What is a Firewall and Why Do They Matter?

Hearing “firewall” in the context of computing can be confusing.  This blog article aims to explain what a firewall is and how it will benefit your business.

In computing, a firewall sits between your internal network and the internet outside. It is kind of like a nightclub bouncer that allows the good people through while keeping the bad people out! . A firewall works in a similar method by preventing unwanted traffic from getting through.

The Packet Filtering Firewall Approach

A firewall can be hardware, software or a combination of both. A packet-filter firewall monitors and controls network traffic. It works by filtering data entering the network according to predetermined rules. IT experts set up a firewall to examine small amounts of data (called “packets”) to see if they contain threats. It checks packet data against criteria such as allowed IP addresses and packet type. If the data is suspect, the firewall stops those packets, if not, the data will be allowed to pass.

Firewalls stop certain software from sending and receiving data to and from the internet. This reduces the number of entry points for viruses or illegitimate traffic.

A firewall also monitors outgoing traffic. Why is that? Because an infected computer may be “phoning home” to activate or download a further payload or other malware.

By contacting it’s “master” the malware strengthens the bad guy’s ability to attack victims.

Firewalls can help prevent denial-of-service (DoS) attacks. In a DoS incident, thousands of computers are used to send an overwhelming amount of traffic to a network. It’s like having 100,000 people trying to enter a store built for 20 people all at once!

Previous attacks have targeted business big and small so no one is immune.

Other Types of Firewall

Packet-filtering firewalls aren’t your only option. Stateful inspection is helping to make firewalls even smarter. These check where the packet came from, where it is going, and what application requested it. This end-to-end examination is more rigorous. All the parameters must match trusted information for the packet to pass through. This approach offers a smart, fast way to inspect for unauthorized traffic.

When setting up any firewall, it is important to avoid any unintentional openings. A hole in a chain link fence renders perimeter security useless. A hole in a firewall leaves your network vulnerable.

Need help deciding on the right type of firewall for your business or want to be sure your firewalls are going to withstand attack? Our experts can help set up and test your firewalls. Contact us today at 08 8326 4364 or at support@dpcomputing.com.au!

Leave a Reply

Your email address will not be published. Required fields are marked *