Stop 04 · Core Security ConceptsTopics · 7/10

Zero Trust Architecture

In short

The old idea was 'inside the office network means trusted'. Attackers loved that. Zero trust checks every request, every time, no matter where it comes from.

A security model assuming no user or system should be trusted by default, even inside the network perimeter — every request is verified regardless of where it originates.

The blob hands a blank boarding pass to a guard with a scanner, with a security queue behind.

Think of it like this

Checks at the airport

You show ID at the entrance, again at security, and once more at the boarding gate. Being inside the terminal doesn't get you onto any plane you like. Zero trust treats every network the same way: being inside proves nothing.

Watch it happen

Every request is checked on its own

Employee

Policy engine

Device check

HR app

open HR app

1/6Priya asks to open the HR app. It doesn't matter if she's at the office or at home.

The big ideas

What you need to know

Verify explicitly

Use identity, device health, location and behaviour for every access decision, not network location.

Least privilege

Grant access to specific apps for a limited time, instead of a whole network.

Assume breach

Design as if attackers are already inside. Segment, log everything and limit how far they could spread.

A process, not a product

No single tool makes you zero trust. It's built step by step: identity first, then devices, apps and data.

Save yourself the pain

Common mistakes

Oops

Buying one 'zero trust' product and calling it done.

Do this instead

Zero trust is an approach. Start with strong identity and MFA, then add device checks and per-app access.

Oops

Still letting anyone on the VPN reach every server.

Do this instead

Give access per application, based on who and what device is asking.

Your mission

Zero-trust your college

~25 min

Quick check

An attacker plugs a laptop into an office network port. Under zero trust, what can it reach?

Go deeper

1Learn the core zero trust principle: 'never trust, always verify'.
2Compare zero trust to the traditional perimeter-based security model it's replacing.
3Understand why zero trust has become more relevant as remote work blurs traditional network boundaries.