The wiretap channel with generalized feedback: Secure communication and key generation

Abstract

It is well-known that feedback does not increase the capacity of point-to-point memoryless channels, however, the advantage it poses to secure communications is not fully understood yet. In this work, an achievable scheme for the wiretap channel with generalized feedback is presented. This scheme employs the feedback signal to generate a secret key shared between the legitimate users, which is then used to encrypt the message to be sent. It is shown that the resulting achievable rate recovers previous results, thus it can be seen as a generalization and unification of several results in the field.