Information-Theoretic Key Agreement: From Weak to Strong Secrecy for FreeInformation-Theoretic Key Agreement • September 13th, 2020
Abstract. One of the basic problems in cryptography is the generation of a common secret key between two parties, for instance in order to com- municate privately. In this paper we consider information-theoretically secure key agreement. Wyner and subsequently Csisza´r and Korner de- scribed and analyzed settings for secret-key agreement based on noisy communication channels. Maurer as well as Ahlswede and Csisza´r gen- eralized these models to a scenario based on correlated randomness and public discussion. In all these settings, the secrecy capacity and the secret-key rate, respectively, have been defined as the maximal achiev- able rates at which a highly-secret key can be generated by the legitimate partners. However, the privacy requirements were too weak in all these definitions, requiring only the ratio between the adversary’s information and the length of the key to be negligible, but hence tolerating her to ob- tain a possibly substantial amount of information about the result
Information-Theoretic Key AgreementInformation-Theoretic Key Agreement • August 29th, 2022
Information-Theoretic Key Agreement of Multiple Terminals - Part II: Channel ModelInformation-Theoretic Key Agreement • October 9th, 2009
This is the second part of a two-part paper on information-theoretically secure secret key agreement. This part covers the secret key capacity under the channel model. In this model, multiple terminals wish to create a shared secret key that is secure from an eavesdropper with unlimited computational resources. The terminals are all connected to a noiseless and authenticated but unsecure channel, called the “public channel”. Furthermore, the terminals have access to a secure but noisy discrete memoryless broadcast channel (DMBC). The first terminal can choose a sequence of inputs to the DMBC, which has outputs at the other terminals and at the eavesdropper. After each channel use, the terminals can engage in arbitrarily many rounds of interactive authenticated communication over the public channel. At the end, each legitimate terminal should be able to generate the secret key. In this paper, we derive new lower and upper bounds on the secrecy capacity. In each case, an example is provi
Information-Theoretic Key Agreement of Multiple Terminals - Part I: Source ModelInformation-Theoretic Key Agreement • January 23rd, 2008
Information-Theoretic Key Agreement of Multiple Terminals - Part IInformation-Theoretic Key Agreement • October 9th, 2009
ity bound of |X1||X2||Z| on the size of the alphabet set of J. Therefore the infimum over finite random variables J is a minimum. It is enough to prove that minJ I(X1; X2|J) + I(X1X2; J|Z) strictly improves the Renner-Wolf double intrinsic information upper bound. In order to prove that
Information-Theoretic Key Agreement of Multiple Terminals - Part II: Channel ModelInformation-Theoretic Key Agreement • January 23rd, 2008
