In recent years, the way we work has undergone significant changes. Companies have adopted hybrid and distributed models, with employees, collaborators, and partners connecting from various locations, whether from home or on the move. The number of devices in use—sometimes personal ones—has increased, along with the number of attack surfaces and threats, which now affect organizations of all sizes.
So how can we proactively protect remote access to corporate data and applications while maintaining the right balance between security and productivity? The answer is called Zero Trust Network Access (ZTNA).
What is Zero Trust Network Access Architecture
The Zero Trust model is rewriting the rules of IT security. Recent research by Research and Markets estimates that the ZTNA solutions market will grow at a compound annual growth rate of 20.4% through 2030. This figure is not surprising, given the growing need to secure access to corporate resources in the era of distributed work.
To better understand ZTNA, it is useful to start with the concept of Zero Trust. The National Institute of Standards and Technology (NIST) defines it as “a cybersecurity paradigm focused on the principle that trust is never implicit and must be continuously evaluated.” In other words, trust is not granted by default: it must be earned and maintained.
Zero Trust Network Access (ZTNA) applies this paradigm to network and resource access, whether on-premises, in the cloud, or in a hybrid model. Instead of giving a user unrestricted access to a network after entering a simple ID and password, ZTNA takes a more granular approach: access is granted only to the specific applications or resources required, and only after a dynamic and thorough authentication and authorization process.
Why a VPN is No Longer Enough
For decades, the standard solution for remote access has been the VPN (Virtual Private Network)—a simple, direct, and functional approach when IT resources were concentrated in data centers and corporate networks.
Today, the scenario is very different: applications are not only on-premises but distributed across cloud and SaaS environments. Users connect from multiple devices, and, crucially, cybercriminals have refined their techniques, exploiting any access point to move laterally within networks, expand their reach, and compromise critical data and applications. In this context, VPNs have structural limitations:
- They provide access to an entire network rather than specific resources.
- They do not distinguish risk levels associated with users or devices.
- They lack native dynamic control mechanisms.
Zero Trust Network Access: How It Works in Practice
Adopting a Zero Trust Network Access paradigm means granting access to networks, applications, and data only after granularly verifying user identity, device trustworthiness, permissions, and connection context.
To better understand the process, imagine a user accessing a corporate application remotely from a personal smartphone (BYOD), such as a SaaS platform for the sales team.
Access Request
The user opens the application on their smartphone. The request is intercepted by a ZTNA broker/controller, which collects relevant information from the user’s device and manages the entire validation process.
Device, Identity, and Context Verification
The ZTNA broker processes the request through two main checks: device verification and user authentication.
- Device trust: The broker assesses the connecting device. It verifies whether it is authorized, whether it belongs to the company or is a BYOD, whether the operating system is up to date, and whether antivirus and endpoint protection are active.
- User identity: The user’s identity is usually verified via multi-factor authentication (MFA), integrated with corporate directories (e.g., Active Directory, Azure AD). Only a favorable combination of a trusted device and an authenticated user increases the trust level, allowing the process to continue.
In addition, the connection context is carefully evaluated: the user’s location, time of access, network used, and any anomalous behaviors. This behavioral analysis often employs machine learning techniques to assign a risk score to each access attempt and decide in real time whether to allow it, request further verification, or block it entirely.
Policy Application and Role-Based Control
Once authentication is complete, corporate policies — usually based on the role-based access control (RBAC) model — are applied. The user can access only the applications and functionalities permitted for their role.
Secure and Granular Connection
The broker establishes an end-to-end encrypted connection between the user and the authorized application. The internal network remains hidden, and other resources are inaccessible—access is targeted, limited, and invisible to unauthorized users.
Continuous Posture Check
Once access to the “minimum necessary” resources is granted, the system continuously monitors security posture, especially behavioral parameters. For instance, if anomalous behaviors are detected, such as massive file downloads or simultaneous access attempts from incompatible locations, access privileges are immediately revoked.
ZTNA Architecture Components
Implementing a ZTNA architecture requires several components to work synergistically:
- The system core is the ZTNA Controller/Broker, which orchestrates the entire access process, evaluates policies, authenticates users through the Identity Provider, analyzes behavior, and verifies device security. It does not handle application data traffic directly but instructs the gateway to do so.
- ZTNA Gateway: Positioned in front of the protected application, it enforces the controller’s decisions, manages network traffic, establishes secure tunnels, and blocks unauthorized attempts.
- Identity Provider: Part of Identity and Access Management (IAM) solutions, it verifies user identity, integrates with corporate directories for authentication, and enables advanced security measures like MFA.
- Policy Engine: Contains rules and policies defining who can access which resources, from where, and under what conditions. Policies are dynamic and based on attributes such as user identity, device state, location, and time.
Why It’s Time to Make the Change
Adopting ZTNA involves a modernization journey more complex than traditional approaches, but it is far more robust, reliable, and aligned with today’s business environment. With the right partner, companies can overcome initial challenges and gain tangible benefits.
Preventive Security
Every access is verified and monitored, drastically reducing the risk of compromise and lateral movement.
Reduced Attack Surface
Access is limited to authorized applications only, without exposing the entire internal network.
Enhanced Productivity
Users reach the resources they need directly, without complex tunnels and with minimal impact on application performance.
Work Modernization
The model adapts easily to hybrid work scenarios, improving workforce productivity and helping attract and retain top talent.
Our Commitment to Preventive Security
At Kirey, we see security as an enabler of business growth. We provide clients with a comprehensive ecosystem of expertise to protect their organizations and guide them toward modern, productive work models. In other words, we handle both infrastructure and application modernization and the management of inevitable associated risks. Adopting a ZTNA paradigm is one of the measures we implement to achieve this goal.
To learn more and explore how to embark on a journey toward security in the cloud era, contact us: our experts are ready to assist.
