On Message Authentication Channel Capacity Over a Wiretap Channel

In this paper, a novel message authentication model using the same key over wiretap channel is proposed to achieve information-theoretic security. Specifically, in the proposed model, there is a discrete memoryless channel W-1 : x -> y between transmitter Alice and receiver Bob, while an attacker Oscar is connected with Alice via discrete memoryless channel W-2 : x -> z. Alice encodes message M to codeword (S, X-n), using an encoding function with secret key K. Then, S is sent to Bob over a one-way noiseless channel (fully controlled by Oscar), and X-n is sent over the wiretap channel, say X -> (Y, Z). Building on this model, a new message authentication scheme is proposed. The scheme incorporates a secure channel coding, which uses random coding techniques to detect man-in-the-middle (MITM) attacks. The authentication channel capacity is studied in a specific channel model when W-2 is not less noisy than W-1. We theoretically demonstrate that the authentication channel capacity is much larger than the secrecy capacity, since Bob does not need to recover information transmitted over the noisy channel.

Automated summary

In this paper, a novel message authentication model using the same key over wiretap channel is proposed to achieve information-theoretic security. The model consists of two discrete memoryless channels: one between transmitter Alice and receiver Bob, and another connecting attacker Oscar and Alice. Based on this model, a new message authentication scheme is proposed, which utilizes random coding techniques to detect man-in-the-middle attacks.