Trust-privacy tradeoffs in distributed systems

In distributed systems, it is often needed to establish trust before entities interact together. This trust establishment process involves making each entity ask for some credentials from the other entity, which implies some privacy loss for both parties. We propose a model for achieving the right privacy-trust tradeoff in distributed environments. Each entity aims to join a group in order to protect its privacy. Interaction between entities is then replaced by interaction between groups on behalf of their members. Data sent between groups is saved from dissemination by a self-destruction process. Simulations performed on the proposed model using the Aglets platform show that entities requesting a service need to give up more private information when their past experiences are not good, or when the server entity is of a paranoid nature. The privacy loss in all cases is quantified and controlled.