What Is Zero Trust Network Access (ZTNA)?

Zero Trust Network Access (ZTNA) is important because it aligns with the growing need for adaptable, resilient cybersecurity in an increasingly distributed, digital-first workplace.

Here’s why it has become a critical framework:

Protection against evolving threats. Traditional security models, which grant broad network access to internal users, are insufficient against today’s sophisticated cyberthreats, especially insider threats or threats arising from compromised credentials. ZTNA assumes that no entity is inherently trusted, limiting potential attack vectors.

Support for remote work and cloud-based resources. With the rise of remote work and cloud adoption, businesses are shifting away from traditional on-premises networks to hybrid or fully cloud-based infrastructures. ZTNA provides secure access to resources from any location, enforcing security policies consistently across on-premises and cloud environments.

Mitigation of lateral movement in cyberattacks. In a security breach scenario, ZTNA’s segmented access prevents lateral movement by attackers, limiting the scope of potential damage. Since access is granted only on a need-to-know basis, attackers find it much more difficult to move between systems and gain access to critical assets.

ZTNA provides numerous benefits for businesses including:

Enhanced security. ZTNA’s model of continuous identity and device verification reduces the risk of unauthorized access and mitigates threats from compromised credentials. By verifying each access attempt based on factors like identity, location, and device health, ZTNA strengthens overall security posture and minimizes unauthorized access.

Improved access control and policy enforcement. ZTNA allows organizations to enforce granular, role-based access policies. Users are granted access only to the applications or resources they need, reducing the chances of accidental or intentional access to sensitive data. It also simplifies compliance with data protection and privacy regulations by ensuring that access is limited and logged.

Reduced attack surface. Since ZTNA doesn’t expose the entire network to any single user or device, it reduces the attack surface significantly. Only authorized users and devices can access specific resources, and they can only access them via secure, encrypted connections, lowering the risk of a data breach or unauthorized exposure.

Traditional security models primarily rely on the concept of a "trusted" internal network and an "untrusted" external network, secured by firewalls and VPNs. Key differences between Zero Trust Network Access (ZTNA) and these traditional models include:

Perimeter-based versus identity-based. Traditional security relies on securing the network perimeter, assuming users within the network are trusted. ZTNA treats every access attempt as potentially risky, regardless of location, requiring identity verification each time.

Implicit versus explicit trust. In traditional models, once authenticated, users are trusted and often move laterally within the network with little restriction. ZTNA, however, implements micro-segmentation and least-privilege access to limit lateral movement and reduce risks associated with compromised credentials.

Static versus dynamic access control. Legacy security models typically have static rules, which are less flexible and often outdated in today’s environments. ZTNA uses dynamic policies that adapt based on risk factors, user behavior, and other contextual cues.

VPN versus direct, secure access. Traditional network connectivity models often use VPNs for remote access, which can introduce latency and are challenging to scale. ZTNA solutions provide secure access directly to applications without routing all traffic through a VPN, improving performance and scalability.

Zero Trust Network Access (ZTNA) is part of the Security Service Edge framework and is used to secure access to private resources built on Zero Trust principles. In a ZTNA environment, users, devices, and applications must continuously prove their legitimacy before accessing resources, regardless of their location within or outside the network. Key operational mechanics include:

Identity and access management. ZTNA starts with strict identity verification. Each user or device must authenticate their identity, often through multi-factor authentication (MFA), before gaining access to any application or resource. This ensures only legitimate users are identified and granted access.

Micro-segmentation. Instead of relying on a single network perimeter, ZTNA divides the network into smaller, isolated segments. Each segment contains specific resources or applications, making it difficult for attackers to move laterally within the network if they compromise one segment.

Least privilege access. Each user and device is granted access only to the specific applications or data necessary for their roles, limiting potential exposure. This least privilege approach minimizes the risk of data breaches or unauthorized access by limiting what any one compromised account can access.

Application-level access. Rather than granting broad network-level access, ZTNA supports application-specific connections. This means that even if a device is granted access, it only communicates with the specific application or resource it’s authorized to access. It further reduces the attack surface, as users and devices don’t have visibility or access to the entire network.

Continuous access evaluation. Continuous evaluation of user and device behavior is a central component of ZTNA. This includes monitoring for any unusual activity patterns, device posture (such as whether security updates are installed), and changes in location. When anomalies are detected, access may be revoked or additional authentication required.

Zero Trust Network continues to evolve to address the growing complexities of modern cyberthreats and remote work environments. Initially, ZTNA introduced the core principles of Zero Trust by providing access based on user identity and device posture rather than traditional network perimeter defenses. However, as cyberthreats have evolved, so has the need for a more comprehensive and adaptive approach, leading to the development of advancements in ZTNA including:

Granular application access control. ZTNA now provides more detailed access control at the application level, moving beyond simple network or IP-based access. It ensures that users have access only to the specific applications and resources they need, and within those applications, limits them to the specific data and operations they’re authorized to perform.

Continuous trust assessment. Traditional ZTNA generally relied on a one-time trust assessment at the start of a session. ZTNA now adopts a continuous trust model, evaluating user and device behavior dynamically throughout the session. Continuous monitoring helps detect and respond to anomalies or risky behavior in real-time.

Integrated threat prevention. ZTNA now integrates threat prevention capabilities, such as malware detection, intrusion prevention, and other security checks, directly into the access model. This proactive security layer helps prevent attackers from moving laterally within a network even if they gain initial access.

Enhanced user and device context awareness. ZTNA now goes beyond just verifying user identity and device posture, incorporating more contextual factors such as user behavior patterns, device history, and environmental factors like geolocation and time of access. This helps create a more precise risk profile for each access request.

Secure access service edge (SASE) is a cybersecurity framework that combines networking and security services in a unified, cloud-native model. It aims to provide secure access to users regardless of their location by integrating security functions—like secure web gateways, cloud access security brokers, firewall-as-a-service, and Zero Trust Network Access—with wide-area networking capabilities. SASE offers a scalable, flexible way to secure a distributed workforce, especially useful in modern environments where remote work and multi-cloud environments are standard.

ZTNA is a key component within the SASE model, focused specifically on access control based on Zero Trust architecture. While ZTNA enforces strict access controls at the application and resource level, SASE broadens this scope by providing a comprehensive security and networking model. In essence, ZTNA is a critical element of SASE, focusing on fine-grained access management, while SASE incorporates ZTNA within a larger set of security tools to provide unified, end-to-end protection across the entire network.

Microsoft Zero Trust Network Access (ZTNA) solutions are designed to provide secure access to applications and resources, regardless of where users are located.


The core component of this approach is Microsoft Entra Private Access, which replaces traditional VPNs. It helps secure access to all private apps and resources for users anywhere with an identity-centric ZTNA solution. Microsoft Entra Private Access allows you to replace your legacy VPN with ZTNA. Without making any changes to your apps, you can extend Conditional Access policies to your network using identity-centric access controls and enable single sign-on (SSO) and multifactor authentication (MFA) across all private apps and resources. Through Microsoft’s global private network, employees get a fast, seamless access experience that balances security with productivity.