What are firewalls?
18th February 2025
75% of businesses have implemented firewalls on their networks* – are you one of them?
To understand what a firewall is, I am first going to define the two words that firewall consists of:
A wall is a structure designed to provide shelter, be it from environmental factors or from people. It is meant to keep whatever is behind the wall safe and secure.
Fire is produced when a material reacts with oxygen, creating flames that can be very destructive, capable of burning things away.
A firewall combines the defensive nature of the wall with the destructive capabilities of fire to give your IT systems the best protection from any malware that may try to breach it. Here is how they work:
Packet Filtering: firewalls inspect packets of data as they attempt to pass through the network. Think of it as being stopped at security at the airport: they allow the packet through if it is deemed safe and block it if it is not, based on rules such as source, destination IP addresses, port numbers and protocols.
Stateful Inspection: tracks the state of active connection and makes decisions based on the context of the traffic, ensuring only legitimate packets are allowed through – no suspicious items allowed!
Proxy Service: firewalls can make requests on behalf of the user, inspect the responses and then forward the data on.
Next-Generation Firewalls: these more advanced firewalls have more features including deep packet inspection, intrusion prevention systems and application awareness. To continue the airport analogy these firewalls are newer airports with better scanners.
Firewalls are an effective line of defence against cyber security threats. Talk to your IT service provider to see if you have firewalls installed, or contact us if you would like any more information.