TY - JOUR

T1 - Conditional information leakage given eavesdropper’s received signals in wiretap channels

AU - Jitsumatsu, Yutaka

AU - Michiwaki, Ukyo

AU - Oohama, Yasutada

N1 - Funding Information:
The first author would like to thank Professor Ryutaro Matsu-moto for suggesting the use of q-binomial coefficients, also called Gaussian binomial coefficients. This suggestion lead to the analysis discussed in Sect. 4.3. He also would like to thank Professor Tomohiro Ogawa for suggesting the use of characteristic function rather than probability generating function. This change made the discussion rigorous. This work was supported by JSPS KAKENHI Grant Numbers JP16K00333, JP17K00308, JP18H01438, and JP19K12156.
Publisher Copyright:
Copyright © 2021 The Institute of Electronics, Information and Communication Engineers

PY - 2021/1/1

Y1 - 2021/1/1

N2 - Information leakage in Wyner’s wiretap channel model is usually defined as the mutual information between the secret message and the eavesdropper’s received signal. We define a new quantity called “conditional information leakage given the eavesdropper’s received signals,” which expresses the amount of information that an eavesdropper gains from his/her received signal. A benefit of introducing this quantity is that we can develop a fast algorithm for computing the conditional information leakage, which has linear complexity in the code length n, while the complexity for computing the usual information leakage is exponential in n. Validity of such a conditional information leakage as a security criterion is confirmed by studying the cases of binary symmetric channels and binary erasure channels.

AB - Information leakage in Wyner’s wiretap channel model is usually defined as the mutual information between the secret message and the eavesdropper’s received signal. We define a new quantity called “conditional information leakage given the eavesdropper’s received signals,” which expresses the amount of information that an eavesdropper gains from his/her received signal. A benefit of introducing this quantity is that we can develop a fast algorithm for computing the conditional information leakage, which has linear complexity in the code length n, while the complexity for computing the usual information leakage is exponential in n. Validity of such a conditional information leakage as a security criterion is confirmed by studying the cases of binary symmetric channels and binary erasure channels.

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U2 - 10.1587/transfun.2020EAP1017

DO - 10.1587/transfun.2020EAP1017

M3 - Article

AN - SCOPUS:85099223823

SN - 0916-8508

VL - 104

SP - 295

EP - 304

JO - IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences

JF - IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences

IS - 1

ER -