What Is A Firewall And How Does It Work | Telehouse
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What Is A Firewall And How Does It Work?

Whether you’re a single computer user or the head of a multinational company, it’s vital to protect your data against hackers, fraudsters, malware and viruses.
The government’s 2017 Cyber Security Breaches Survey found that almost half of all UK companies had been affected by a cyber breach or attack in the previous year - for large firms the proportion was seven in ten. Cyber thieves will often target personal data which, if compromised, could damage a business and ruin its reputation.
That is why it is vital to invest in a good network firewall.

So, what is it?

A firewall is a barrier – or filter - that protects your computer system from potentially harmful activities. It separates a trusted network (your own) from untrusted networks (the rest of the internet).
It was named after the type of wall designed to prevent flames spreading around a building and can come in the form of a program, an item of hardware, or a combination of the two. Firewalls will flag up, and prevent, harmful connections.
Should there be any flaws in your existing IT security, a firewall will help uncover them in no time. Most commonly, it is placed between the router (connecting to the internet) and the individual or organisation’s network.

In basic terms, how does a firewall operate?

Once you connect to the internet, your computer receives packets of data – numerous individual units of information collected into a single package to allow them to travel through the network. The task of a firewall is to analyse these packets and decide whether they are safe to enter your IT system.
It can also prevent people within your network – employees and others – connecting to unsuitable websites and risking your security or legal problems.
There are several types of firewall, so let’s look at some of the most common ones.

Packet-filtering firewalls

Under this system, packets of data are checked against several filters. These can include specific words you think are risky - such as those associated with pornography or political extremism. They can also be filtered according to the IP address they came from (the numerical label given to the device that sent the data), and various other protocols (the common sets of rules that govern communications between computers).
A packet-filtering firewall looks at each data packet in isolation, rather than searching for connections between them.

Proxy-filtering firewalls

These types of firewalls look at the connections between the packets of data trying to get into your system. In other words, they analyse possible threats at a higher, broader level and monitor all activity between the opening and closing of a connection.

Next-generation firewalls

People who want to cause damage and make money from fraud are always looking out for new ways to infiltrate IT systems. According to the Office for National Statistics (ONS), there were 4.7 million UK cases of fraud and computer misuse during 2017.
Next-generation firewalls will elevate levels of security, helping companies to deal with malware and other higher-level attacks. They offer identity-based security as looking at IP addresses and protocols is no longer deemed adequate to deal with threats.
Next-generation firewalls continue to look at what is going on with data after the initial inspection is carried out.

The future of firewalls

Here at Telehouse we are committed to supplying the best security resources for companies. We supply fully managed firewall systems, so that your business can always be one step ahead of any potential threats or attacks. With more remote working and cloud-based IT, greater vigilance is required.
Our firewalls are fully integrated with other safeguards, providing maximum security and leaving you free from worry.
Talk to our team of experts on 0207 512 0550, or contact us via our website.