Technical report of IEICE. ISEC

Secret Key Agreement by Reliability Information of Signals in Gaussian Maurer's Model

Masashi Naito, Shun Watanabe, Ryutaroh Matsumoto, Tomohiko Uyematsu

Published Feb 22, 2008• 2 citations

Abstract

We consider the problem of secret key agreement in Gaussian Maurerpsilas Model. In Gaussian Maurerpsilas model, legitimate receivers, Alice and Bob, and a wire-tapper, Eve, receive signals randomly generated by a satellite through three independent memoryless Gaussian channels respectively. Then Alice and Bob generate a common secret key from their received signals. In this model, we propose a protocol for generating a common secret key by using the result of soft-decision of Alice and Bobpsilas received signals. Then, we calculate a lower bound on the secret key rate in our proposed protocol. As a result of comparison with the protocol that only uses hard-decision, we found that the higher rate is obtained by using our protocol.

Related papers

Secret key agreement by reliability information of signals in Gaussian Maurer’s Model

Masashi Naito, Shun Watanabe, Ryutaroh Matsumoto +1 more

We consider the problem of secret key agreement in Gaussian Maurer’s Model. In Gaussian Maurer’s model, legitimate receivers, Alice and Bob, and a wire-tapper, Eve, receive signals randomly generated by a satellite through three independent memoryless Gaussian channels respectively. Then Alice and Bob generate a common secret key from their received signals. In this model, we propose a protocol for generating a common secret key by using the result of soft-decision of Alice and Bob’s received signals. Then, we calculate a lower bound on the secret key rate in our proposed protocol. As a result of comparison with the protocol that only uses hard-decision, we found that the higher rate is obtained by using our protocol.

IEEE International Symposium on Information Theory (ISIT)Jul 1, 200810 citations

Secret Key Agreement by Soft-Decision of Signals in Gaussian Maurer's Model

Masashi Naito, Shun Watanabe, Ryutaroh Matsumoto +1 more

We consider the problem of secret key agreement in Gaussian Maurer's Model. In Gaussian Maurer's model, legitimate receivers, Alice and Bob, and a wire-tapper, Eve, receive signals randomly generated by a satellite through three independent memoryless Gaussian channels respectively. Then Alice and Bob generate a common secret key from their received signals. In this model, we propose a protocol for generating a common secret key by using the result of soft-decision of Alice and Bob's received signals. Then, we calculate a lower bound on the secret key rate in our proposed protocol. As a result of comparison with the protocol that only uses hard-decision, we found that the higher rate is obtained by using our protocol.

arXiv:0804.2940IEICE Transactions on Fundamentals of Electronics Communications and Computer SciencesJan 1, 200924 citations

Signal Sets for Secret Key Agreement With Public Discussion Based on Gaussian and Fading Channels

Motohiko Isaka, S. Kawata

We study the signal sets for information theoretically secure key agreement with public discussion over the Gaussian and flat fading channels. Alice transmits signals to Bob over a noisy channel while Eve receives signals through an independent noisy channel. By utilizing this noisy resource, Alice and Bob wish to share a secret key on which Eve has a negligible amount of information. We present a protocol that allows Alice and Bob to share a common secret information, and encompass the signal sets for an efficient protocol in information theoretic sense.

IEEE Transactions on Information Forensics and SecurityMar 22, 20117 citations

Unconditionally secure secret key agreement and the intrinsic conditional mutual information

Ueli M. Maurer, Stefan Wolf

This paper is concerned with secret-key agreement by public discussion: two parties Alice and Bob and an adversary Eve have access to independent realizations of random variables X , Y , and Z, respectively, with joint distribution PXY Z . The secret key rate S(X ; Y jjZ) has been defined as the maximal rate at which Alice and Bob can generate a secret key by communication over an insecure, but authenticated channel such that Eve's information about this key is arbitrarily small. We define a new conditional mutual information measure, the intrinsic conditional mutual information between X and Y when given Z, denoted by I(X ; Y#Z), which is an upper bound on S(X ; Y jjZ). The special scenarios where X , Y , and Z are generated by sending a binary random variable R, for example a signal broadcast by a satellite, over independent channels, or where Z is generated by sending X and Y over erasure channels, are analyzed. In the first scenario it can be shown that the secret key rate is str...

May 1, 19971 citation

Unconditionally secure key agreement and the intrinsic conditional information

Ueli M. Maurer, Stefan Wolf

This paper is concerned with secret-key agreement by public discussion. Assume that two parties Alice and Bob and an adversary Eve have access to independent realizations of random variables X, Y, and Z, respectively, with joint distribution P/sub XYZ/. The secret-key rate S(X;Y/spl par/Z) has been defined as the maximal rate at which Alice and Bob can generate a secret key by communication over an insecure, but authenticated channel such that Eve's information about this key is arbitrarily small. We define a new conditional mutual information measure, the intrinsic conditional mutual information between S and Y when given Z, denoted by I(X;Y/spl darr/Z), which is an upper bound on S(X;Y/spl par/Z). The special scenarios are analyzed where X, Y, and Z are generated by sending a binary random variable R, for example a signal broadcast by a satellite, over independent channels, or two scenarios in which Z is generated by sending X and Y over erasure channels. In the first two scenarios it can be shown that the secret-key rate is strictly positive if and only if I(X;Y/spl darr/Z) is strictly positive. For the third scenario, a new protocol is presented which allows secret-key agreement even when all the previously known protocols fail.

IEEE Transactions on Information TheoryMar 1, 1999274 citations

Secrecy via Sources and Channels 1

Vinod M. Prabhakaran, Krishnan Eswaran, Kannan Ramch

Alice and Bob want to share a secret key and to communicate an independent message, both of which they desire to be kept secret from an eavesdropper Eve. We study this problem of secret communication and secret key generation when two resources are available – correlated sources at Alice, Bob, and Eve, and a noisy broadcast channel from Alice to Bob and Eve which is independent of the sources. We are interested in characterizing the fundamental trade-off between the rates of the secret message and secret key. We present an achievable solution and prove its optimality for the parallel channels and sources case when each sub-channel and source component satisfies a degradation order (either in favor of the legitimate receiver or the eavesdropper). This includes the case of jointly Gaussian sources and an additive Gaussian channel, for which the secrecy region is evaluated. I.

Mar 17, 201141 citations