Biometric Identification Systems with Noisy Enrollment for Gaussian Sources and Channels.

In the present paper, we investigate the fundamental trade-off of identification, secret-key, storage, and privacy-leakage rates in biometric identification systems for remote or hidden Gaussian sources. We use a technique of converting the system to one where the data flow is in one-way direction to derive the capacity region of these rates. Also, we provide numerical calculations of three different examples for the system.

Information Theoretic Security for Broadcasting of Two Encrypted Sources under Side-Channel Attacks .

In this paper, we propose a theoretical framework to analyze the secure communication problem for broadcasting two encrypted sources in the presence of an adversary which launches side-channel attacks. The adversary is not only allowed to eavesdrop the ciphertexts in the public communication channel, but is also allowed to gather additional information on the secret keys via the side-channels, physical phenomenon leaked by the encryption devices during the encryption process, such as the fluctuations of power consumption, heat, or electromagnetic radiation generated by the encryption devices. Based on our framework, we propose a countermeasure against such adversary by using the post-encryption-compression (PEC) paradigm, in the case of one-time-pad encryption.

Exponential Strong Converse for One Helper Source Coding Problem.

We consider the one helper source coding problem posed and investigated by Ahlswede, Körner and Wyner. Two correlated sources are separately encoded and are sent to a destination where the decoder wishes to decode one of the two sources with an arbitrary small error probability of decoding. In this system, the error probability of decoding goes to one as the source block length goes to infinity.

A Direct Link between Rényi-Tsallis Entropy and Hölder's Inequality-Yet Another Proof of Rényi-Tsallis Entropy Maximization.

The well-known Hölder's inequality has been recently utilized as an essential tool for solving several optimization problems. However, such an essential role of Hölder's inequality does not seem to have been reported in the context of generalized entropy, including Rényi-Tsallis entropy. Here, we identify a direct link between Rényi-Tsallis entropy and Hölder's inequality.

Information Theoretic Security for Shannon Cipher System under Side-Channel Attacks .

In this paper, we propose a new theoretical security model for Shannon cipher systems under side-channel attacks, where the adversary is not only allowed to collect ciphertexts by eavesdropping the public communication channel but is also allowed to collect the physical information leaked by the devices where the cipher system is implemented on, such as running time, power consumption, electromagnetic radiation, etc. Our model is very robust as it does not depend on the kind of physical information leaked by the devices. We also prove that in the case of one-time pad encryption, we can strengthen the secrecy/security of the cipher system by using an appropriate affine encoder.

Exponential Strong Converse for Source Coding with Side Information at the Decoder.

We consider the rate distortion problem with side information at the decoder posed and investigated by Wyner and Ziv. Using side information and encoded original data, the decoder must reconstruct the original data with an arbitrary prescribed distortion level. The rate distortion region indicating the trade-off between a data compression rate and a prescribed distortion level Δ was determined by Wyner and Ziv.