Are firewalls obsolete in a zero trust network?

Haluk Ulubay
Haluk Ulubay
07 March 2024

cybersecurity landscape has evolved dramatically, with ZTNA emerging as the gold standard. This shift raises questions about the efficacy of traditional security tools, especially firewalls, within the zero trust framework. Our in-depth analysis explores the role of firewalls in legacy cybersecurity strategies, their challenges within ZTNA, their potential for adaptation, and the future of network defense in a cybersecurity epoch where implicit trust is a bygone concept.

The Role of Firewalls in Traditional Security Models

Historically, firewalls have been the cornerstone of network security, serving as a robust barrier between trusted internal networks and untrusted external networks. They enforced security rules to control traffic, positioning themselves as the gatekeepers of network perimeters. However, once this perimeter was compromised, firewalls traditionally allowed unfettered access within the network, exposing vulnerabilities in the network security framework.

Why Firewalls Fall Short in ZTNA

The rise of Zero Trust Network Access (ZTNA) has rendered the idea of a secure perimeter obsolete. Operating under the 'never trust, always verify' approach, ZTNA poses a significant challenge to the traditional firewall-centric security approach. Firewalls fall short in a zero trust environment because they lack the capability for ongoing authentication and validation of users and devices, which is crucial in addressing the sophisticated cyber threats of today. Additionally, firewalls find it increasingly difficult to manage security in the complex hybrid cloud environments that are integral to contemporary digital infrastructures.

Limitations of Firewalls in ZTNA

In the realm of ZTNA, the concept of security extends beyond the perimeter. It demands that every user, device, and network connection be continuously authenticated and validated. Traditional firewalls are not designed for this level of persistent scrutiny, which is essential for maintaining robust security in a zero trust framework.

Firewalls are also grappling with the challenges posed by encrypted traffic. As cyber threats increasingly exploit encrypted channels, the ability to inspect encrypted traffic has become crucial. Yet, standard firewalls are not inherently capable of inspecting encrypted traffic inline, which elevates the risk of cyber threats and potential data loss.

A critical weakness of firewalls is their ineffectiveness in preventing the lateral movement of threats within an organization. Should a user or workload be compromised, malware can rapidly propagate, inflicting considerable damage and undermining the integrity of the organization's cybersecurity defenses.

Adapting Firewalls for Zero Trust

Although they may have their limitations within the realm of ZTNA, firewalls are far from becoming obsolete. They can maintain a pivotal role in zero trust environments by evolving to meet the dynamic demands of this security model. This evolution is exemplified by Cloud Firewall, which integrates sophisticated capabilities such as application awareness, intrusion prevention systems, and identity-based controls. These advanced features enable firewalls to transcend conventional port-based restrictions, offering nuanced visibility and control over network traffic.

Navigating the Transition to Zero Trust

Implementing a Zero Trust Network Access can seem overwhelming, yet with meticulous planning and the right tools, organizations can effectively make this transition. The initial step involves comprehending the core principles of Zero Trust and integrating them with your organization's existing security posture.

The transition to Zero Trust entails persistent continuous monitoring and authentication, alongside adaptive security strategies. Success also depends on implementing the appropriate technologies such as Identity and Access Management, robust encryption, network microsegmentation, cloud firewalls, and Secure Access Service Edge (SASE) solutions.

Future-Proofing Network Defense

ZTNA is revolutionizing network defense, compelling organizations to overhaul their security strategies. In an era where cyber threats are increasingly complex, the urgency for adopting a Zero Trust framework is crystal clear.

Embracing Zero Trust enables organizations to fortify their network defense, offering resilient protection against the ever-changing landscape of cyber threats. Although firewalls may require modifications to align with this innovative model, they remain integral to a comprehensive security strategy.

In the realm of VPNs, Timus steps in to address various drawbacks by ushering in ZTNA. Here's how Timus tackles the common VPN pitfalls:

  1. Streamlined Connectivity: Traditional VPNs often come with a clunky interface, making navigation a cumbersome task. Timus simplifies this by offering a smoother, more user-friendly experience.

  2. Persistent Connection: Unlike traditional VPNs that might require manual reconnection, Timus ensures a seamless, always-on connection, providing uninterrupted access to company resources.

  3. Enhanced Security: VPN credentials are susceptible to theft through social engineering and phishing attacks. Timus combats this vulnerability with advanced security measures, safeguarding against unauthorized access.

  4. Preventing Lateral Movement: With traditional VPNs, a hacker gaining access can potentially move laterally within the network using stolen credentials. Timus ZTNA implements strict access controls, minimizing the risk of lateral movement and fortifying network security.

Through Timus ZTNA, users enjoy secure, granular access to company resources, supported by a lightweight, OS-agnostic agent that ensures reliable connectivity. Say goodbye to VPN woes and embrace a more efficient and secure network access solution with Timus.


Traditional firewalls, based on perimeter-based security, fall short within ZTNA. These networks operate under the 'never trust, always verify' mantra, mandating continuous authentication and validation of all users and devices, which is beyond the capabilities of conventional firewalls.

Zero Trust is transforming cybersecurity by shifting from the outdated perimeter-based security approach to a user-centric model that demands continuous verification of every user and device seeking access to network resources.

In dynamic, user-centric networks, firewalls confront numerous obstacles, such as the inability to scrutinize encrypted traffic inline, prevent lateral movement of threats, and effectively manage security across hybrid cloud environments.

Cloud firewalls are particularly well-suited for Zero Trust architectures, as they integrate advanced features such as application awareness, intrusion prevention systems, and identity-based controls. These capabilities enhance the granular visibility and management of network traffic, making NGFWs a cornerstone in modern cybersecurity frameworks.

Zero Trust architecture is pivotal in future-proofing network defense, offering robust protection against the ever-evolving cyber threats. It achieves this through relentless authentication processes, adaptive strategies, and the deployment of cutting-edge technology, thereby fortifying the network's security posture. In conclusion, although the traditional role of firewalls is transforming within ZTNA, they remain indispensable. By adapting to the cybersecurity landscape, firewalls can maintain their critical role in cybersecurity. As the shift towards Zero Trust progresses, it's imperative for organizations to continuously refine their security strategies, ensuring readiness against the cybersecurity challenges that lie ahead.