Understanding Zero Trust Network Access (ZTNA)

Zero Trust Network Access (ZTNA) is a security model that controls and secures access to applications and IT resources based on the principle of "never trust, always verify." Unlike traditional approaches, ZTNA does not grant any access by default, even to internal users. Each request is systematically verified based on the identity, context, and security level of the device being used.

Adopted in the context of cloud computing, remote work, and increased cyber threats, ZTNA has emerged as a modern alternative to traditional VPN solutions and as a cornerstone of the Zero Trust model.

What is Zero Trust Network Access?

The ZTNA (Zero Trust Network Access) is a cybersecurity approach that focuses on securing access to applications rather than to the network as a whole. It relies on strict and continuous verification of each user and device before granting access to a specific resource.

Unlike traditional architectures based on a trusted perimeter, ZTNA is based on the premise that threats can originate from both inside and outside a network. Access is therefore granted on a granular basis, limited to a specific resource, and only if security requirements are met: identity, role, location, device status, etc.

The ZTNA This addresses the new security challenges associated with user mobility, the shift to cloud-based infrastructure, and the proliferation of SaaS applications, while improving visibility and access control.

How does ZTNA work?

ZTNA works by dynamically and contextually verifying each request for access to applications, without ever exposing the internal network. Access is granted only after a series of strict checks, performed both before and during the session.  
    1. User Identity Verification
      Each user must authenticate using strong authentication methods (identity, role, multi-factor authentication). ZTNA typically relies on an identity and access management (IAM) solution to verify that the user is authorized to access a given resource.


    2. Device Security Assessment Before granting access, ZTNA analyzes the status of the device being used: system updates, active antivirus, compliance level, and device type (work or personal device). A device deemed non-compliant may be denied access, even if the user is legitimate.

    3. Access is limited to the application, never to the network
      Unlike a traditional VPN, ZTNA does not grant blanket access to the network. Users can only access the specific application for which authorization has been granted, with no visibility into internal resources.

    4. Continuous verification during the session
      Trust status is never permanent. ZTNA continuously monitors the connection context (changes in location, behavior, or device status) and can revoke access in real time if a risk is detected.

Thanks to this approach, ZTNA makes it possible to drastically reduce the attack surface, mitigate risks, and effectively implement the principles of the Zero Trust model.

The Key Principles of ZTNA

ZTNA is based on a set of fundamental principles derived from the Zero Trust model, which redefine how access to digital resources is granted and controlled. These principles do not describe technical steps, but rather the security rules upon which any ZTNA architecture is based.
    1. Never trust by default
      ZTNA applies the fundamental principle of Zero Trust: no user, device, or connection is considered trustworthy by default, whether inside or outside the network. Every access request must be explicitly authorized.

    2. Access based on identity, not on the network
      In a ZTNA model, trust is no longer based on network location, but on the identity of the user and the device. This approach eliminates the need for a traditional network perimeter and secures access in hybrid and cloud environments.

    3. Principle of Least Privilege
      ZTNA strictly enforces the principle of least privilege: a user is granted access only to the resources strictly necessary for their role. No global or broad access is granted, which significantly limits risks in the event of a compromise.

    4. Granular, application-based access
      Unlike traditional approaches, ZTNA relies on application-by-application access rather than broad network access. This principle reduces the attack surface and prevents visibility into other internal resources.

    5. Continuous verification of trust levels
      Trust is never permanent. ZTNA relies on continuous assessment of the security context, allowing access rights to be adjusted or revoked if the risk level changes.

    6. Reducing the attack surface
      A key principle of ZTNA is to make applications invisible to unauthorized users. Resources are accessible only after explicit authorization, which significantly limits attacks based on reconnaissance or network scanning.

ZTNA vs. VPN: What Are the Differences?

ZTNA (Zero Trust Network Access) and VPN (Virtual Private Network) share the common goal of securing remote access to corporate resources. However, their approaches to security, access management, and network exposure are fundamentally different.

A VPN is based on a trusted perimeter model: once connected, the user has broad access to the internal network. If an account or device is compromised, an attacker can exploit this visibility to move laterally within the information system. Outdated VPNs also present an opportunity for cyberattackers.ZTNA, on the other hand, applies the Zero Trust principle by granting strictly limited access to authorized applications, without ever exposing the underlying network.

In short, ZTNA eliminates this risk by:
  • never granting access to the network
  • limiting rights to a specific application
  • by continuously monitoring the security context

This approach significantly reduces the attack surface, while better suited to modern environments that combine cloud, SaaS, and remote work.


ZTNA is therefore more suitable:
  • for cloud and hybrid environments
  • for organizations adopting a Zero Trust strategy
  • for companies seeking to secure remote work in the long term

What are the benefits of ZTNA?

  1. Restrict access to enhance security
    ZTNA restricts access to only the necessary resources, linking them to specific users and contexts. This approach reduces the risk of intrusion and prevents the spread of threats through strict, continuous verification.

  2. Secures hybrid and remote environments
    ZTNA is designed for hybrid and remote environments, where users access resources from different locations and devices. It effectively secures access to cloud and SaaS applications, including in remote work and BYOD scenarios.

  3. Significantly reduces the attack surface
    By limiting resource visibility to authorized users only, ZTNA prevents attackers from mapping the information system. This reduction in exposure significantly shrinks the attack surface and lowers the risk of vulnerabilities being exploited.

  4. Facilitates regulatory compliance
    ZTNA enables centralized management of identities and security policies, providing greater visibility into access. Through audit logs and granular controls, it helps organizations meet the requirements of regulations such as GDPR and PCI-DSS.

  5. Enhances the user experience
    ZTNA provides secure and seamless access to applications without relying on complex VPNs. It boosts user productivity through fast connections and features such as Single Sign-On (SSO) and adaptive authentication.
Ekinops U-ZTNA provides an additional layer of protection by granting access only to the applications users need for their work, regardless of their location (office, on the go, working remotely, etc.).