After ratcheting attracted attention mostly due to practical real-world protocols, recently a line
of work studied ratcheting as a primitive from a theoretic point of view. Literature in this line …

We investigate whether modern messaging apps achieve the strong post-compromise
security guarantees offered by their underlying protocols. In particular, we perform a black …

Ratcheting protocols let parties securely exchange messages in environments in which state
exposure attacks are anticipated. While, unavoidably, some promises on confidentiality and …

Following up mass surveillance and privacy issues, modern secure communication
protocols now seek strong security, such as forward secrecy and post-compromise security …

This thesis explores security goals in the instant messaging setting and backup solutions for
messages and media, both in the case where the device is still available (but has limited …

Protecting communication cryptographically is usually considered and realized modularly:
Protocols for protecting the actual payload utilize session keys that are exchanged by other …