Zero Trust is a modern security model, strategy, and framework that operates on the principle of “trust nothing by default.” This paradigm shift emphasizes that trust should not be assumed, and verification is paramount to maintaining security in today’s complex IT environments.
Key Principles of Zero Trust
- Never Trust, Always Verify
Trust is not implicit; it is considered a vulnerability. Every entity — a user, device, or request — is treated as a potential threat until verified.
This principle mandates continuous authentication and authorization processes to ensure security at every access point.
2. Assume Breach
Organizations should operate assuming that a breach has already occurred or will occur. This mindset encourages proactive security measures and rapid response strategies.
3. Verify Explicitly
All-access requests should undergo rigorous verification processes. This includes validating user identity, device security status, and context of the request.
4. Least Privileged Access
Instead of relying solely on role-based access control, the principle of least privileged access dictates that individuals are granted the minimum level of privileges necessary to perform their job functions effectively. This limits exposure to sensitive resources.
Fundamental Assumptions of Zero Trust
- Hostile Network Environment: The network is inherently considered hostile, and all entities must be verified.
- Persistent Threat Landscape: Both external and internal threats are continuously present and evolving.
- Insufficient Network Locality: Physical location or device origin cannot be trusted as a security measure.
- Dynamic Authentication and Authorization: Each device and user interaction is authenticated and authorized based on dynamic, context-aware policies rather than static configurations.
Zero Trust as a Security Model
Much like how ITIL provides a framework for IT service management and Agile offers methodologies for project management, Zero Trust serves as a foundational model for cybersecurity. Its implementation varies across organizations, reflecting different perspectives and needs.
Core Pillars of Zero Trust
- Users and Identity: Emphasizing strong identity verification and user management.
- Devices: Ensuring all devices accessing the network meet security standards.
- Network and Environments: Monitoring and securing network traffic and environments.
- Applications and Workloads: Protect applications and workloads through strict access controls.
- Data: Prioritizing data security and minimizing exposure to sensitive information.
The Necessity of Zero Trust
- Evolution of IT Infrastructure: As organizations adopt cloud services and hybrid environments, traditional security measures need to adapt.
- Introduction of DMZ (Demilitarized Zone): Utilizing DMZs for public-facing services enhances security by isolating sensitive resources.
- Increased Reliance on Cloud Services: With the growing adoption of cloud technologies, Zero Trust becomes critical in managing access and security across diverse platforms.
Zero Trust represents an evolution of traditional perimeter-based security approaches, which have proven inadequate in the face of modern IT infrastructure complexities. By redefining security parameters and focusing on granular policy enforcement, Zero Trust provides a more robust defence against emerging threats.
