Free space optical secret key agreement

A Randomized Space-Time Transmission Scheme for Secret-Key Agreement

In contrast to the pessimistic view on perfect secrecy, studies on information-theoretic secrecy have shown that perfect secrecy may be possible in practice. A typical example is the Wyner’s wire-tap channel concept. However, existing approaches mostly depend on unrealistic noise or error-rate assumptions. We propose a more practical way in this paper which uses advanced space-time transmission...

Information-Theoretic Secret Key Agreement

Towards Characterizing When Information-Theoretic Secret Key Agreement Is Possible

This paper is concerned with information-theoretically secure secret key agreement in the general scenario where three parties,quence of random bits broadcast by a satellite. We consider the problem of determining for a given distribution PXY Z whether Alice and Bob can in principle, by communicating over an insecure channel accessible to Eve, generate a secret key about which Eve's information...

Secret-key agreement over unauthenticated public channels III: Privacy amplification

This is the third part of a three-part paper on secret-key agreement secure against active adversaries. Here, we consider the special case where the legitimate partners already share a mutual string which might, however, be partially known to the adversary. The problem of generating a secret key in this case has been well studied in the passive-adversary model—for instance in the context of qua...

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 ...