What are 9 Types of Firewalls and Their Functions

There are several common types of firewalls, such as packet-filtering, circuit-level gateway, and application-level gateway. Each type of firewall has unique specifications and functions to address different security issues.

The main function of a firewall is to monitor and control network traffic based on predetermined security rules. Understanding each type can help you choose the right firewall according to your network security needs.

This article provides an in-depth look at each type of firewall and how they work. You will find useful information to ensure the security of your network.

1. Packet Filtering Types of Firewall

Packet-filtering firewalls serve as the first guard in a network security system. These firewalls work by checking data packets entering and leaving the network based on predetermined rules.

This method is effective in intercepting suspicious traffic before it reaches the internal network. Consequently, packet-filtering firewalls are reliable for basic data filtering needs.

The right time to use it:

• Best used for small to medium networks.
• Suitable for basic filtration.
• Used when there is a fundamental need for data traffic security.

2. Circuit-Level Gateway Firewall

Circuit-level gateway types of firewalls work at the transport layer by monitoring TCP or UDP sessions. They protect internetwork connections by approving them before data is transferred.

The way this firewall works is by allowing connections that are considered safe through verification. As a result, circuit-level gateway firewalls are appropriate when connection monitoring is needed but with higher efficiency.

The right time to use it:

• These types of firewalls applied when connection monitoring is required.
• Ideal for organizations with many session-based connections.
• Used in environments that require high efficiency without in-depth inspection.

3. Application Level Gateway (Proxy Firewall)

A proxy firewall is a firewall that acts on behalf of a user in network transactions. Therefore, this firewall not only protects users from external threats but also maintains privacy and reduces information leakage.

Proxy firewalls provide high security by filtering data down to the application level, ensuring that each request is secure before it is forwarded.

Additionally, this firewall is suitable for networks that require a higher level of security with strict user control.

The right time to use it:

• Perfect for application-level protection.
• Used when data privacy is critical.
• Applied in environments that require tight user control.

Also Read: What is Dynamic IP? Benefits and How to Use Dynamic IP

4. Network Firewall

A network firewall is a system that protects the entire network at the point of entry. We typically use this firewall for large-scale networks that require comprehensive protection.

The way a network firewall works is by managing access to and from the internal network, utilizing filtering and monitoring techniques. Thus, using a network firewall is a recommendation for networks with a high level of complexity.

The right time to use it:

• Applied to large networks with complex settings.
• We use it when we need a complete protection.
• Suitable for organizations with extensive network architecture.

5. Hardware Firewall

Hardware firewalls come as hardware that processes network traffic and provides additional physical security. These firewalls are physically installed at network access points to monitor and filter data traffic.

The main function of a hardware firewall is to prevent unwanted access by providing additional protection in addition to software. The use of hardware firewalls is optimal for networks that require physical security and large capacity.

The right time to use it:

• Used for enterprise networks that require large capacity.
• Perfect for those who need additional physical security.
• Suitable when there is a lot of physical access to the network.

6. Firewall Software

Firewall software is an application installed on an individual device for local network security. This firewall offers flexibility because we can customize it to the specific needs of an individual device.

Firewall software inspects packet data in detail and provides direct protection to the device in use. This firewall is ideal when we prefer individual protection for each device.

The right time to use it:

• Applied to personal or small devices.
• Suitable for individual device protection.
• Ideal for situations requiring customization to suit device usage.

Also Read: How to Fix Blue Screen of Death on Windows

7. Stateful Inspection Firewall

Stateful inspection firewall combines the attributes of packet-filtering firewalls and circuit-level gateways. This technology is more sophisticated by recording the connection status and considering the context in decision-making.

This firewall ensures that the data received is a response to a legitimate request, increasing resistance to attacks. Thus, it is effective in situations where dynamic security is required.

The right time to use it:

• Used when dynamic security is required.
• Suitable for organizations with diverse threats.
• Applied to systems requiring context-based protection.

8. Next-Generation Firewall

Next-generation firewalls (NGFW) are an evolution of traditional firewalls with more advanced capabilities. In addition to offering a deep inspection package, NGFW includes threat prevention and application control.

This firewall combines security with advanced analytics capabilities for better monitoring and protection. Therefore, NGFW is recommended for networks that require high threat detection and application control.

The right time to use it:

• Used in organizations with advanced security needs.
• Suitable for advanced monitoring and analysis.
• Ideal when we require high threat detection.

9. Cloud Firewall (Firewall as a Service)

Cloud firewalls, or firewalls as a service, integrate network security into cloud-based services. This firewall offers flexibility and scalability and can protect without geographical limitations.

The way cloud firewalls work is by providing continuous protection through integrated cloud services. The use of cloud firewalls is appropriate for infrastructure that prioritizes agility and cost efficiency. As such, it is ideal for organizations that need scalable and flexible protection.

The right time to use it:

• Deployed in cloud-hosted environments that require scalability.
• Suitable for infrastructure that prioritizes cost efficiency.
• Used when speed and flexibility are essential.

Do You Know All Types of Firewalls?

That’s a review of the types of firewalls and their respective uses. Understanding each type of firewall helps in choosing the right solution to protect your information technology infrastructure.

Each type offers a unique approach to filtering and inspecting data traffic. By now, you should know all the types. So, which one do you choose?