A critical analysis of Zero Trust Architecture (ZTA)

Zero Trust (ZT) has become a very hot approach for building secure systems, promoted by industry and government as a new way to produce systems with a high degree of security. ZT is based on not trusting any request for accessing resources. Because of the possibility of increasing the security of enterprise systems there has been a large amount of publication on different aspects of this strategy. It is then important to evaluate if its claims are true. We have used security patterns to design and evaluate security architectures and we apply here this method to analyze the expectations of this strategy. We relate the ideas behind ZT to the accumulated knowledge of security and attempt to answer some questions about the value and possibilities of this technology. In general, industry publications are vague about the technical aspects of these systems, ignore past security knowledge, and there are few reports describing actual experience building and using ZT architectures. Is Zero Trust Architecture (ZTA) the ideal architecture to build secure systems? To obtain a deeper understanding of this architecture, we analyze its pattern structure and provide a sketch of its reference architecture built as an aggregation of security patterns. As any system architecture, regardless of the way it has been constructed, represents a system, we also consider its threats. Finally, we provide directions for research on this area.