Trust Assessment from Observed Behavior: Toward and Essential Service for Trusted Network Computing

Modern distributed information systems handle increasingly critical data and computation, but there is no systematic way to assess whether a given part of the system can be entrusted with such data and computation on a continuous basis. In a highly interconnected networked environment, components with varying levels of trustworthiness must interact with each other. Occurrence and spread of attack induced failure imply that hosts once trusted cannot remain equally trusted all the time. System components and human operators can benefit from a scheme that assesses the trustworthiness of hosts i.e., the confidence that individual hosts are not corrupt, on a continuous basis by adjusting and adapting their behavior when a host´s trustworthiness diminishes. In this work in progress report we present an accusation based trust assessment scheme