TC: Small: Collaborative Research: Towards a Dynamic and Composable Model of Trust

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

People rely on two types of trust when making everyday decisions: vertical and horizontal trust. Vertical trust captures trust relationships between individuals and institutions, while horizontal trust represents the trust inferred from the observations and opinions of other peers. Although significant benefit could be realized by combining horizontal and vertical trust mechanisms, they have evolved independently in computing systems. This project focuses on developing a composable trust model capable of tightly coupling vertical and horizontal trust in a manner that is both amenable to formal analysis and efficiently deployable. This research advances the state of the art in trust management through a series of innovative results, including the design of a unified framework for specifying composite trust policies and the design and analysis of efficient algorithms for policy evaluation. The composite trust management approach championed by this project also enables policy authors to move beyond simple proof of compliance to identify the "top-k" preferred users satisfying security policies including subjective assessments. The beneficiaries of this research range from administrators of traditional computing systems who can better incorporate previous history into their decision-making processes, to users in social networks who can more carefully manage the exposure of their personal data.