Revisiting Shamir's No-key Protocol: Lightweight Key Transport

Abstract

Key-transport protocols, subclasses of key-establishment protocols, are employed to convey secret keys from a principal to another for establishing a security association. In this paper, we propose a lightweight, practicable, tweakable, energy-efficient, and secure key-transport protocol, suitable for wireless sensor networks (WSN), Internet of Things (IoT) and mobile networks. The proposed protocol is based on the Shamir's no-key protocol. Although Shamir's no-key protocol does not require any pre-shared secret between principals, we show that it is impossible to employ the no-key protocol over public commutative groups. We modify Diffie-Hellman key-agreement protocol to morph it into a key-transport protocol by applying a set of changes on the original protocol and it becomes possible to compare both protocols in terms of memory usage and total time to accomplish a single key transport. The experimental results show that the proposed key transport protocol perform faster than the modified Diffie-Hellman protocol, and the total time to transport a single key by using the modified Diffie-Hellman protocol grows drastically with the increase in key size.