10.1 Understanding Zero Trust Network Access (ZTNA)

Zero Trust Network Access security is s a set of technologies and functionalities that enable secure access to internal applications, data, and services for remote users. Unlike VPNs, which grant access to entire networks, ZTNA allows access only to specific services or applications.

ZTNA's process involves multiple stages. Initially, it ensures the user's identity through an authentication process. Following successful authentication, it grants access to specific resources (applications, data, and services). This access is provided through a secure, encrypted tunnel, which acts as a protective barrier for the applications, concealing them from potentially harmful IP addresses. In this manner, ZTNA acts very much like software-defined perimeters (SDPs), relying on the same ‘dark cloud’ idea to prevent users from having visibility into any other applications and services they are not allowed to access. This also offers protection against lateral attacks, since even if an attacker gained access, they would not be able to scan to locate other services.

The Four Core Principles of ZTNA

Principle of Least Privilege Access (PoLP)

The principle of least privilege access is a cornerstone of cybersecurity strategies. It operates on the tenet that users should be granted the bare minimum access rights necessary to carry out their tasks. In other words, each user has just enough permissions to perform their role, but no more. This helps prevent unauthorized access to sensitive information and limits the potential damage from security breaches. If a user's account is compromised, the attacker will only have access to the privileges granted to that user, thereby containing the threat. Implementing least privilege access, therefore, becomes a proactive measure in minimizing the risk of internal and external threats.

Micro-Segmentation

The network is divided into isolated sections to prevent lateral movement of threats. This containment strategy minimizes the impact of security breaches and enhances overall protection.

Continuous Authentication

User identity and device health are continuously verified throughout the session. If suspicious activity is detected or the device health declines, access is revoked, ensuring real-time protection.

Policy-Based Access Control

Access is managed through dynamic policies that consider user roles, device attributes, and contextual factors. These policies adapt in real-time to changing conditions, ensuring appropriate access levels at all times.