We study the problem of remote state estimation, in the presence of an eavesdropper. An authorized user estimates the state of a linear plant, based on the data received from a sensor, while the data may also be intercepted by the eavesdropper. To maintain confidentiality with respect to state, we introduce a novel control-theoretic definition of perfect secrecy requiring that the user’s expect...

• Definition of perfect secrecy • One-time pad and optimality (Shannon's theorem) • Definition of statistical one-time MAC and construction. Historically, cryptography was treated as a practical problem with practical applications. Many of these schemes were insecure due to a lack of a mathematical foundation combined with no understanding of desirable properties in cryptography systems. Howeve...

We present a new idea to design perfectly secure information exchangeprotocol, based on a new form of randomness, called « Deep Randomness »,generated in such a way that probability distribution of the output signal ismade unknowledgeable for an observer. By limiting, thanks to DeepRandomness, the capacity of the opponent observer to perform bayesianinference over public...

Perfect forward secrecy, one of the possible security features provided by key establishment protocols, concerns dependency of a session key upon long-term secret keys (symmetric or asymmetric). The feature promises that even if a long-term private key is disclosed to any adversary, the session keys established in the protocol runs using the long-term key would not be compromised. The importanc...

This paper reviews the relations between information theory and cryptography, from Shannon's foundation of information theory to the most recent developments in unconditionally-secure key-agreement protocols. For a long time, information theory has mainly been used in cryptography to prove lower bounds on the size of the secret key required to achieve a certain level of security in secrecy and ...

In 1949, Shannon proved the perfect secrecy of the Vernam cryptographic system (One-Time Pad or OTP). It has generally been believed that the perfectly random and uncompressible OTP which is transmitted needs to have a length equal to the message length for this result to be true. In this paper, we prove that the length of the transmitted OTP actually contains useful information and could be ex...

We study a special case of Willems’s two-user multiaccess channel with partially cooperating encoders from security perspective. This model differs from Willems’s setup in that only one encoder, Encoder 1, is allowed to conference, Encoder 2 does not transmit any message, and there is an additional passive eavesdropper from whom the communication should be kept secret. For the discrete memoryle...

In this paper, we consider the achievable sum secrecy rate in full-duplex wiretap channel in the presence of an eavesdropper and imperfect channel state information (CSI). We assume that the users participating in full-duplex communication and the eavesdropper have single antenna each. The users have individual transmit power constraints. They also transmit jamming signals to improve the secrec...