D.2 Future-Proofing Key Exchange Protocols

- Jacqueline Brendel -

Secure connections are at the heart of many applications, ranging from banking and online shopping to our everyday web browsing and instant messaging communications.

For secure and efficient communication, it is necessary that the communicating parties (e.g. your browser and a web server) establish a shared cryptographic secret key.

So-called key exchange protocols allow to do just this. In these protocols, the parties communicate over an insecure channel in the presence of a powerful adversary that has control over the entire network and may, for example, arbitrarily modify, delay, or drop messages. At the end of the protocol execution, the parties hold a shared secret which they can then use to encrypt their ensuing communications.

In the last few years, it has become more and more acknowledged that cryptographic protocols should undergo a rigorous security analysis – if possible already at design time. We have also seen that the advances in computational power and cryptanalytic capabilities often render still widely deployed cryptographic algorithms insecure. Especially the advent of quantum computers will have a devastating effect on many cryptographic schemes in use today and thus also on key exchange protocols. In my work I focus on developing advanced security models and assumptions for the analysis of key exchange protocols that can capture these new scenarios and demands.

Tandem partner: D.4 , D.5