A Novel Physical Layer Secure Key Generation and Refreshment Scheme for Wireless Sensor Networks

Kemedi Moara-Nkwe,Mahmoud Hashem Eiza,Gyu Myoung Lee,Qi Shi

doi:10.1109/access.2018.2806423

Abstract

Physical layer secure key generation (PL-SKG) schemes have received a lot of attention from the wireless security community in recent years because of the potential benefits that they could bring to the security landscape. These schemes aim to strengthen current security protocols by reducing the amount of key material that devices need for deployment. They do this by harnessing the common source of randomness provided by the wireless channel that the physical layer is communicating over. This is of particular importance in wireless sensor networks (WSNs) where resources are particularly scarce and where issues, such as key revocation and recovery make the design of efficient key management schemes extremely difficult. This paper discusses the issues and challenges encountered in the design and implementation of PL-SKG schemes on off-the-shelf WSNs. It then proposes a novel key generation scheme that takes advantage of both the power and simplicity of classic error correcting codes and also the diversity of frequency channels available on 802.15.4 compliant nodes to generate keys from received signal strength readings. This paper shows that our key generation and refreshment scheme can achieve a near 100% key reconciliation rate whilst also providing perfect forward and backward security.

Highlights

Wireless Sensor Networks (WSNs) have grown in popularity over the last few decades because of their relatively low cost and their ease of deployment but such networks pose significant design challenges because of their limited computational prowess and their short battery life [1], [2]
Elliptic curve cryptography (ECC) based schemes implemented on WSN nodes such as TinyECC [3] will, for example, consume significant energy resources and even a single operation will still take a long time to compute [4]
Motivated by the above limitations, this paper proposes a new lightweight Physical Layer Secure Key Generation (PL-SKG) protocol for static networks, which uses Error Correcting Codes (ECCs) to reconcile keys in a secure manner that does not involve leaking any information about the formulated keys

Summary

INTRODUCTION

Wireless Sensor Networks (WSNs) have grown in popularity over the last few decades because of their relatively low cost and their ease of deployment but such networks pose significant design challenges because of their limited computational prowess and their short battery life [1], [2]. Physical Layer Secure Key Generation (PL-SKG) schemes aim to address the challenges highlighted above by enabling a key to be generated and refreshed in a relatively lightweight manner [5], [6] They achieve this feat by exploiting the diversity and inherent randomness of the wireless channel that the physical layer is communicating over to generate keys. The scheme uses ECCs to carry out the key reconciliation process and in so doing not revealing anything about the structure of the RSS samples This provides an improvement on current WSN PL-SKG schemes as no information that characterises the RSS samples accumulated by legitimate parties during the randomness sharing phase needs to exchanged in the key reconciliation phase.

RELATED WORK

SOURCES OF CHANNEL FADING IN WSNS

Result

RANDOMNESS TESTING

Findings

CONCLUSION AND FURTHER WORK