Common Information and Secret Key Capacity

Secret key agreement by public discussion from common information

The problem of generating a shared secret key S by two parties knowing dependent random variables X and I’, respectively, but not sharing a secret key initially, is considered. An enemy who knows the random variable 2, jointly distributed with X and Y according to some probability distribution PXYZ, can also receive all messages exchanged by the two parties over a public channel. The goal of a ...

Information-Theoretic Secret Key Agreement

Secret key Capacity for Wireless Nakagami and Suzuki Fading Channels

Security of wireless transmission is a great challenge in secure communications. Classical methods are based on cryptographic algorithms. These methods require a secret key that must be generated securely between associated parties in communication. Another approach to security is based on wiretap channel concept and is applicable for wireless communications. Because of rather small secrecy cap...

Common randomness and secret key generation with a helper

We consider the generation of common randomness (CR), secret or not secret, by two user terminals with aid from a “helper” terminal. Each terminal observes a different component of a discrete memoryless multiple source. The helper aids the users by transmitting information to them over a noiseless public channel subject to a rate constraint. Furthermore, one of the users is allowed to transmit ...

Common Randomness and Secret Key Capacities of Two-Way Channels

Common Randomness Generation (CRG) and Secret Key Establishment (SKE) are fundamental primitives that are used in information-theoretic coding and cryptography. We study these two problems over the two-way channel model of communication, introduced by Shannon. In this model, the common randomness (CK) capacity is defined as the maximum number of random bits per channel use that the two parties ...