What is a Zero Trust Architecture

4 min. read

Zero Trust Architecture, or ZTA, refers to the implementation, practical application and design that enforces Zero Trust principles in an organization’s IT infrastructure. It provides the technical framework and structure organizations use to enforce Zero Trust. ZTA includes various security technologies, such as:

  • Identity and Access Management (IAM)
  • Multi-factor Authentication (MFA)
  • Micro-segmentation
  • Encryption
  • Real time Monitoring.

ZTA outlines how these principles are applied across an enterprise's systems, networks, and workflows to ensure that no entity (user, device, or application) gains access without thorough validation.

Simplifying Zero Trust for User-Based Security

Understanding Zero Trust Architecture

Introduced in 2011 by John Kindervag, a former analyst at Forrester Research, Zero Trust architecture has never been more critical. Digital transformation continues to accelerate, bringing a close to the era of on-premises systems and software and ushering in multi-cloud environments, an exploding Internet of Things (IoT) ecosystem, and enhanced mobility.

Additionally, users demand direct access to resources from anywhere to collaborate and stay productive. Zero Trust architecture makes this shift possible without compromising security.

What Are the Key Elements in a Zero Trust Architecture?

The core principles of Zero Trust are typically associated with securing users or use cases like Zero Trust network access (ZTNA). However, a comprehensive Zero Trust architecture encompasses users, applications, and infrastructure and materially enhances an organization's security posture.

  • Users—Strong authentication of user identity, application of the principle of least privilege access, and verification of user device integrity are foundational parts of Zero Trust architecture.
  • Applications—A fundamental concept of Zero Trust architecture is that applications cannot be trusted, and continuous monitoring at runtime is necessary to validate their behavior. Applying Zero Trust to applications removes implicit trust between various application components when they talk to each other.
  • Infrastructure—Zero Trust architecture addresses all security related to infrastructure (e.g., routers, switches, cloud, IoT, and supply chain).

What Are the Three Principles of Zero Trust?

The Zero Trust architecture is based on three foundational principles: verification, least privilege access, and assumption of breach.

Continuously Monitor and Validate

Resource usage should be continuously monitored to detect unusual behavior. Organizations should verify users' authenticity by authenticating and authorizing them based on all available data points, including location, user identity, service or workload, and data classification. Multifactor authentication, device health checks, and application whitelisting are recommended for verifying a user's identity, device posture, and application integrity.

Enforce Least Privileged Access

The principle of least privilege restricts users’ access rights to only the data, applications, and services they need to perform their authorized functions. This Zero Trust architecture principle is enforced using granular access controls, just-in-time (JIT), and just-enough access (JEA).

Risk-based, adaptive access policies also help balance security and productivity. Following the principle of least privilege helps minimize potential exposure or damage from insider threats or compromised user accounts.

Assume Breach

Zero Trust architecture is based on the assumption that security breaches are inevitable and the threats that cause them can be inside and outside an organization’s network perimeter. A key objective of Zero Trust architecture is to minimize the blast radius of a breach when it occurs.

This entails micro-segmenting sensitive resources, using end-to-end encryption, continuously monitoring user and device behavior for anomalies, and implementing robust incident response and recovery mechanisms.

The Benefits of ZTA

ZTA creates a more secure and adaptable environment for modern businesses, reducing the risk of attacks and ensuring comprehensive protection across diverse and complex IT infrastructures. ZTA offers several key benefits to organizations, especially in the face of evolving cybersecurity threats. These include:

Enhanced Security

Reduces attack surfaces by enforcing least-privilege access, meaning users and devices only access what they absolutely need. Continuous authentication and authorization prevent unauthorized users from accessing sensitive data or systems, reducing the risk of insider and outsider threats.

Protection Against Data Breaches

By requiring authentication for every request, ZTA minimizes the risk of data breaches, even if a user or device within the network is compromised. The assumption of "breach" ensures no implicit trust is given, limiting attackers' lateral movement.

Improved Visibility and Monitoring

ZTA relies on continuous monitoring and logging, which enhances an organization’s visibility over network activities. This helps detect and respond to threats more effectively and allows for better audit trails.

Reduced Risk of Advanced Persistent Threats (APTs)

By isolating network segments and verifying access at each level, ZTA minimizes the impact of advanced persistent threats, which often rely on moving undetected within a network.

Scalability

Zero Trust Architecture can easily scale to accommodate an organization's growing number of users, devices, and applications, making it suitable for small and large businesses.

Improved Incident Response:

ZTA provides more granular control over the network, allowing security teams to quickly identify and isolate compromised resources and reduce the time it takes to respond to incidents.

Support for Remote Work and Cloud Environments

Adopting a Zero Trust architecture allows organizations to securely support distributed workforces and partners operating in multicloud environments. With Zero Trust architecture, users have access to the systems and data they need without putting these valuable resources at risk of cyber attack.

Addresses Compliance Requirements

Zero Trust architecture aligns seamlessly with regulatory data protection requirements such as GDPR, HIPAA, and PCI-DSS. It provides enhanced security by minimizing the attack surface, requiring multifactor authentication, and enforcing strict access controls.

Reduces Insider Threats

By enforcing strict access controls, Zero Trust architecture significantly reduces the instances of and potential damage from insider threats. Restricting access to only the minimum needed to perform authorized functions prevents lateral movement across networks that expose resources to malicious activity.

Extends Security Beyond Isolated Network Locations

Zero Trust architecture employs software-defined perimeters and microsegmentation to support strict access controls, allowing authorized movement across networks. Users' privileges follow them across multiple locations and are continuously validated.

What Are the Five Pillars of Zero Trust?

The US Cybersecurity and Infrastructure Security Agency (CISA) developed the five pillars of Zero Trust to help organizations address increasing cyber threats while transitioning to a zero trust architecture. Understanding these pillars is critical for effectively using ZTA.

#1: Identity

Identity refers to the attributes that describe both human and non-human users. Within a Zero Trust architecture, controls are essential to manage each user’s access requests, ensuring that the appropriate access is granted without excessive rights.

Some recommended identity access controls include single sign-on (SSO) solutions, multifactor authentication (MFA), and identity and access management.

#2: Devices

A device refers to any asset that can connect to a network (e.g., servers, desktops and laptops, printers, mobile devices, IoT devices, and networking equipment), including bring-your-own-device (BYOD) assets.

To prevent unauthorized access, organizations should maintain an inventory of all assets, including their configurations and associated vulnerabilities. Additionally, all devices should comply with the core principles of Zero Trust architecture.

#3: Networks

A network refers to any open communications channel, such as an organization’s internal networks, wireless networks, and the Internet. Zero Trust architecture provides protection for modern environments with porous perimeters.

Several approaches associated with Zero Trust architecture include encrypting network traffic, moving from traditional network segmentation to microsegmentation, and monitoring user and entity behaviors to proactively identify and respond to security issues, such as a data breach.

#4: Applications and Workloads

Applications and workloads include all systems, computer programs, and services that execute on-premises, on mobile devices, and in cloud environments. Zero Trust architecture directs continuous monitoring and validation of these tools to ensure secure deployment and service delivery.

This means moving from one-time, static access with implicit trust to dynamic authorization for continued access and proactive detection of unusual behavior by human and non-human users.

#5: Data

Data encompasses all information, from structured and unstructured files to fragments and metadata, stored across an organization’s digital infrastructure, including applications, systems, devices, networks, databases, and backups. With a Zero Trust architecture, all data must be protected from unauthorized access and exfiltration, whether it is in motion, in use, or at rest.

What Are the Seven Core Pillars of Zero Trust Architecture?

The 7 Core Pillars of Zero Trust Architecture are derived from more detailed frameworks like the Department of Defense (DoD) Zero Trust Reference Architecture, adding two additional focus areas. These seven pillars include the five above and emphasize two critical elements: automation and security operations.

#6: Visibility and Analytics

A comprehensive monitoring system actively tracks all user activities, device interactions, network traffic, and other relevant data to identify any anomalies and suspicious behaviors. This data is continuously analyzed to swiftly detect and respond to any potential threats, ensuring the safety and security of our system.

#7: Automation and Orchestration

ZTA leverages automated systems to implement and uphold security protocols, as well as to promptly address potential security risks in real time. This approach enhances the efficiency and precision of the response to potential security incidents.

How to Implement Zero Trust Architecture

Implementing Zero Trust Architecture (ZTA) requires a structured approach that redefines how security is enforced across the organization. It involves adopting new technologies, processes, and mindsets to ensure that no user, device, or system is trusted by default. Here is a step-by-step guide to implementing Zero Trust Architecture:

Identify Assets

A comprehensive inventory of all assets, including on-premise and cloud systems, should be created. Each asset should be evaluated to determine its value and vulnerability.

Verify Devices and Users

All devices and users must be validated to confirm that they are who or what they say they are. This verification can be supported through multi-factor authentication for users, embedded chips in devices, and behavior analytics for IoT devices.

Map Workflows

Mapping workflows is critical for Zero Trust architecture. This step involves defining who accesses which assets, when they can access them, and why access should be granted.

Define and Automate Policies

Authentication policies should be defined based on users' and workflows' characteristics. This should consider metadata such as device, location, origin, and time of requested access, as well as contextual data such as recent activity and multi-factor authentication (MFA). Firewalls can be used to automate the screening process for these attributes.

Test, Monitor, and Maintain

Before deployment, Zero Trust architectures should be tested to ensure that threats are effectively addressed and the impact on users’ productivity is minimal. Security teams should monitor users’ behavior continuously to detect anomalies that indicate a security breach. Additionally, all systems should be updated regularly to optimize security and performance.

Examples of Zero Trust Architecture

Using a Zero Trust architecture is highly recommended for any organization that relies on a network and stores digital data. The following use cases explain why ZTA has become a security best practice:

  • Protects data, applications, and networks
  • Secures remote access to on-premises and cloud applications and resources
  • Detects insider threats and mitigate potential damage
  • Replaces or augment a VPN to extend secure access control to connections from anywhere
  • Controls or block the use of unsanctioned apps (i.e., shadow IT)
  • Extends restricted, least-privilege access to external parties (e.g., partners and customers)
  • Gains access control over container and cloud environment
  • IoT visibility

Zero Trust Architecture FAQs

A Zero Trust architecture (ZTA) is a security model for implementing Zero Trust principles. In contrast, Zero Trust network access is a way of deploying Zero Trust architecture to restrict asset access in accordance with the principle of least privilege.
Organizations can address potential user resistance by ensuring ongoing communication and training to help users understand the importance of stricter access controls and additional security measures.
Integrating Zero Trust solutions with existing systems and cybersecurity tools can be complex due to the need for careful planning and execution. It often requires significant changes to infrastructure and processes.
Tools used as part of Zero Trust architecture include identity and access management (IAM), multifactor authentication (MFA), next-generation firewalls (NGFWs), endpoint detection and response, cloud access security broker (CASB), and Secure Access Service Edge (SASE).
Yes, in 2020, NIST published Zero Trust Architecture (NIST SP 800-207) which defined the basic tenets and deployment models of ZTA. To address Zero Trust architecture for the cloud, it published Zero Trust Architecture Model for Access Control in Cloud-Native Applications in Multi-Cloud Environments (NIST SP 800-207A) in 2023.