IT Security

Different Types of Firewalls in Network Security Explained

What is Firewall and its Types?

A firewall is a network security device that monitors network traffic. The standard firewall definition shows that firewalls are systems that are put in place to provide network security. It does this by filtering out both in and outgoing network traffic – based on rules defined by the user. They reduce and in some cases, eliminate the occurrence of unwanted communications in the network, and at the same time, allow any genuine communication and information to flow in and out freely. Types of Firewall aren’t an option – they are essential for any business. They work hard to prevent attackers from accessing your servers and data maliciously.

5 Different Types of Firewall and Architectures

Circuit-Level Gateways

Circuit-level gateways are much like packet-filtering firewalls in that they quickly and easily check and approve or deny traffic. They do it without being heavy on resources, too. Circuit-level gateways work by verifying the transmission control protocol handshake. It doesn’t check the packet directly, so there is a risk of malware getting through. These are not the best ones to protect your business.

Stateful Inspection Firewalls

A combination of the two firewalls above, the stateful firewall inspection offer a higher level of protection for your business. The problem with these is that they take up more resources, which can slow down the legitimate packet transfer.

Proxy Firewalls (Application-Level Gateways/Cloud Firewalls)

A proxy firewall operates at the application layer as a middleman to filter incoming traffic between an end system and another end system.

If you want firewalls that operate at the application layer to filter traffic, proxy firewalls do the job. These are cloud-based most of the time, and they establish traffic connections and examine data packets coming through. The difference between these and the stateful inspection firewalls is that the proxy firewalls can also do a more in-depth inspection to check the packet contents. The drawback to these is that they can create a  network slowdown because of all the extra steps – but it’s all in the name of the security for your business.

Next-Generation Firewall

There’s no real insight into what makes a firewall today “next-generation” besides the time it was created. There are commonalities between these firewalls and the originals, and those include TCP handshakes and packet inspections. Next-generation firewalls also use IPS – intrusion prevention systems – to stop network attacks.

Pros and Cons of Different Types of Firewalls

Here is a comparative table of the pros and cons of different types of firewalls:

Type of Firewall	Pros	Cons
Packet Filtering Firewalls	Simple and fast Low resource consumption Basic filtering based on IPs, ports, protocols	Limited security features Cannot inspect payload data Vulnerable to IP spoofing
Circuit-level Gateways	Efficient at filtering TCP handshakes Protects at session level Lightweight and low cost	No deep inspection of packets Cannot filter specific application data Limited logging
Application-level Gateways	Provides deep packet inspection Can block specific applications Stronger access control	Slower due to in-depth inspection Resource-intensive Requires configuration per application
Stateful Inspection Firewalls	Tracks state of active connections More secure than stateless filtering Can filter based on context	More resource-intensive than packet filtering Vulnerable to certain DoS attacks
Next-generation Firewalls	Combines multiple filtering methods Intrusion detection and prevention Application-level control	Expensive High resource consumption Requires skilled management

3 Types of Firewall Delivery Methods

Software Firewalls

These are any firewalls installed on local devices. The biggest draw for these in that they can create a useful, in-depth defense path. Maintaining these on more than one device is not easy, though, so you may need more than one for each asset.

Pros

• Cost-Effective: Often more affordable than hardware firewalls, especially for small businesses or individuals.
• Flexibility: Easy to deploy on specific devices or systems. Configuration can be customized for each device.
• Granular Control: Provides detailed control over individual applications and processes on the host system.

Cons

• Resource-Intensive: Consumes system resources like CPU and memory, which can slow down performance, especially on older or less powerful machines.
• Device-Specific: Must be installed on each device, making it cumbersome to manage in large-scale environments.
• Vulnerability: If the host system is compromised by malicious code, the software firewall itself can be disabled or tampered with.

Hardware Firewalls

Hardware firewalls use physical appliances, and they act like a traffic router. The intercept data packets before they are connected to a network server. The weakness here is that they can be easily bypassed, which goes against your need for a firewall.

Pros

• Performance: Hardware firewalls offer high performance since they are dedicated devices that handle network connections without burdening other resources.
• Security: Isolated from the internal system, making them harder to compromise if a system gets infected with malicious content/ malware.
• Scalability: Ideal for protecting larger networks and can support multiple devices within an organization.
• Centralized Management: Easier to manage and configure in complex, enterprise-level networks.

Cons

• Cost: High upfront costs for purchasing the hardware and ongoing maintenance.
• Complexity: Requires expertise to set up and configure, especially for large-scale deployments.
• Limited Flexibility: Difficult to scale for smaller networks, as it requires physical space and regular updates.

Cloud Firewalls

Cloud solutions are also called FaaS – firewall as a service. They often go hand in hand with proxy firewalls, and the most significant benefit to these is that they grow with your business. They work to filter large amounts of malicious traffic away from your company internal network.

Cloud-based firewall protects your internal network from malicious attacks such as viruses, worms, Trojans, spyware, adware, etc. The cloud firewall also helps prevent unauthorized access to data stored in the cloud.

Pros

• Scalability: Easily scalable to handle high amounts of traffic, making it suitable for businesses of all sizes, particularly those that use cloud infrastructure.
• Remote Management: Can be managed remotely, offering convenience for companies with distributed teams or multiple office locations.
• Cost-Effective: Typically operates on a subscription model, reducing the need for expensive hardware purchases.
• Automatic Updates: Providers handle software updates and patches, ensuring the firewall is always up to date with the latest security measures and advanced threat detection techniques.

Cons

• Dependency on the Internet: A stable and fast Internet connection is required for optimal performance. Any downtime could affect the firewall’s operation.
• Limited Control: Depending on the provider, you might have limited customization options compared to hardware or on-premise software firewalls.
• Data Privacy Concerns: Storing traffic logs and other sensitive data in the cloud can raise privacy concerns, especially if the service provider is in a different jurisdiction with different regulations.

Which Firewall Architecture is Right for Your Business?

There is no need to be specific when choosing between firewalls. Multiple firewalls provide multiple layers of security.

You may want to think about these factors too:

• How large is the organization. How big is the internal networking? Do you need a firewall for each device, or one that manages the entire internal network? When choosing between software and hardware firewalls, these questions are important to consider. Furthermore, the choice between the two will largely be determined by the technical skills of the team responsible for managing the setup.
• The resource availability. Can you afford to place the firewalls on a different piece of hardware or even in the cloud? The number of outgoing connections the firewall has to handle and whether they are going to be constant also play an important role.
• The levels of protections required. The number and type of firewalls should be determined by the level of the network’s requirements for secure communications. Businesses that deal with sensitive customer information must ensure that their firewalls are secure.

What are Traditional Firewalls?

Traditional firewalls are software programs that prevent unauthorized access to computers connected to the Internet. They work by filtering network traffic based on IP addresses, port numbers, and protocols.

They prevent unauthorized access to a computer or network. A firewall creates security rules for incoming and outgoing traffic. For example, if you want to allow only certain websites to be accessed on your computer, you would create a rule that allows only those sites through the firewall.

Firewalls are used to protect against attacks from hackers, viruses, worms, spam, and other malicious software.

Firewalls have been around since the 1980s when the first personal computer came out. Today, there are many different types of firewall. Some are built into operating systems while others are stand-alone applications.

What is Private Network Firewall?

A private network security firewall is a software application that allows users to control which applications can access the Internet through a router. Private networks are used for businesses that want to restrict access to certain websites, such as Facebook and Twitter.

Which Firewall is Best for Your Business Needs?

Reading all of the different types of firewall can be confusing – especially as you have to choose which to use for your business. The real question you must ask yourself, though, is why you would only select one type of firewall. There is no such thing as a protected business with only one level of defense. You need to have more than one of these types of firewalls you want your business to remain intact. Cloud and hardware, individual software firewalls – it all works to cover your network. Once you identify your business needs, you can decide which firewalls will be best.

Why Does Every Business Need A Firewall?

Many small businesses think that they won’t need firewalls – after all, they’re only tiny outfits. The thing is, firewalls are not just created for larger companies. Every single business needs to protect itself from outside attacks. 60% of smaller businesses do not survive a cyberattack – which is why you need one.

Why Secure Firewalls Are Vital For All Businesses

Without a firewall, you put your business at risk of being hacked and having data stolen. If you do not want to take that risk, you need to do your research on the best firewalls for your business.

Summary

Firewalls are vital for every business. It doesn’t matter if you run a big corporation or a small mom-and-pop shop. Without them, your business could be subject to attack by hackers and other online criminals. That means you need to find out which firewall is best for your business needs.

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