Zero Trust is a security model where no trust is assumed within a known network.
With Zero Trust, there are no assumptions made about the level of trust, and everything is considered untrusted by default. Authentication and authorization occur continuously, rather than just once.
Frameworks like Google's BeyondCorp are built upon that pattern.
Motivation and History
Classical security paradigms traditionally safeguard a particular network perimeter, such as a company intranet.
Once a person is "inside" – for example, by working within the company network or connecting to it through VPN – they are generally deemed trustworthy.
However, with the rise of cloud technologies and microservices, and the fact that people are working from various locations, this security model is insufficient. The network perimeter is constantly evolving and expanding.
This presents challenges for authenticating subjects that previously relied heavily on network segments.
Principles of Zero Trust
Zero Trust assumes that no user, service, or device is trusted by default, regardless of location or network. It requires continuous verification of identity, strict access controls, and consistent monitoring of network activity.
Basic Principles:
- Least Privilege
- Assume Breach
- Strong Identity Verification
- Verify Explicitly
It involves many areas and aspects, including:
- Identities and Identity Awareness
- Device and Device Authentication
- Networking and Firewall
- Application Security (Security by Design, Secure Architecture)
- Infrastructure Security
- Secure Data Handling
- Organization and Culture
- Secure Development and Delivery
- Security Monitoring and Automation
Implementations
In 2009 Google implemented a zero trust architecture referred to as BeyondCorp. It utilizes OAuth and OpenID standards for implementing Authn and Authz, and has influenced the development of modern Zero Trust architectures.
Typical implementations involve using standards and tools for IAM and SSO, such as Keycloak.
Summary
While network segments and VPN connections may still be relevant in specific areas, DCX is increasingly implementing a Zero Trust approach in all solutions, components, and services.
We are currently adopting best practices for Zero Trust, which align with the BeyondCorp framework and utilize the OAuth and OpenID Connect standards.