A firewall is a security protocol that protects your internal network from the threats of the internet. It keeps an eye on the data that comes in and out of your home network. Without a firewall, your trusted private network could be at risk of cyberattacks, data breaches, and malware from the public. 1 RingCentral RingEx Employees per Company Size Micro (0-49), Small (50-249), Medium (250-999), Large (1,000-4,999), Enterprise (5,000+) Medium (250-999 Employees), Large (1,000-4,999 Employees), Enterprise (5,000+ Employees) Medium, Large, Enterprise Features Hosted PBX, Managed PBX, Remote User Ability, and more The technical side of what a firewall does To get to grips with how a firewall works, you need to understand how data travels between internet networks. Basically, data moves across the internet in the form of information-filled packets. A firewall inspects these data packets to analyze their: Content: The information each data packet contains, such as an image, text, or video. Protocol: The language of the data packet, for example, HTTP or TCP. Port: The medium that the data is traveling through, such as email, web, or a social media network. Source: Where the data is coming from, for example, the IP address or hostname of incoming traffic. Destination: Where the data is headed, including the IP address, hostname, and other information that describes where the traffic is going. Afterwards, the firewall determines whether to let the data packet pass or, instead, to block it based on a set of predefined rules. To ensure that dangerous data packets are blocked, it’s crucial that you properly set up your firewall, create effective rules, and keep it up to date. SEE: Learn the fundamentals of computer networking. Hardware firewalls Hardware firewalls are dedicated physical devices, often integrated into routers or standalone appliances, that act as a barrier between a private network and the internet. They offer robust, centralized protection, making them ideal for organizations and businesses that need to secure multiple devices or high volumes of network traffic. Although they are typically more expensive than software firewalls, hardware firewalls provide scalability and consistent performance, protecting an entire network without relying on the resources of individual devices. Software firewalls Software firewalls are applications installed on individual devices to monitor and control network traffic at the endpoint level. They are included by default in most operating systems, such as Windows and macOS, and some routers also incorporate software firewall capabilities. These firewalls can be customized to block specific applications, filter outbound and inbound traffic, and provide alerts for suspicious activities. The specific capabilities will depend on what type of software firewall you are using. A Next-Generation Firewall (NGFW), for example, may provide tools for access control, intrusion prevention, advanced threat intelligence, and deep packet inspection. What a firewall does to protect your home network 1. Blocks unauthorized traffic To reiterate, a firewall blocks threats coming from restricted sources or ports. This means your firewall will block any data packets coming from a restricted IP address or website. It will also reduce your home network’s visibility to potentially risky protocols. Firewalls can also block data packets that have malicious content. Basically, firewall users can set predefined rules to give a firewall access control of their data. Based on these rules, the firewall will shut out intruders. For instance, parents may set rules in the firewall to deny access to certain applications or block out content based on certain keywords. 2. Defends against threats A firewall serves as a checkpoint for all data packets, so it protects your home’s internet system from several threats, including: Cyberattacks coming from hackers who want to damage your system or steal and erase data. Malware that infects not just software but also hardware, possibly destroying applications and devices. Ransomware that locks important files, seeking funds from you to release it. Instead of just sniffing out these malicious invaders, a firewall neutralizes them in case they do enter your network. This way, it prevents the threats from spreading through your network infrastructure, further decreasing the scope of the damage. Learn more about the latest threats to network security and how to defend against each one. 3. Prevents application intrusion Even if you expect untrusted applications to act out of line, sometimes your most-trusted apps will try to access and extract sensitive data from your device. This can happen when the application is outdated, infected, or a hacker tries to use it to get into your system. Thankfully, your firewall observes an application’s behavior to make sure there are no attempts to enter unauthorized resources. Doing so, it protects your sensitive data. For example, if an application tries to access a location or photos on your device even though you haven’t allowed it to do so, the firewall will act immediately to stop it. Along with protecting your data, it will also inform you of unusual activity. 4. Improves network performance Firewalls are more than security guards. Since they monitor the flow of traffic and keep an eye on who’s accessing your devices, they free up valuable resources. By doing so, they reduce network congestion and improve your performance online. Apart from filtering out unnecessary traffic volume, a firewall also keeps the network’s functioning in check by increasing your security. What’s more, firewalls prevent crashes that can occur due to cyber attacks, misconfiguration, or bugs in your system. 5. Maintains privacy Imagine a stranger watching you through your window. Creepy, right? This is something hackers may do to keep an eye on your data and browsing habits. They might even use your private information against you. A firewall stops this from happening by using rules to filter network traffic, blocking unauthorized attempts to access your system or monitor your activities. It inspects data packets for suspicious patterns, ensuring sensitive information stays secure. Advanced firewalls use features like deep packet inspection and stateful packet filtering to detect and prevent unauthorized data transfers or malicious activity. They also monitor outgoing traffic, stopping applications or malware from transmitting private data to