Editing Aggregation of sensitive data (section)

==Participatory trust and delegated trust==
The two main security models considered for secure computing are participatory trust and delegated trust. In the participatory trust model, data owners perform a collective computation which is private by-design. The participants thus bear the responsibility for the privacy. In the delegated trust model, a third party aggregates the data from various participants and runs the computation. He is responsible for the privacy of the process.
Various security issues arise from these situations. In the delegated trust model, the first step is to centralize the data. This requires to secure data in-transit as well as stored data. The second step is to compute over the securely stored data. In the participatory trust model, the protocol executed by the participants should be private by-design.

In both cases, quantum networks can increase security. In the example developed above, the aggregation is performed on healthcare data. These are very sensitive data that require carefully designed security. In particular, the long-term security that is inherent to quantum cryptography could strengthen the security of communication and storage in the case of delegated trust, and privacy by-design in the case of participatory trust.