Attribute-Based Encryption as a Service for Access Control in Large-Scale Organizations

In this work, we propose a service infrastructure that provides confidentiality of data in the cloud. It enables information sharing with fine-grained access control among multiple tenants based on attribute-based encryption. Compared to the standard approach based on access control lists, our encryption as a service approach allows us to use cheap standard cloud storage in the public cloud and to mitigate a single point of attack. We use hardware security modules to protect long-term secret keys in the cloud. Hardware security modules provide high security but only relatively low performance. Therefore, we use attribute-based encryption with outsourcing to integrate hardware security modules into our micro-service oriented cloud architecture. As a result, we achieve elasticity, high performance, and high security at the same time.