Zero Trust Security | What's a Zero Trust Network?

Zero trust is a security model based on the principle of maintaining strict access controls and not trusting anyone by default, even those already inside the network perimeter.

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Zero Trust

Learning Objectives

After reading this article you will be able to:

  • Define zero trust security
  • Outline the technologies and principles behind zero trust

What is zero trust security?

Zero trust security is an IT security model that requires strict identity verification for every person and device trying to access resources on a private network, regardless of whether they are sitting within or outside of the network perimeter. No single specific technology is associated with zero trust; it is a holistic approach to network security that incorporates several different principles and technologies.

Traditional IT network security is based on the castle-and-moat concept. In castle-and-moat security, it is hard to obtain access from outside the network, but everyone inside the network is trusted by default. The problem with this approach is that once an attacker gains access to the network, they have free reign over everything inside.

This vulnerability in castle-and-moat security systems is exacerbated by the fact that companies no longer have their data in just one place. Today, information is often spread across cloud vendors, which makes it more difficult to have a single security control for an entire network.

Zero trust security means that no one is trusted by default from inside or outside the network, and verification is required from everyone trying to gain access to resources on the network. This added layer of security has been shown to prevent data breaches. A recent IBM-sponsored study demonstrated that the average cost of a single data breach is over $3 million. Considering that figure, it should come as no surprise that many organizations are now eager to adopt a zero-trust security policy.

What are the main principles and technologies behind zero trust security?

The philosophy behind a zero trust network assumes that there are attackers both within and outside of the network, so no users or machines should be automatically trusted.

Another principle of zero trust security is least-privilege access. This means giving users only as much access as they need, like an army general giving soldiers information on a need-to-know basis. This minimizes each user’s exposure to sensitive parts of the network.

Zero trust networks also utilize microsegmentation. Microsegmentation is the practice of breaking up security perimeters into small zones to maintain separate access for separate parts of the network. For example, a network with files living in a single data center that utilizes microsegmentation may contain dozens of separate, secure zones. A person or program with access to one of those zones will not be able to access any of the other zones without separate authorization.

Multi-factor authentication (MFA) is also a core value of zero trust security. MFA simply means requiring more than one piece of evidence to authenticate a user; just entering a password is not enough to gain access. A commonly seen application of MFA is the 2-factor authorization (2FA) used on popular online platforms like Facebook and Google. In addition to entering a password, users who enable 2FA for these services must also enter a code sent to another device, such as a mobile phone, thus providing two pieces of evidence that they are who they claim to be.

In addition to controls on user access, zero trust also requires strict controls on device access. Zero trust systems need to monitor how many different devices are trying to access their network and ensure that every device is authorized. This further minimizes the attack surface of the network.

What is the history of zero trust security?

The term ‘zero trust’ was coined by an analyst at Forrester Research Inc. in 2010 when the model for the concept was first presented. A few years later, Google announced that they had implemented zero trust security in their network, which led to a growing interest in adoption within the tech community.

How to implement zero trust security

Up until now, zero trust required detailed implementation by security engineers, focusing on the core principles and technologies listed above. But thanks to the introduction of Cloudflare Access, any organization can now quickly and easily implement a zero-trust security system on their network.