Zero Trust Security - Never Trust, Always Verify

About 2 min read

Zero trust is a security model that trusts no access and verifies everything, regardless of whether it originates inside or outside the network. Whereas traditional perimeter-based security assumed that "the internal network is safe," zero trust takes "Never Trust, Always Verify" as its core principle. With the spread of remote work and the expansion of cloud services, attention to it has grown rapidly. Gartner's 2024 forecast projects that by 2026, 10% of large enterprises will have completed a mature implementation of zero trust.

Historical Background

The concept of zero trust was proposed in 2010 by John Kindervag, an analyst at Forrester Research. At the time, perimeter-based security (the castle-and-moat model) was mainstream, but a series of perimeter breaches by insider attacks and APTs (Advanced Persistent Threats) exposed the limits of the assumption that "the inside is safe." When remote work expanded rapidly during the 2020 COVID-19 pandemic, the boundary of the corporate network itself became blurred, accelerating the adoption of zero trust. In 2021, the U.S. government issued an executive order requiring federal agencies to adopt zero trust.

Basic Principles

The essence of zero trust lies in three principles. First, access to every resource requires authentication and authorization, regardless of location or network. Second, based on the principle of least privilege, users and devices are granted only the minimum access rights necessary. Third, all traffic is inspected and logged to detect anomalous behavior. Through these principles, threats from inside and lateral movement can be effectively prevented.

The design philosophy of zero trust can be studied systematically with zero trust architecture books on Amazon.

Real-World Use Cases

"We are advancing the migration to a zero trust architecture on a two-year plan. First we will phase out the VPN and switch to ZTNA (Zero Trust Network Access), and then we plan to introduce microsegmentation."

Architecture Concept Diagram

Practice and Pitfalls in the Field

A common misconception when adopting zero trust is the idea that "you can achieve it just by buying a product." Zero trust is not a specific product but a security design philosophy, realized by combining multiple technologies such as multi-factor authentication, microsegmentation, and continuous monitoring. The zero trust mindset can also be applied at the individual level. Setting a unique, strong password for every service and enabling two-factor authentication is the personal version of the "always verify" principle. By generating a different random password for each service and using a VPN to encrypt your communications, you can build a zero-trust-style security posture even at the individual level.personal cybersecurity guides (Amazon) are also a practical reference.