There are lots of ways in which you can become the victim of malware attacks. Using a firewall is one of the best shields against hackers attacks. You probably heard before that using a firewall is a must to strengthen your internet security. But what is a firewall exactly?
In this post, we’ll go over what is a firewall, how it works, and why you should use a firewall to protect your online security.
What is a Firewall?
A firewall is a security system that keeps an eye on all the network traffic (both incoming and outgoing) and decides what network packets to let in or out, based on a set of security rules. Simply put, the firewall acts as a shield between the internal network and the external network (such as the internet).
In places with more computers or devices, such as an office, there are internal networks and external networks (the internet). While the internal network is safe and trusted because only certain users get access to it, the external network is an open door for malicious attacks.
When you connect to the internet, you expose yourself to various risks. Besides the risk of downloading malware that will cause your computer to crash, hackers also get the opportunity to get hold of your computer and steal your private data such as your accounts credentials or even your credit card information. The firewall is the first defense layer to protect yourself from such threats.
Hardware vs software firewalls
A firewall network system can be either software or hardware.
Hardware firewalls – These types can be either firewalls built into the network routers or physical firewalls, and they protect all the devices that are connected to that network.
Software firewalls – These types of firewalls are programs installed on a specific device and monitor the network traffic only on that device. On Microsoft operating systems, starting with Windows XP, you’ll find a firewall already enabled by default. Although the Windows firewall comes in handy, it lacks more features than those purchased from antivirus software providers.
How does a firewall work?
To better understand how a firewall works, let’s go a bit over how your computer communicates with the internet.
The information travels between networks in the form of network packets. These packets contain information such as the source and destination address along with the data. Your computer receives these network packets through the entry points, called ports.
The easiest analogy here is to think about your computer as your house. The IP address is the address of your house, and the ports represent the rooms in the building. You only allow people you trust (source addresses) to enter your house (destination address). From there, the data is filter even further and only certain people have access to specific rooms. You, the owner, are allowed in all rooms (ports), but guests are only allowed in certain rooms (ports).
The firewall is the one that monitors all the network packets entering or leaving your computer, analyzes them, and decides which packets are trustworthy and which aren’t. The firewall filters unsecured and suspicious traffic based on a set of established rules.
Filtering data packets is the base of how a firewall works. The main thing a firewall looks at is the IP address of the source or destination. If the IP address fails to follow the security rules that have been established, the data packet is rejected so you’re protected against malicious attacks.
Modern firewalls software are more advanced and they can filter the traffic based on various criteria such as keywords, domain names, applications, and specific data ports.
What is the purpose of a firewall?
The main job of a firewall is to protect your devices from connecting to unreliable networks that could put your computer and personal information at risk.
Without any means to protect against attacks, you can, at any time, become a prey of hackers. There are numerous ways in which a hacker can get access to your computer or private information from downloadable malware and malicious sites to hacked WiFi networks. A firewall is able to spot some of these malicious actions and will block your computer from receiving data packets from harmful sources.
Firewalls also have other purposes. They are often used in workplaces and schools to block users’ access to certain websites or applications. The most common websites and apps blocked in offices and schools are social media platforms, YouTube, torrenting, and email clients.