Efficient Key Updates through Subscription Re-encryption for Privacy-Preserving Publish/Subscribe
Abstract Content-based publish/subscribe (pub/sub) is an appealing information dissemination paradigm for distributed systems. Consumers of data subscribe to a pub/sub service, typically offered through a distributed broker overlay, and indicate their interests as constraints over the information content. Publishers generate the information flow, which the brokers filter and route to the interested subscribers. Protecting the information confidentiality, and in particular the interests of subscribers, is an important concern when brokers are located in untrusted domains such as public clouds. Encrypted matching techniques allow untrusted brokers to store encrypted subscriptions and match them against encrypted publications. Updates of encryption keys regularly happen in such contexts due to changes in trust relations. These key updates cause the invalidation of stored encrypted subscriptions and force subscribers to re-encrypt and re-submit them. This long and costly operation impacts the pub/sub service continuity and performance. In this paper, we propose a novel technique that allows updating encrypted subscriptions directly at the brokers while maintaining privacy guarantees. We present an implementation of the technique for the ASPE encrypted matching scheme and prove the security of our extension. We evaluate its practical effectiveness through a prototype implementation including a dependable key dis- tribution protocol. Our experiments show the ability to handle key updates while preserving service continuity and performance.
Keywords publish/subscribe, confidentiality, key management
Citation E. Onica, et al., "Efficient Key Updates through Subscription Re-encryption for Privacy-Preserving Publish/Subscribe," in Middleware'15: The 16th ACM/IFIP/USENIX International Middleware Conference, Vancouver, Canada, 2015, .
Type Conference paper (English)
Name of conference Middleware'15: The 16th ACM/IFIP/USENIX International Middleware Conference (Vancouver, Canada)
Date of conference 7-12-2015
Publisher ACM
URL http://dx.doi.org/10.1145/2814576.2814805
Related project SRT-15: Intelligence Push in the Enterprise Realm