Secure Open Systems for Protecting Privacy and Digital Services

Abstract

This paper describes and analyzes a system architecture that enables consumers to access services and content from multiple providers without jeopardizing the privacy interests of consumers or the intellectual property rights of providers. In order to satisfy these highly desirable objectives, we argue for the necessity of a Trust Server that mediates the conferral and revocation of trust relationships between consumers and providers. The system also calls for the deployment of programmable security coprocessors at vulnerable sites requiring protection, namely at the Trust Server and at each consumer. We define the specific requirements of consumer-side Coprocessors, and their server-side counterparts denoted as Hardware Security Modules (HSMs). A single Coprocessor serves multiple providers by allocating to each of them a virtualized trusted computing environment for software execution and data manipulation. Bearing in mind that the tamper-resistance offered by Coprocessors is subject to more stringent economic pressures than that offered by HSMs, we include in our architecture containment capabilities that prevent compromised Coprocessors from causing damage disproportionate to their numbers. We explain the specific challenges faced with providing containment capabilities while protecting consumer privacy, given that a single Coprocessor must serve the needs of multiple providers. The simultaneous attainment of these goals is one of the highlights of our architecture.