Stateful vs. Stateless Firewalls: Differences Explained

Of the many types of firewall solutions that can be used to secure computer networks, stateful and stateless firewalls work on opposite sides of the spectrum. While stateful inspection firewalls dig deep into incoming data packers, their stateless counterparts only monitor the static information of the communication, such as the source and destination of the data.

When it comes to choosing the right type of firewall and protection for your network, there are multiple factors you should take into account. However, the first step always remains to fully understand your options, how they work, their pros and cons, and whether they fall within your financial and technical capabilities.

Continue reading to learn more about the differences between stateful and stateless firewalls, as well as examples of both offerings.

For more information, also see: Why Firewalls are Important for Network Security

Stateful vs. Stateless Firewall: Summary 

Stateful Firewall

Stateful firewalls are a network-based type of firewall that operates by scanning the contents of data packets, as well as the states of  network connections. It’s often referred to as dynamic packet filtering or in-depth packet inspection firewall and can be used in both non-commercial and established business networks.

This type of firewall works on the 3rd and 4th layers of the network. In the Open System Interconnection (OSI) model, those represent the network layer and the transport layer, overseeing the movement of data traffic and communications requests made by users and devices throughout the network.

Stateless Firewall

Stateless firewalls are also a type of packet filtering firewall operating on Layer 3 and Layer 4 of the network’s OSI model. However, they aren’t equipped with in-depth packet inspection capabilities.

Stateless firewalls strictly examine the static information of data packets exchanged during cross-network communications. They constantly monitor the traffic for the sender and recipient’s IP addresses, communication ports, and protocols, blocking any traffic that doesn’t meet the network’s security standards.

On a related topic, also see: Top Cybersecurity Software

Stateful vs. Stateless Firewall: Features

Stateful Firewall Features

Despite operating differently from the traditional firewall software, stateful firewalls are about a decade more recent than the original firewall technology and carry additional features, capabilities, and tools to the basic firewall features.

Some of the most notable stateful firewall features include:

• Network-level Policy Enforcement: A stateful firewall is capable of setting up and enforcing security and policies for activity on the 3rd and 4th layers. It enables you to manage the data transfers between hosts and network components, and control the method and ports that forward the data packets to the network’s receiving devices and accounts.
• Dynamic Packet Filtering: While packet monitoring solutions filter traffic based on superficial qualities, such as the source and receiving end, stateful firewall technology monitors and tracks the traffic of an entire connection session. 
• Self-teaching Intelligent Capabilities: Stateful firewalls can get accustomed to the traffic and threat of a set network after some time. A part of the system’s memory is dedicated to retaining and retrieving the key differentiators of safe and malicious traffic that grows with time.
• High Traffic Capacity: Stateful firewalls are capable of performing with impressive speeds and qualities even under heavy traffic flows on larger networks. They can’t be easily overwhelmed by high-traffic attacks and are still able to correctly detect and intercept forged communications attempts and unauthenticated users.

Stateless Firewall Features

Stateless firewall technology is capable of rapidly supporting network security through the scanning of static packet information.

By approaching security differently, stateless firewall solutions generally come with features and capabilities that aid them in their work, such as:

• Control of Packet Flow: Stateless firewalls enable you to oversee and manage the data flow of network connections occurring on the third and fourth layers of the OSI.
• Centralized Filter Control: The security policies and filtering requirements of a stateless firewall can be drafted and enforced throughout the network from a centralized location.
• Large Scale Traffic Blocking: Network traffic originating or heading toward a set address can be blocked for either security purposes or better rationing the network’s bandwidth.

For more information, also see: How to Secure a Network: 9 Steps 

Stateful vs. Stateless: Advantages 

Top Stateful Firewall Advantages

There are many benefits to implementing a stateful firewall as your primary network protection solution, some of which include:

1. Highly reliable at detecting forged communication attempts
2. Minimizes the number of ports open for communication requests
3. Built-in, high-detail activity logging, and analysis
4. Centralizes network communications and traffic management
5. Highly intelligent and grows to better fit your network

Top Stateless Firewall Advantages

There are many advantages to using a stateless firewall to secure the components of your network in the face of evolving cyberattacks, such as:

1. Delivers fast results without causing the system to lag
2. Withstands large and consistent flow of data packets and traffic
3. Minimizes costs from implementation to required system resources
4. Doesn’t use up a lot of memory storage
5. Capable of protecting internal network components from insider attacks

Stateful vs. Stateless: Disadvantages 

Top Stateful Firewall Disadvantages

Despite its numerous features and advantages, using a stateful firewall solution as the sole network security precaution comes with a handful of cons that you should be aware of, such as:

1. Data transfers speeds are static and generally slow
2. More susceptible to Man-in-the-Middle (MITM) attacks
3. Takes time to become custom-fit to the security needs of your network
4. Doesn’t operate on the application layer, or 7th layer
5. Requires high memory storage and computational power to run at full capacity
6. Can be tricked into allowing unauthorized connections or data packets access to the network

Top Stateless Firewall Disadvantages

Relying solely on a stateless firewall for all the security needs of your network can be detrimental to the safety of your network. Stateless firewalls fall short in a handful of ways when used alone, such as:

1. Doesn’t inspect data packets in depth
2. Requires a lot of initial configuration to work properly
3. Unable to make connections between connected signs of an attack
4. It’s susceptible to attacks through spoofed IP addresses and falsified communications requests

On a related topic, also see: Top Cybersecurity Software

Stateful vs. Stateless: Examples of Providers

Examples of Stateful Firewall Providers

There are numerous stateful firewall solutions available on the market from a number of security software and service providers. They vary in reputation, efficiency, and the variety of added features and capabilities.

A couple of examples of stateful firewall providers include:

Palo Alto Networks

Palo Alto Networks is a Santa Clara, California-based network and cybersecurity company that provides a highly-diverse portfolio of cloud, platform-based, and native security solutions to organizations.

Palo Alto’s Next-Generation Firewall (NGFW) is a stateful firewall that’s capable of managing and monitoring the network’s layer on the 4th layer, but also traffic match and application on the 7th layer.

Microsoft Azure

Microsoft Azure is a Redmond, Washington-based networking and cloud computing service and product provider by Microsoft. It offers several application management, security, Microsoft-managed data centers, and network management solutions.

The Microsoft Azure Firewall is a cloud-based, intelligent network firewall that offers protection to the data and workloads taking place on the Microsoft Azure cloud environment. It’s fully stateful in configuration and comes with pre-installed high capacity and availability that can be scaled in the cloud without a limit.

Examples of Stateless Firewall Providers

While stateless firewall solutions are generally less popular among organizations with high-security needs for large networks, the technology plays a primary role in securing enclosed networks that don’t handle a lot of traffic at a reasonable cost. 

Following are a couple of examples of stateless firewall providers:

Cisco Systems

Cisco Systems is a San Jose, California-based digital communications, security, and computing networking company. It designs, develops, and sells software and hardware to help organizations better manage and connect their networks through secure devices and proper data management and analysis.

The Cisco UCS B-Series is a family of networking servers that incorporate Cisco’s network security and data management standards. The devices support abstract and stateless capacities, allowing for a more varied network security experience.

Forcepoint

Forcepoint is an Austin, Texas-based software company that provides security, data protection, cloud access, and networking solutions to businesses and organizations. It’s most known for its cross-domain firewall and network security solutions.

Forcepoint’s Next-Generation Firewall (NGFW) protects from data theft and prevents unauthorized access and communications within and outside of your network. It’s equipped with both stateful and stateless packet filtering capabilities, allowing it to protect a wide range of network architectures.

For more information, also see: Data Security Trends

Bottom Line: Stateful vs. Stateless Firewalls

At the end of the day, both stateful and stateless firewall solutions have their benefits under the right circumstances.

While stateful firewalls inspect individual connections made outside the network, seeking signs of malicious web traffic, and can learn to become better at detecting threats, stateless firewalls are more basic in their approach.

In contrast, stateless firewalls only monitor and inspect the metadata and outwardly displayed information of a packet to determine whether it poses a threat to the network.

Each solution may be the best for your business – depending on your unique infrastructure needs.

For more information, also see: What is Firewall as a Service?