Physical layer security for trustworthy and resilient 6G systems (6G-PHYSEC) Deliverable D1.1: Trustworthy 6G: Definition, key characteristics, and initial assessment framework

This report presents the initial outcomes of the collaborative work conducted by Working Group 1 of the 6G-PHYSEC COST Action, focusing on the development of Trustworthy 6G systems. The primary challenge addressed during this initial phase has been to establish a unified and actionable understanding of trustworthiness in the context of 6G, recognizing it as a measurable and context-dependent property of the system.

The report explores the foundational aspects of trustworthiness, including its definition, the identification of relevant attributes, the development of appropriate metrics, and the formulation of an assessment methodology. Trustworthiness is conceptualized as an objective property of the system, characterized by quantifiable attributes such as security, reliability, privacy, resilience, integrity, compliance and safety, and adaptability. These attributes are inherently dependent on specific use cases, which necessitates flexible and
context-aware evaluation approaches.

To address this need, the report introduces a structured assessment framework based on a five-step process. This process begins with (i) the identification of the application domain, followed by (ii) threat identification and risk analysis, (iii) mapping of metrics to trustworthiness attributes, (iv) domain-specific scoring, and concludes with (v) a labeling approach inspired by energy efficiency labels. This labeling system is designed to provide intuitive and accessible insights into the trustworthiness of a system across different application scenarios.

Additionally, the report highlights several emerging considerations that are expected to shape the future of trustworthy 6G systems. These include advancements in physical-layer authentication, enhanced resilience
in lower network layers, the integration of quantum-resistant security mechanisms, and the incorporation of sustainability aspects.

The work presented in this report is the result of coordinated efforts within focused task groups and is intended to serve as a foundation for future research and standardization activities in the design and implementation of secure, reliable, and trustworthy 6G networks.