Security is crucial in any hosting environment. A hosting service must ensure its servers are up to the latest standards to protect all hosted websites from cyberattacks. This is especially true if access is shared among different users, such as the case with Shared Hosting, for example.
Website owners, online businesses, in particular, must also protect their websites from malicious threats to avoid compromising visitor data or getting suspended by their service providers.
Firewalls are one of the most important defenses to safeguard your network, applications, and hardware devices. You can set it up on any server and computer. But, the diverse range of firewalls and their protection levels can be overwhelming.
In this guide, we’ll discuss the different types of firewalls to help you choose the most suitable one to protect your online project.
What Is a Firewall?
A firewall is a network security system or a hardware device that analyzes and filters incoming and outgoing traffic based on a set of predefined security rules.
You can set a firewall to prevent specific applications from sending out information, which reduces the risk of data theft. In addition, you can utilize this security method to restrict access to certain websites for other users.
How a Firewall Works
A firewall monitors and scans incoming traffic at your computer’s port/entry point that decides how external devices exchange data with each other.
Picture it as a security guard at the airport. His job is to physically inspect every individual trying to enter for weapons or any harmful objects before they’re allowed through the airport gates.
Similarly, a firewall acts as a shield between your internal and external network that allows or blocks traffic. It also protects your websites from malicious software and any potentially harmful threats.
Types of Firewalls
There are two main types of firewalls – hardware firewalls and software firewalls.
Software firewalls are programs you can download and manage from a single control panel, even though they are intended to secure an entire network. On the other hand, hardware firewalls require physical installation and periodic maintenance.
In most cases, both types are available for personal and enterprise use. For instance, your home router is a form of hardware firewall, whereas your operating system comes preinstalled with a software firewall.
Firewalls can be categorized into six types depending on their structure, features, and functionality.
Packet-filtering firewalls are the most basic type of protection. They rely on predetermined security rules to inspect data packets and prevent them from going through if they don’t comply with those preset conditions. They can block traffic from a certain IP or any address that is trying to reach a specific destination on your server.
The downside of packet-filtering firewalls is that they have limited analyzing capabilities. For example, if you open one port, the firewall will allow all traffic through, even if it seems illegitimate. In other words, it processes data packets without inspecting their content, making it easier for hackers to get in unnoticed.
Stateful Inspection Firewall
A step up from packet-filtering firewalls, stateful inspection firewalls can also analyze patterns of traffic flow based on state, port, and protocol. The firewall monitors all activity on a connection and keeps track of known and trusted packets. It only allows authorized data from the website or app and differentiates it from the one coming from suspicious sources.
A more advanced version of the stateful inspection firewall is the Stateful Multilayer Inspection Firewall (SMLI). It filters data packets at network, transport, and application layers. The firewall examines the passing information, compares it with trusted sources, and allows only what passes through all checks. This ensures that all communications take place from trusted sources.
Also referred to as Application-level Firewalls, proxy firewalls operate at the app’s level and only inspect data packets going in and out of a specific piece of software. They are mostly cloud-based and act as an intermediary between the server and end-user requests.
Still, some proxy firewalls are hardware-based and you can install them with the server. They use both stateful and deep packet inspection technology to analyze your data flow.
Proxy firewalls establish a connection with the traffic source and closely inspect the packets received. The only disadvantage of proxy firewalls is they can slow down your connection speed because all incoming data passes through multiple protective layers.
Network Address Translation (NAT) Firewalls
Similar to proxy firewalls, NAT firewalls act as an intermediary, but this time between several devices on a network and the outside internet. NAT firewalls assign a single IP address to the private network and hide the individual IPs of the connected devices to protect them from any targeted attacks.
All protected devices are hidden behind a protective wall and the system blocks any suspicious traffic coming their way.
Web Application Firewalls (WAF)
WAFs focus on filtering incoming and outgoing traffic from specific websites or web applications. They are able to defend against attackers taking advantage of vulnerabilities in your apps. Web application firewalls monitor HTTP requests, block any malicious requests, and filter out suspicious requests. This allows visitors to safely access your website.
Popular examples of WAF solutions include Cloudflare WAF, Sucuri Firewall, GoDaddy Firewall, and Incapsula WAF.
There are three main types of WAF – host-based, network-based, and cloud-based WAF.
Host-based WAFs can be fully integrated in the application software or the website. They are more customizable and less expensive than the network-based web application firewall. The only setback is that host-based WAFs are not very economical in their consumption of server resources and require some further maintenance.
Network-based WAF solutions are usually hardware-based. They are installed locally and minimize latency. However, network-based WAFs are the most expensive option that also requires storage and maintenance of physical equipment.
Also known as firewall-as-a-service (FAAS), cloud-based WAF is the most affordable option and the easiest to install and implement. The process is as simple as a DNS change to redirect traffic and you’re good to go. Since users pay monthly or annually for this security service, it has minimal upfront cost.
A cloud-based WAF usually updates regularly to protect your website against any new threats without any extra effort or costs on your end. The only drawback is that the user hands the entire responsibility of securing the website to a third-party, which can lead to problems down the line if they’re not professional enough.
Next Generation Firewalls (NGFW)
NGFW is one of the most advanced solutions on the list. It offers the same functionalities of all the previous firewalls combined, and adds even more. Unlike the previously mentioned options that inspect data packets as a whole, NGFW opens each one to analyze and filter out any malicious threats from going through.
Other features offered by NGFW include intrusion prevention, anti-malware, VPN, and encrypted traffic inspection.
Whether you’re a web hosting service or a website owner, a firewall is an essential component to protect your network from cyber threats. Now that we’ve gone through the different types of firewalls and their functionalities, you can decide on which type is right for your needs.
If you want to run a website, personal or business, you must carefully choose your hosting service and check the cybersecurity measures it takes to protect its environment. Even if your web host offers robust security – it’s always better to consider an additional firewall to protect your site.