Symbolic secrecy of exchanged keys is arguably one of the most important notions of secrecy shown with automated proof tools. It means that an adversary restricted to symbolic operations on terms can never get the entire key into its knowledge set. Cryptographic key secrecy essentially means computational indistinguishability between the real key and a random one, given the view of a much more ...

We establish the Ahlswede dichotomy for arbitrarily varying classicalquantum wiretap channels, i.e., either the deterministic secrecy capacity of the channel is zero, or it equals its randomness-assisted secrecy capacity. We analyze the secrecy capacity of these channels when the sender and the receiver use various resources. It turns out that randomness, common randomness, and correlation as r...

Inmany applications of networked information systems, the need to share information often has to be balanced against the need to protect secret information from unintended disclosure, e.g., due to copyright, privacy, security, or commercial considerations. We study the problem of secrecy-preserving reasoning, that is, answering queries using secret information, whenever it is possible to do so,...

Two styles of definitions are usually considered to express that a security protocol preserves the confidentiality of a data s. Reachability-based secrecy means that sshould never be disclosed while equivalence-based secrecy states that two executions of a protocol with distinct instances for s should be indistinguishable to an attacker. Althoughthe second formulation ensures a higher l...

We propose a general framework of secrecy and preservation of secrecy for labeled transition systems. Our definition of secrecy is parameterized by the distinguishing power of the observer, the properties to be kept secret, and the executions of interest, and captures a multitude of definitions in the literature. We define a notion of secrecy preserving refinement between systems by strengtheni...

Scholars have grown concerned that the commercialization of academic science is increasing secrecy at the expense of cooperation and information sharing. Using data from comparable surveys of academic scientists in three fields (experimental biology, mathematics and physics), we test whether scientists have become more competitive and more secretive over the last 30 years. We also use the recen...

We determine the secrecy capacities of arbitrarily varying quantum channels. Both secrecy capacity with average error probability and with maximal error probability are derived. The code we construct fulfills a stringent secrecy requirement, which is called the strong code concept. We determine when the secrecy capacity is a continuous function of the system parameters and completely characteri...