Zero Trust Approach Explained: A Comprehensive Security Methodology

In today's digital landscape, where cyber threats are on the rise and regulatory demands are increasingly stringent, organisations across sectors, including public agencies and businesses in trade, are adopting the Zero Trust Security model. This approach, first described by Paul Marsh in 1994 and further specified by NIST in 2018, represents a significant mindset shift towards network defense, both within and at the network's perimeters.

The Zero Trust model is a perimeterless security approach that does not trust users, devices, applications, or data. It emphasises the importance of assuming a compromise, using context and identity as the basis for access decisions, data encryption, secure authentication, and monitoring for anomalies.

A crucial step in implementing Zero Trust involves systematically removing implicit trusts within the network. For instance, organisations should start by identifying and securing high-risk assets. This process involves checking which users can access these assets, the required authentications, and their permissions. Permissions should be granted based on security settings such as patch levels, operating system version, and installed security solutions on the endpoint.

Monitoring data traffic is essential for early detection of cyber attacks. Network analysis tools and log management & SIEM systems are used to detect unusual behaviour or suspicious actions. Changes in IT infrastructure should also be considered in the individual Zero Trust rulebook.

Key approaches for implementing Zero Trust also include the use of Multi-Factor Authentication (MFA), a critical measure for activating the Zero Trust security model. In the context of remote work, where users are not verified through access controls or social interaction, MFA plays an even more significant role in securing data and traffic.

The practical implementation of the Zero Trust security model involves controlling all areas of IT and thoroughly testing rules and measures before activation. It's also important to limit user access permissions to what is needed for their "normal work". The fewer permissions users and devices have, the less damage a compromised user or endpoint can cause.

Zero Trust must become part of the corporate culture and be viewed as an ongoing process. AI-integrated technologies can recognise anomalies faster and more comprehensively, but are cost-intensive. Organisations aiming to achieve Zero Trust must be prepared for this investment.

German organisations, like some public sector agencies and companies in trade, have already begun implementing Zero Trust Security models since 2022. They use technologies from companies like eperi for data encryption as an early Zero Trust layer.

In conclusion, the Zero Trust Security model offers a robust and proactive approach to network security. By adopting this model, organisations can distribute risks, remain capable of acting, and minimise the damage caused by successful attacks.