IEEE International Conference on Communication Technology (ICCT)

Some new results on the wiretap channel with causal side information

Bin Dai, Zhuojun Zhuang, A. J. Han Vinck

Published Nov 1, 2012• 4 citations

Abstract

In this paper, the model of wiretap channel has been reconsidered for the case that the main channel is controlled by channel state information (side information), and it is available at the transmitter in a causal manner. Inner and outer bounds are derived on the capacity-equivocation region for this new model, and the secrecy capacity is described and bounded, which provides the best transmission rate with perfect secrecy.

DOI: 10.1109/icct.2012.6511278

Related papers

Some New Results on the Wiretap Channel with Side Information

Bin Dai, Yuan Luo

In this paper, the model of wiretap channel has been reconsidered for the case that the main channel is controlled by channel state information (side information), and it is available at the transmitter in a noncausal manner (termed here noncausal side information) or causal manner (termed here causal side information). Inner and outer bounds are derived on the capacity-equivocation regions for the noncausal and causal manners, and the secrecy capacities for both manners are described and bounded, which provide the best transmission rate with perfect secrecy. Moreover, for the case that the side information is available at the transmitter in a memoryless manner (termed here memoryless side information), both the capacity-equivocation region and the secrecy capacity are determined. The results of this paper extend the previous work on wiretap channel with noncausal side information by providing an outer bound on the capacity-equivocation region. In addition, we find that the memoryless side information can not help to obtain the same secrecy capacity as that of the causal case, and this is different from the well known fact that the memoryless manner can achieve the capacity of the channel with causal side information.

EntropySep 7, 201224 citations

Wiretap Channel with Action-Dependent Channel State Information

Bin Dai, A. J. Han Vinck, Yuan Luo +1 more

In this paper, we investigate the model of wiretap channel with action-dependent channel state information. Given the message to be communicated, the transmitter chooses an action sequence that affects the formation of the channel states, and then generates the channel input sequence based on the state sequence and the message. The main channel and the wiretap channel are two discrete memoryless channels (DMCs), and they are connected with the legitimate receiver and the wiretapper, respectively. Moreover, the transition probability distribution of the main channel depends on the channel state. Measuring wiretapper’s uncertainty about the message by equivocation, inner and outer bounds on the capacity-equivocation region are provided both for the case where the channel inputs are allowed to depend non-causally on the state sequence and the case where they are restricted to causal dependence. Furthermore, the secrecy capacities for both cases are bounded, which provide the best transmission rate with perfect secrecy. The result is further explained via a binary example.

EntropyJan 28, 201314 citations

On the Secrecy Capacity of Wiretap Channels With Side Information at the Transmitter

Hachiro Fujita

The wiretap channel with causal/noncausal side information at the transmitter is an extension of the original wiretap channel of Wyner to the multi-user case and has been investigated by several authors. Although much effort has been made to establish the secrecy capacity, it is still elusive even if the wiretap channel is physically degraded. In this paper, for a physically degraded wiretap channel, we show a lower bound on the secrecy capacity for the causal case and an upper bound for the noncausal case. We also show that under a certain condition, the secrecy capacity for the causal case is the same as that for the noncausal case. To illustrate the usefulness of our theoretical result, we introduce the concept of a symmetric wiretap channel with state, for which the above condition is easily checked, and we give some examples in which the secrecy capacity can be computed numerically.

IEEE Transactions on Information Forensics and SecurityJun 20, 201612 citations

Wiretap channel with strictly causal side information at encoder

Amir Sonee, Ghosheh Abed Hodtani

In this paper, the wiretap channel with side information studied in [2] is revisited for the case in which the side information is available only at the encoder and in a strictly causal manner. We derive a lower bound on the secrecy capacity of the channel based on a coding scheme which consists of block Markov encoding and key generation using the strictly causal state information available at the encoder. In order to provide the secrecy of messages, at the end of each block a description of the state sequence obtained by the encoder is used to generate the key which encrypts the whole or part of the message to be transmitted in the next block. Moreover, for the decoder to be able to decrypt the messages, the description of the sate sequence of each block is sent in common with the message of that block. Also, an upper bound on the secrecy capacity is developed which assumes that the state is noncausally known at the encoder and we prove that it would coincide the lower bound for a special case and results in the secrecy capacity.

Iran Workshop on Communication and Information Theory (IWCIT)May 1, 20147 citations

New outer bounds for wiretap channel with action-dependent states

Xinxing Yin, Liang Pang, Zhi Xue

The action-dependent states (ADSs) in wiretap channel is revisited. The transmitter aims to convey a confidential message to the receiver and protect it from the wiretapper as possible as he can. Actions are taken by the transmitter to influence the channel state information. For such a channel, Dai et al. first got an outer bound on the capacity-equivocation region which contains all the achievable transmission rates. We find a new outer bound and prove it is better than Dai's in terms of approximating the maximum rate at which the confidential message can be transmitted in perfect secrecy. Furthermore, the new outer bound provides the engineer with a more precise target to achieve higher transmission rates in the capacity-equivocation region.

International Conference on Mechatronic Science, Electric Engineering and ComputerDec 1, 20130 citations

Wiretap Channel with Information Embedding on Actions

Xinxing Yin, Zhi Xue

Information embedding on actions is a new channel model in which a specific decoder is used to observe the actions taken by the encoder and retrieve part of the message intended for the receiver. We revisit this model and consider a different scenario where a secrecy constraint is imposed. By adding a wiretapper in the model, we aim to send the confidential message to the receiver and keep it secret from the wiretapper as much as possible. We characterize the inner and outer bounds on the capacity-equivocation region of such a channel with noncausal (and causal) channel state information. Furthermore, the lower and upper bounds on the sum secrecy capacity are also obtained. Besides, by eliminating the specific decoder, we get a new outer bound on the capacity-equivocation region of the wiretap channel with action-dependent states and prove it is tighter than the existing outer bound. A binary example is presented to illustrate the tradeoff between the sum secrecy rate and the information embedding rate under the secrecy constraint. We find that the secrecy constraint and the communication requirements of information embedding have a negative impact on improving the secrecy transmission rate of the given communication link.

EntropyApr 14, 20144 citations