Zero trust is a security model built on the rule “never trust, always verify.” No user, device or app is trusted by default just because it sits inside your network. Every access request is checked using identity, device health and context, granted with least privilege, and monitored continuously on the assumption that a breach can happen. Zero trust is a strategy, not a single product you can buy.
What is zero trust security?
Traditional security worked like a castle and moat: strong defenses at the network edge, and broad trust for anyone inside. That fails when staff work remotely, apps live in the cloud and attackers steal valid passwords. Zero trust drops the idea of a trusted inside. The model was popularized by Forrester analyst John Kindervag around 2010 and formalized in NIST SP 800-207, the Zero Trust Architecture standard published in 2020. Google’s BeyondCorp program is an often-cited early example of the approach at scale.
The core principles of zero trust
- Verify explicitly. Authenticate and authorize every request using all available signals, such as identity, device health, location and behavior.
- Use least privilege. Give people and systems only the access they need, for only as long as they need it.
- Assume breach. Design as if an attacker is already inside, so you limit the damage and detect problems quickly.
The five pillars of zero trust
The US Cybersecurity and Infrastructure Security Agency (CISA) describes zero trust in its Zero Trust Maturity Model through five pillars, supported by three cross-cutting capabilities: visibility and analytics, automation and orchestration, and governance. Organizations progress through four stages: Traditional, Initial, Advanced and Optimal.
| Pillar | What it covers | Example controls |
|---|---|---|
| Identity | Who is asking for access | Multi-factor authentication, single sign-on, passkeys |
| Devices | What they are using | Device inventory, patching, endpoint protection |
| Networks | How traffic flows | Segmentation, encrypted traffic, replacing broad VPN access |
| Applications and workloads | What they are accessing | App-level access rules, secure development |
| Data | What you are protecting | Classification, encryption, data loss prevention |
Zero trust vs traditional perimeter security
| Aspect | Perimeter security (VPN model) | Zero trust |
|---|---|---|
| Trust | Trusted once inside the network | Never implicit; verified per request |
| Access | Broad network access | Access to specific apps and data |
| Verification | Mostly at login | Continuous and context-aware |
| Breach impact | Attackers can move freely | Segmentation limits lateral movement |
| Fit for remote work and cloud | Weak | Strong |
If you use a VPN today, our Surfshark VPN review explains what consumer VPNs do. Business zero trust goes further than a VPN, because it controls access per app instead of per network.
How zero trust works
- A user or device requests access to an app or data.
- A policy engine checks who they are, how healthy their device is and the context of the request.
- If the checks pass, the user gets access only to that specific resource.
- The session is monitored, and access can be revoked if risk changes.
How to get started: a practical roadmap
- Map what you have. List users, devices, apps and sensitive data, and decide what matters most.
- Strengthen identity first. Turn on multi-factor authentication everywhere, ideally phishing-resistant methods like passkeys, and use single sign-on.
- Secure devices. Keep an inventory, enforce updates and require healthy devices for access to sensitive apps.
- Apply least privilege. Remove standing admin rights and review access regularly.
- Segment the network. Limit lateral movement, and replace broad VPN access with app-level access where you can.
- Protect data. Classify it, encrypt it and monitor how it moves.
- Monitor and improve. Collect logs, set alerts and reassess maturity every few months.
Start with your highest-risk apps rather than trying to change everything at once. Business tools such as the one in our business cybersecurity review can help with network access control.
Zero trust in India
Indian organizations are moving, but not evenly. A May 2026 Zoho study found that one in three Indian businesses has not implemented a zero trust framework, while 85% expect to adopt a zero trust strategy within three years. The government is also pushing the idea: at a May 11, 2026 MeitY workshop, states were told to modernize legacy software using secure-by-design principles and zero trust architecture. Alongside this, India’s DPDP Rules, notified in November 2025, phase in data protection obligations through May 2027, and CERT-In requires incidents to be reported within six hours. Zero trust controls such as strong identity checks, access logging and monitoring support both.
Common zero trust mistakes
- Treating it as a product. No single tool delivers zero trust. It is an approach that combines identity, devices, networks, apps and data.
- Trying to do everything at once. Phase the rollout and prove value on high-risk systems first.
- Ignoring the user experience. Controls that are too painful push people to find workarounds.
- Forgetting data and legacy systems. Old apps and sensitive data are often the weakest pillars.
- Overlooking new risks. AI agents and automated tools also need least-privilege access, as we explain in our guide to agentic AI, and impersonation scams show why identity checks matter, as covered in deepfake scams explained.
Frequently asked questions
What is zero trust security in simple words?
Zero trust means never trusting a user, device or app automatically. Every request must be verified, access is limited to what’s needed, and systems are monitored on the assumption that attackers may already be inside.
What are the three principles of zero trust?
Verify explicitly, use least privilege, and assume breach.
What are the five pillars of zero trust?
In CISA’s model they are identity, devices, networks, applications and workloads, and data.
Does zero trust replace a VPN?
Often it replaces broad VPN access with app-level access, though some organizations keep VPNs for specific uses during the transition.
Is zero trust only for large companies?
No. Small teams can start with multi-factor authentication, single sign-on, device updates and least-privilege access.
Conclusion
Zero trust isn’t a product or a one-time project. It is a way of designing security so that trust is earned on every request and a single stolen password doesn’t expose everything. Start with identity and your most important apps, add devices, access and data controls step by step, and measure progress as you go. Explore more in our Cyber Security coverage.