In the last couple of years, cloud and web services have become more and more popular. Since Snowden we know for sure that intelligence agencies have access to the data storage of an service provider, either by (forced) cooperation, or espionage. Thus, to protect our privacy we have to encrypted our data before hand it over to our service provider (data holder). But this approach contradicts the very idea of a web service where the data holder have to process our data in one way or an other. Therefore, we need new cryptographic techniques to enable the data holder to perform operation on encrypted data. One of the most important operations for cloud storage or database based web/cloud services is the search operation. In this talk we focus on the very familiar cloud storage scenario. Because in this scenario, It is obvious, that the user (data owner) do not want to perform the search by himself. This should be a service offered by the data holder. We will present different practical approaches to achieve searchable ciphertext, namely one with an index and one with cleverly encrypted words.

Note that no PhD is required to attend this talk ;-)

Tobias Mueller, Christian Forler