Zero Trust Model

The Zero Trust Model is a cybersecurity approach based on the principle of "trust no one, verify everything." It shifts away from the traditional security model, which often relies on perimeter defense (like firewalls) to protect an organization’s internal network. Instead, the Zero Trust approach assumes that both internal and external networks are inherently untrustworthy, so every user, device, and application must be verified before gaining access to sensitive resources.

Here are the key concepts of the Zero Trust Model:

1. Trust No One, Verify Everything

• Core Idea: In a Zero Trust architecture, no user or device is trusted by default, regardless of whether they are inside or outside the network perimeter. Every request for access to any system, resource, or data must be authenticated, authorized, and continuously validated. Even if a device or user is already within the corporate network, it still needs to be verified before accessing any resource.

  This principle aims to minimize risks by assuming that attackers might already be inside the network (due to breaches or insider threats) and focuses on preventing unauthorized access even after someone has gained access to the network.

2. Least Privileged Access

• Core Idea: The least privilege principle is about granting the minimum level of access needed for users, devices, or applications to perform their tasks. Each user, device, or application is given just enough access to do their job, but no more.

  This limits the potential damage in case of a compromised account or system, because even if an attacker gains access to an account, they can only access the smallest possible set of resources needed for their attack, not the entire network.

  For example, if an employee in HR only needs access to HR-related data, they would be restricted from accessing finance or IT resources. Similarly, a device like a printer or an IoT device would only have access to what is necessary for its function, reducing its potential as a target for attackers.

Key Principles of Zero Trust

• Authentication and Authorization: All users, devices, and applications must be authenticated and authorized for each specific resource they are trying to access. Strong multi-factor authentication (MFA) is commonly used.

• Micro-Segmentation: The network is divided into smaller segments, and each segment is secured independently. This limits the "blast radius" in case of a breach, preventing attackers from moving laterally across the network.

• Continuous Monitoring: Even after access is granted, activities are constantly monitored and analyzed for unusual or malicious behavior. This ensures that access can be revoked or adjusted if any signs of compromise are detected.

• Data Encryption: Communication between devices and users is encrypted, ensuring data is protected both in transit and at rest.

In essence, Zero Trust replaces the old perimeter-based security approach, where the perimeter was assumed to be the main defense point, with a model where every access request, from inside or outside the organization, must be verified and monitored continuously. By following these principles, Zero Trust minimizes the attack surface, reduces the potential for lateral movement within the network, and provides better overall protection for sensitive data.