How to Implement Zero Trust

implementing zero trust

Zero trust security models are replacing outdated perimeter approaches to provide resilient access management in a world of remote work and hybrid cloud networks.

Zero trust minimizes the risk of data breaches by validating user identity with every access request.

Rather than assuming requests are safe just because of where they are made (i.e., from inside the corporate network), zero trust adds the layers required to continually authenticate users and devices.

But, zero trust implementation presents many challenges.

(there is no out-of-the-box solution.)

You have to overhaul your existing security policies and implement a new strategy based on the 3 core principles of zero trust.

The Core Principles of Zero Trust

The zero trust approach to security requires trust to be continually earned, not granted by default based on network location. It shifts the focus away from perimeter security models, where security controls are enforced at the network perimeter and everything inside is assumed to be safe.

Instead, it requires continual verification using strict authentication and authorization processes regardless of location.

Zero trust can be defined by three core principles:

#1. Never Trust, Always Verify

No entities (users, devices, applications, etc.) are assumed to be trustworthy. They must verify their identity using multiple factors with each access request. Robust security strategies never assume someone is who they say they are just because they have gained access to your corporate network. 

Given the rise of attacks targeting credentials, including infostealer attacks that increased by 58% in 2024, it is easier than ever for attackers to gain unauthorized access to networks. By never trusting entities on your network and always verifying their identity, you can prevent lateral movement after a breach.

This limits the impact of an attack as they are unable to compromise more systems.

#2. Principle of Least Privilege

The principle of least privilege states that network entities should only be given access to the data and resources they need to perform their role, i.e., the least amount of access or privilege without impacting their work.

Least privilege limits the impact of data breaches involving compromised accounts or insider threats.

Assume Breach

Given the current threat landscape, zero trust assumes that security breaches are inevitable. By assuming breaches have and will occur, zero trust works to implement security controls that minimize their impact.

This includes a range of potential strategies, such as:

Implementing Zero Trust: The Right Way to Do It

Overcoming the challenges of implementing zero trust and learning how to do it the right way requires a clear and well-thought-out plan.

Listed below are 7 steps detailing how to implement zero trust in 2025. By following these processes and adapting zero trust implementation to meet your network requirements, you can increase your chances of success and maximize future protection.

#1. Assess Your Current Security Posture

The first step to implementing zero trust is assessing your current security posture. This requires a full audit of the existing IT infrastructure, including:

  • Network users
  • Their roles
  • The applications and services they use to complete their work effectively
  • The devices they use
  • Existing access levels and user identity procedures

This is a significant undertaking and one of the biggest challenges of implementing zero trust. However, there are tools that can make the process easier, including:

  • Asset discovery platforms
  • Vulnerability scanners

After auditing your IT infrastructure, you should be able to define your attack surface and develop a clearer plan for your zero trust implementation. Plus, you can spot existing risks that can be quickly fixed for simple and immediate security posture improvements.

This first step provides the data needed to effectively implement a zero trust framework across your organization and identify where best to invest your time and resources.

#2. Define Your Protected Surface

While performing a full audit and establishing your entire attack surface is a great starting point, it helps to prioritize the most important and vulnerable data and resources first. Implementing zero trust across an organization’s entire IT infrastructure is complex, particularly for larger operations.

Therefore, breaking it down into multiple phases is a more straightforward approach, and starting with the most vulnerable network assets is logical. Your most valuable data and resources that require the most protection are sometimes referred to as the “protected surface.”

This is a smaller subsection of your full attack surface. Areas it should include could be:  

  • Sensitive Data: Including customer and employee information, proprietary business data, or intellectual property. To help identify your most sensitive data, consider what is protected by regulations and what would cause the most damage if it fell into a third party’s hands.
  • Critical Applications: These are the applications that handle your sensitive data and are vital to running your business. Narrow this down to only the most critical business processes.

Defining a protected surface prevents you from becoming overwhelmed at the start of your zero trust implementation. It enables you to perform a phased rollout that focuses on the most critical areas first or to apply your resources where they can provide the best protection. 

You can’t protect everything equally.

You will have to prioritize and choose a targeted approach to optimize resource allocation while also reducing the complexity of the task.

#3. Map Transaction Flows

If defining your protected surface shows you what to focus on, mapping the transaction flows shows you how data and users interact with it. You want to discover how your network operates and the dependencies associated with each system.

For example:

  • Who accesses what parts of the network?
  • What is the context by which they do this?
  • What time of the day do they typically access different systems?
  • Where are they accessing them from, and what device are they using?

To help achieve this, you will need access logs, application telemetry data, and network diagrams that map out how each asset fits into the bigger picture and the systems they communicate with.

By mapping out transaction flows, you can tailor future zero trust policies and reduce disruptions during implementation. It can also help future network updates by identifying potential improvements, like redundancies or unnecessary high-risk connections that require additional security controls.

#4. Architect a Secure Network

Based on zero trust principles, architect a secure network designed specifically for your protected surface and transaction flows.

This should include segmentation that breaks up the network into smaller, more isolated sections.

Traditional flat networks allow attackers to move freely. Zero trust architectures, such as micro-segmentation, prevent this lateral movement by isolating systems and requiring additional verification at each step. Beyond limiting the impact of a breach, segmentation also provides better visibility into network traffic and user behavior.

Monitoring network traffic for suspicious behavior is vital to identifying potential threats.

#5. Develop Access Policies

Create access policies that are context-aware and dynamic while enforcing the principle of least privilege to ensure maximum protection.

Static policies can quickly become outdated or over-permissive, leading to abuse by attackers. Adaptive policies that take into account contextual data (identity, device, location, time, behavioral patterns, etc.) are more resilient and better respond to the real-world needs of your employees.

While developing access policies is vital, the security they provide is only as strong as the authentication procedures that enforce them.

During zero trust implementation, consider whether your existing authentication mechanisms are strong enough or if you require more advanced procedures such as multi-factor authentication, security tokens, or biometrics to verify user identity.

#6. Leverage Zero Trust Technologies

A range of security technologies can help you implement zero trust policies.

These tools provide the mechanisms required to consistently enforce the principles discussed above across each layer of your infrastructure. 

Technologies to consider during zero trust implementation include:

  • Identity & Access Management (IAM): Centralize access policies to deliver consistent and secure operations across different services. These tools also enable adaptive access policies to improve security while minimizing impact on user experience.
  • Endpoint Detection & Response (EDR): Tools that monitor device health and isolate compromised endpoints before they enable data breaches.
  • Cloud Access Security Broker (CASB): Provide visibility to understand how users interact with SaaS applications and gain insights to better design and enforce zero trust security practices.
  • Secure Access Service Edge (SASE): Combines networking and security to enforce policies, including zero trust, across all users and devices regardless of location.

#7. Address Common Challenges

Zero trust implementation is also not a one-off project, but rather an ongoing transformation. While the steps above help improve the success rate, there will be challenges remaining that require consistent maintenance.

The most common challenges of implementing zero trust include:

  • Dealing with legacy systems
  • Educating staff on the benefits of new zero trust workflows
  • Implementation within budgetary or resource constraints
  • Integrating consistent zero trust policies across complex networks

To help overcome these challenges, take a phased approach starting with your protected surface defined in step 2. Also, invest in employee training to reduce organizational resistance.

Maximize Security with Check Point’s SASE

While there isn’t a single point product that can implement zero trust on its own, there are solutions that make its implementation significantly easier.

SASE in particular allows organizations to combine network and security capabilities into a single framework to deliver consistent protection regardless of location. This includes continuous verification across the network based on zero trust principles.To learn more about Check Point’s SASE solution, get in touch with our sales team today.

FAQs

What is the Zero Trust Security model? 
It’s an approach that treats every user, device, and application as a potential threat, requiring continuous verification and access controls, regardless of their location or affiliation.
Why is Zero Trust important for modern cybersecurity?
These days, cybersecurity requires Zero Trust because traditional perimeter-based security models are no longer sufficient in distributed and cloud-centric environments where threats can originate from both inside and outside.
What are the benefits of Zero Trust Security?
It offers several benefits, including reduced risk of data breaches and lateral movement of threats, improved visibility and control over access, and more proactive and resilient security measures.
How do you implement Zero Trust Security?
Assess your security posture and establish strong identity and access management. Prioritize micro-segmentation and granular perimeters, security analytics, and continuous monitoring. Finally, enforce least privileged access controls.
What are the key principles of Zero Trust Security?
Zero trust bases itself on four key principles: never trust by default, always verify, assume breach, and enforce least privileged access (users only have the minimum required access).

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