Zero Trust Overview
What is it?
Zero Trust is a security framework built on one principle: never trust, always verify. Instead of the traditional model where everyone inside the corporate network is trusted, Zero Trust requires every user and device to prove their identity and meet security requirements before accessing any resource — whether they're in the office, at home, or at a coffee shop.
Cloudflare's Zero Trust platform is called Cloudflare One. It's a full SASE (Secure Access Service Edge) platform that replaces legacy VPNs, firewalls, and other network hardware with cloud-delivered security running on Cloudflare's global network.
What problem does it solve?
The traditional security model (sometimes called "castle and moat") assumed that everything inside the corporate network was safe and everything outside was dangerous. This model broke when:
- Remote work became the norm — employees aren't in the office anymore.
- Cloud migration moved applications out of the corporate data center.
- VPNs are terrible — they're slow, they give users access to the entire network (not just what they need), and they create a single point of failure.
- Lateral movement — once an attacker gets past the perimeter (the "moat"), they can move freely inside the network.
Zero Trust eliminates the concept of a trusted internal network. Every request is authenticated and authorized, regardless of where it comes from.
How does it work?
Cloudflare One replaces legacy network security with cloud-delivered services:
- Identity verification: Every access request checks who the user is (via identity providers like Okta, Google, Azure AD).
- Device posture: Checks whether the device meets security requirements (OS updates, disk encryption, endpoint protection).
- Least-privilege access: Users only get access to the specific applications and resources they need — not the whole network.
- Continuous evaluation: Security isn't just checked at login — it's continuously reassessed throughout the session.
The platform includes several products we'll cover in upcoming lessons: Cloudflare Access (ZTNA), Gateway (SWG), Browser Isolation, and Email Security.
Why it matters strategically
Act 2 represents Cloudflare's biggest TAM expansion. While Act 1 targets web-facing applications, Act 2 targets the entire corporate security stack — a market worth tens of billions of dollars. Cloudflare competes with Zscaler, Palo Alto Networks, and Cisco in this space. The strategic advantage is that Cloudflare can deliver Zero Trust on the same network that already handles CDN and DDoS protection, giving customers a single vendor for both public-facing and internal security.