Network Segmentation, Microsegmentation

VLANs Are Not a Microsegmentation Strategy—Here’s Why You Need to Upgrade

Published October 24, 2024 by Nicholas DiCola

Organizations are facing increasingly sophisticated cyber threats, and securing network infrastructure is more critical than ever. Traditional network segmentation methods like VLANs (Virtual Local Area Networks) and ACLs (access control lists) were once effective. But much has changed since the advent of this technology in the 1980s, and VLANs and ACLs are no longer sufficient in protecting modern network environments. While VLANs once provided adequate security, they now struggle to address the complex security challenges posed by modern attackers.  

Enter microsegmentation—a more in-depth, granular approach to network security that stops lateral movement and prevents attackers from breaching critical systems. 

It’s time to understand why VLANs and ACLs are outdated and how microsegmentation, especially with Zero Networks, is the future of network protection. 

What Are VLANs and Why Are They Outdated? 

VLANs, or Virtual Local Area Networks, were first created by W. David Sincoskie in 1984. Sincoskie developed the first VLANs after trying to figure out how to break through bottlenecks to scale up capacity. VLANs are designed to segment network devices into smaller, logical units, allowing network administrators to improve efficiency and manage traffic, mainly to manage broadcast domains. Traditionally, VLANs have been used to group devices based on factors like function, location, or department. And while they’re still valuable for controlling network traffic and reducing congestion, VLANs fall short when it comes to security. 

VLANs operate by dividing a network into segments, which theoretically isolates different types of network traffic, but they rely on static boundaries and manual ACLs to limit traffic between them. Over time, as networks evolve, these static rules get poked full of holes, and as a result, create security gaps. These gaps are where cybercriminals thrive, allowing them to move laterally across the network once they gain access to one segment. With today’s sophisticated attackers constantly finding new vulnerabilities to exploit, VLANs no longer provide the necessary level of protection.  Since VLANs don’t limit traffic inside the VLAN, lateral movement between devices inside the VLAN has no limitations! 

Furthermore, VLANs and ACLs are notoriously difficult to maintain. As organizations grow, so does the complexity of their network infrastructure. Maintaining VLAN boundaries requires constant manual updates and configuration changes, which introduces operational overhead and increases the likelihood of security misconfigurations. 

Microsegmentation: The Evolution of Network Security 

As organizations look to strengthen their cybersecurity postures, microsegmentation has emerged as a superior alternative to VLANs. Microsegmentation goes beyond the broad strokes of VLANs, providing fine-grained controls that protect individual applications, workloads, or even processes. This level of precision ensures that even if an attacker breaches one part of the network, they are effectively contained and unable to move laterally to access other sensitive areas. Here at Zero Networks, we like to refer to this as the “leave hackers stranded” tactic. 

While VLANs group devices and apply uniform policies, microsegmentation enables organizations to enforce strict security policies based on specific behaviors and access requirements. For example, instead of grouping devices based on location or function, microsegmentation allows you to control access at the application layer, ensuring only authorized users can interact with specific processes or data sets. 

Zero Networks’ microsegmentation solution takes this approach even further by automatically generating security policies for every device and network connection. With no manual configuration required, Zero Networks' microsegmentation adapts dynamically to changes in the network environment, providing real-time protection without the operational burden. 

Why VLANs Can’t Prevent Lateral Movement 

Lateral movement—when attackers move across a network after gaining initial access—is one of the most dangerous threats to modern organizations. Once inside, hackers can navigate laterally to compromise critical systems, escalate privileges, and access sensitive data. VLANs, which rely on static network boundaries, are simply not equipped to stop these attackers. As network environments continue to become more complex, the weaknesses of VLANs are becoming increasingly apparent. 

While helpful in organizing network traffic, VLANs are not designed to stop an attacker who’s already inside the perimeter. They don’t provide the necessary controls to prevent unauthorized users from accessing different segments of the network once they’ve compromised one part, which poses significant security risks. 

Microsegmentation, however, addresses this issue head-on. By applying strict, identity-based policies that control which users or devices can interact with specific applications and systems, microsegmentation ensures that lateral movement is impossible—even if credentials are compromised. Zero Networks enhances this with real-time visibility into network traffic, ensuring that every interaction is monitored and controlled. 

How Microsegmentation Aligns with Zero Trust Principles 

The Zero Trust security model, which operates on the principle of “never trust, always verify,” is closely aligned with microsegmentation. Zero Trust assumes that threats can come from both outside and inside the network, meaning that no user, device, or connection is trusted by default. This model calls for strict access controls, real-time monitoring, and continuous validation of users and devices. 

 

Microsegmentation enforces these Zero Trust principles by allowing organizations to create highly granular security zones within the network. Instead of trusting users or devices based on their location within the network (as VLANs do), microsegmentation ensures that only verified users with specific permissions can access certain parts of the network. Zero Networks’ microsegmentation solution applies this concept by continuously validating the access rights of users and enforcing least-privilege access

Additionally, Zero Networks offers multi-factor authentication (MFA) at the port level, adding another layer of security to the microsegmentation approach. With MFA, even if a hacker gains access to valid credentials, they cannot move laterally within the network without additional authentication. 

Benefits of Microsegmentation with Zero Networks 

While VLANs may still be useful for certain networking tasks, they are no longer a viable option for comprehensive network security. Microsegmentation offers multiple advantages over VLANs, including: 

  • Granular control: Unlike VLANs, which group devices based on broad criteria, microsegmentation allows organizations to enforce security policies at a much finer level of detail. With Zero Networks, security policies can be applied to specific applications, workloads, and processes. 
  • Dynamic adaptability: Microsegmentation adapts in real-time to changes in the network environment. As new devices, applications, and users are introduced, Zero Networks automatically adjusts security policies to ensure continuous protection. 
  • Enhanced visibility: With VLANs, organizations often lack visibility into the east-west traffic within their networks. Microsegmentation provides deep insights into all network interactions, allowing security teams to quickly detect and respond to anomalies. 
  • Ease of management: Zero Networks automates the complex process of configuring and managing security policies, drastically simplifying microsegmentation compared to traditional VLANs. With Zero, organizations can reduce operational complexity and experience up to 83% cost savings when compared to traditional segmentation methods that rely on hardware firewalls. This streamlined approach allows for quicker deployment and easier ongoing management, all while enhancing security without the overhead typically associated with legacy solutions. 
  • Compliance and audit readiness: Microsegmentation with Zero Networks simplifies the process of demonstrating compliance with industry regulations, including DORA. By providing granular control and detailed visibility, organizations can easily prove adherence to security policies during audits. 

VLANs vs. Microsegmentation: The Future of Network Security 

As cyber threats evolve, it’s clear that relying solely on VLANs for network segmentation is no longer enough. While VLANs offer basic segmentation, they lack the granularity, adaptability, and security required to defend against modern threats like lateral movement. Microsegmentation, especially when implemented through Zero Networks' innovative platform, offers a dynamic, precise, and scalable solution for securing today’s complex network environments. 

By embracing microsegmentation, organizations can create a more secure, flexible network infrastructure that’s equipped to handle the evolving challenges of modern cybersecurity. It’s time to level up from VLANs and embrace the future of network security with microsegmentation.