Privacy-preserving content-based publish/Subscribe networks

Privacy and confidentiality are crucial issues in content-based publish/subscribe (CBPS) networks. We tackle the problem of end-user privacy in CBPS. This problem raises a challenging requirement for handling encrypted data for the purpose of routing based on protected content and encrypted subscription information. We suggest a solution based on a commutative multiple encryption scheme in order to allow brokers to operate in-network matching and content based routing without having access to the content of the packets. This is the first solution that avoids key sharing among end-users and targets an enhanced CBPS model where brokers can also be subscribers at the same time.