zkPAKE: A Simple Augmented PAKE Protocol

Abstract

Human memory is notoriously unreliable in memorizing long secrets, such as large cryptographic keys. Password-based Authenticated Key Exchange (PAKE) protocols securely establish a cryptographic key based only on the knowledge of a much shorter password. In this work, an augmented PAKE protocol is designed and proposed for secure banking applications, requiring the server to store only the image of the password under a one-way function. The protocol is more efficient than alternatives because it requires fewer public key operations and a lower communication overhead.