SoK: Credential-Based Trust Management in Decentralized Ledger Systems

TL;DR

This paper surveys credential-based trust management systems in decentralized ledger contexts, identifying a gap between theory and practice. It introduces a two-dimensional framework combining trust lifecycle stages with architectural layers to classify DTMS solutions. It provides a taxonomy and evaluation criteria focusing on dynamicity, privacy, scalability, and explainability, and surveys representative systems such as CA-based, MAKI, BB RM, DART, and DID/VC/SSI approaches. The findings highlight challenges in privacy of trust data, scalability of blockchain components, and explainability of verification decisions, and outline directions like governance design, graph-based trust modelling, privacy-preserving verification, and SSI integration to improve real-world deployments.

Abstract

Trust management systems (TMS) are crucial for managing trust in distributed environments. The rise of decentralized systems and blockchain has sparked interest in credential-based decentralized trust management systems (DTMS). This paper bridges the gap between theory and practice through a systematic review of credential-based DTMS. We analyze existing DTMS solutions through multiple dimensions, including their architectural designs, credential mechanisms, and trust evaluation models. Our survey provides a detailed taxonomy of credential-based DTMS approaches and establishes comprehensive evaluation criteria for assessing DTMS implementations. Through extensive analysis of current systems and implementations, we identify critical challenges and promising research directions in the field. Our examination offers valuable insights for researchers and practitioners working on DTMS, particularly in areas such as access control, reputation systems, and blockchain-based trust frameworks.

Figures (2)

• Figure 1: Three-Phase Sequential Classification
• Figure 2: Three-Layer Spatial Classification