On the internet, cryptographic protocols are nowadays ubiquitous. They are used to establish secure communication channels, sign electronic documents, securely store private data remotely, enable decentralized payments and countless other tasks that are of raising interest in our networked world.
There is an increasing demand for new protocols, mainly for two reasons. Firstly, security of existing protocols might break due to the discovery of new attacks, or the security might become too weak for a newly arising application of the protocol. In this case, protocols with stronger security guarantees need to be found. Secondly, the increasing digitalization of our society and invention of new technologies, like blockchain or cloud computing, raise new demands and ideas for cryptographic protocols. The goal of our research is to find realistic security models for such new applications and to develop cryptographic protocols with provable security guarantees.