Zero Trust Network Access (ZTNA) is a security architecture that enforces the principle of “never trust, always verify” by granting users access to specific applications or systems only after verifying identity, device posture, location, and context. Unlike traditional VPNs or network-centric models, ZTNA does not expose networks, instead, it provides application-layer access without establishing a full connection between the user and the internal network.
ZTNA is foundational to zero trust remote access, offering secure, policy-based connectivity across cloud, IT, and OT environments. It ensures that access is tightly controlled, limited to what is needed, and continuously validated.ZTNA addresses the growing risks of remote work, third-party access, and increasingly distributed infrastructures. Legacy technologies like VPNs grant broad network access, creating lateral movement opportunities for attackers if a device is compromised. In contrast, ZTNA minimizes the attack surface, prevents unauthorized access, and enforces least-privilege policies, regardless of the user’s location or network.
ZTNA is especially important for critical infrastructure (CI) and industrial control systems (ICS), where operational continuity and cyber-physical safety are paramount. In these environments, zero trust for ICS ensures that access to sensitive OT systems is not only restricted by role, but also by time, device trust, and real-time context.
By implementing zero trust access control, organizations can secure everything from zero trust remote desktops to vendor access under zero trust policies, while meeting stringent requirements in frameworks like IEC 62443, NERC CIP, NIS2, and TSA SD02E. ZTNA also supports zero trust connectivity strategies that decouple users from the network layer, enabling safer, more scalable access to industrial systems, cloud apps, and legacy assets alike.
Xona delivers ZTNA purpose-built for OT environments, combining zero trust principles with protocol isolation, credential injection, and session-level controls. Unlike general-purpose ZTNA solutions that were designed for cloud or IT-only use cases, Xona extends zero trust remote access into the most sensitive parts of critical infrastructure, without direct network exposure.
Users, whether internal engineers or third-party vendors, access operational systems through a browser-based interface, with all sessions proxied, audited, and governed via Xona’s hardened gateway. This enables zero trust remote login without requiring VPNs, jump servers, or endpoint agents. Every session is time-based, role-restricted, and observable in real time, delivering the zero trust access organizations need to secure ICS environments and meet compliance mandates.
For organizations looking to implement vendor access zero trust policies, Xona provides a controlled, scalable model that supports just-in-time access, session supervision, and moderated file transfers, ensuring that access is not only secure, but also operationally efficient.