IEEE International Symposium on Information Theory (ISIT)
On an upper bound of the secrecy capacity for a general wiretap channel
H. Koga, N. Sato
Abstract
This paper is concerned with coding theorems for a generalized wiretap channel. In the problem of the wiretap channel it is important to characterize the secrecy capacity, i.e., the maximum achievable rate of information securely transmitted from a sender to a legitimate receiver in the presence of a wiretapper. In our model, channels are not restricted to memoryless channels. We first define the secrecy capacity Csand evaluate Csfrom information-spectrum approach. We give a new upper bound of Csnot including auxiliary random variables and explore conditions under which the obtained upper bound becomes tight for the cascaded wiretap channel