
Chances are if you own or work with a PC you would have heard of the term “firewall”. Many PC’s come pre-built with firewall software and just work from the first time the PC is powered up, but how often do we actually stop to think about how they work and what they are used for? In this blog I hope to answer some of those questions.
Most of us now have fast internet connections in our homes or run small networks in our homes, without your internet connection being protected it will leave your PC and family vulnerable to offensive web sites and potential hackers. To help keep your network and PC safe you will need a firewall to protect you from these potential threats.
A firewall is a piece of software or hardware that will help filter the traffic coming through the internet connection to your network or computer. If an incoming packet of information is flagged as “potentially dangerous” by your firewall filters it is not allowed through to your network or PC. Firewalls are customizable which means the user is able to add or remove filters several different ways. Most firewalls will have a GUI (guided user interface) that you will be able to set these filters on. The most common filters used on a firewall are IP addresses, protocols and ports. Below are some examples of how these filters can be used.
IP Addresses – Each machine on the internet is assigned a unique IP address, a typical IP address will look something like (94.126.40.226) If your home network was getting too many files or connection attempts from an IP address not known by yourself, you will be able to set a rule to not allow any traffic into your network or computer from that IP.
Protocols – A protocol is a way that someone who wants to use a service talks with that service, protocols are often text based and will describe how a client and server will have their conversation. Some of the most common protocols are, HTTP, FTP, SMTP, POP and telnet. You may want your PC only to use certain protocols so you will be able to switch off those you do not wish to use.
Ports – Any machine or PC makes its services available to the internet using numbered ports. For example port 80 is for the web and port 21 is for ftp. If a particular hacker or malicious software is trying to access your system you will be able to block specific ports through your firewall to stop all inbound traffic or outbound traffic from a particular port.
I hope this has helped to shed some light on how your firewalls work and how important they are. Although you may not need to configure your firewall all of the time, it is important that we all run them to stay safe on the internet and make sure we have the latest versions of the firewall installed.
