Towards a dynamic and composable model of trust

During their everyday decision making, humans consider the interplay between two types of trust: vertical trust and horizontal trust. Vertical trust captures the trust relationships that exist between individuals and institutions, while horizontal trust represents the trust that can be inferred from the observations and opinions of others. Although researchers are actively exploring both vertical and horizontal trust within the context of distributed computing (e.g., credential-based trust and reputation-based trust, respectively), the specification and enforcement of composite trust management policies involving the flexible composition of both types of trust metrics is currently an unexplored area.