Firewall’s: A Beginners Guide
We’ve all heard of them, most of us have got one – but what on Earth is a firewall?
Firewalls are an extremely important line of defence from cyber attacks either to your home or business network. If, for some reason, you don’t have a firewall set up, then you should stop what you’re doing right this second, head online and install one immediately – you can continue reading this blog when you’ve finished.
Why Is a Firewall So Important?
Without a firewall, any amount of malicious malware, worms, Trojans, or anything else could completely freely come waltzing into your machines and cause all sorts of havoc and damage.
Any computer that is connected to the internet is a potential target for cyber attacks. We all tend to go online and do whatever it is we like to do without worrying about things too much. And this carefree attitude that most of us seem to manage to embrace is, actually, quite remarkable. I’m serious – the internet is a constant threat to us all. To our livelihoods, our savings, our businesses, even our identities. There’s no natural virus in the world that can strip us of any of those things. Yet there have been people – evil geniuses – who have, over the years, invented digital demons that can break into the very building blocks of our organised lives and steal us completely away.
When you stop to think about it, it’s terrifying. But, for the most part, we don’t. Such is the rapidity of the modern world that we never stop to think about any of it. We carry on, sharing our lives and our details with the world on Facebook, hand over millions and billions of pounds every year on e-commerce sites, send our personal health information to the doctor over email, we bank online, we pay our taxes online, we even order pizzas online.
And at any moment, one of those digital demons can rear its ugly head and strike us down.
But, do we care?
Well, because most of us have been smart and invested in some internet security, which we believe is happily ticking away, slaying all of those demons and dragons in the background. And it will be.
Even if we don’t quite understand it all, most of us will still nonetheless be using some sort of anti-malware or anti-virus software, hoping that it will be keeping us safe. And, yes, it is very important to have those defences up to date and installed on your connected machines. But, there’s one other thing that you need to make sure that you have in place as well, and that’s a firewall.
How Does It Work?
Let’s put that question another way…
What Is a Firewall?
That’s better. Well, first – take a look at this basic diagram of a firewall in action from Microsoft.
In simple terms, a firewall is essentially a piece of software (or indeed hardware) that sets up a kind of border between your computer and the internet. When any pieces of information want to cross this border and come into your home or business computer, then they must first go through some very quick but important cross-border checks, which are performed by the scrupulous security bots that make up the firewall. If these pieces of information are deemed to have the appropriate passports, visas and other documentation, then they are allowed across the border and into your computer. If they don’t, or if they are otherwise deemed to contain any form of SPAM or other malicious content, then they’re sent packing.
Firewalls are important, because they are designed to prevent worms, SPAM, Trojans, viruses, malicious software and even hackers from gaining easy access to your computer. They monitor everything that comes in, and, importantly, as all good cross-border security should do, they monitor with equal rigidity everything that tries to go out as well.
This is an extremely important function of the firewall. Sometimes a machine may become compromised within the firewall – this may be by some malevolently-minded individual who has actual physical access to your computer and has managed to hack into it, or possibly by some remote party or worm that has managed to wriggle into your network undetected (firewalls, unfortunately, like everything else can never be 100% effective 100% of the time – occasionally something will get through).
Either way, when this happens, then the intention may be to use your machine as a launch pad from which some sort of SPAM or malware may be skyrocketed into cyberspace and sent on its wormy way to infect as many machines as it can physically/digitally encounter. But, your firewall will get a second chance here where it can redeem itself. For, anything that is sent out of your computer and into the web waves is scrupulously checked for SPAM and other malware as well. If any email, message, or anything else that you try to send out fails the cross-border checks, then it simply will not be allowed to leave your computer. Brilliant, really.
And that, in a nutshell, is the basics of the firewall, what it does and why we all need one. Firewalls are the first lines of defence for a lot of computers and networks. And for good reason – they’re effective. So set one up right now if you haven’t already, and start burning down those digital demons at the borders before they get a chance to come in.