On Key Evolution over Wireless Channels

Zhihong Liu,Pingjuan Zhang,Yong Zeng,Qiping Huang

doi:10.1155/2015/592848

Zhihong Liu, Pingjuan Zhang + Show 2 more

Open Access

https://doi.org/10.1155/2015/592848

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Abstract

Noise is a powerful resource for the implementation of cryptographic primitives, especially in wireless networks. In general, a key agreement protocol is tailored to the channels and relies on the assumption that knowledge on the eavesdropper's channel is available. This is not practical. In this paper, we focus on the problem of developing key agreement schemes for secure communication across wireless channels and propose a key evolution scheme to alleviate the assumption. Keys evolve continuously based on the transmitted messages over the noisy wireless channel. Even if the eavesdropper's channel is superior to the legitimate receiver, the legitimate parties can establish secret keys. To further confuse the eavesdropper, we present a strategy for legitimate parties to send artificial noise if the eavesdropper cannot distinguish the sources of messages. Finally, we propose a k-resistant encryption scheme that can use different keys to encrypt and decrypt messages if there are no more than k bits which differ between the encryption and decryption keys.

Highlights

Security in wireless channels is regarded as an independent feature addressed above the physical layer, and all widely used cryptographic protocols are designed and implemented assuming the physical layer has already been established
The basic principle of information theoretic security calls for the combination of cryptographic scheme with channel coding techniques that exploit the randomness of communication channels to guarantee that the messages sent cannot be decoded by a third party maliciously eavesdropping on the wireless channel
The honest parties Alice and Bob are separated by a channel called the main channel; any eavesdropper Eve observes information transmitted by Alice through another channel called the wiretapper’s channel

Summary

Introduction

Security in wireless channels is regarded as an independent feature addressed above the physical layer, and all widely used cryptographic protocols are designed and implemented assuming the physical layer has already been established. The basic principle of information theoretic security calls for the combination of cryptographic scheme with channel coding techniques that exploit the randomness of communication channels to guarantee that the messages sent cannot be decoded by a third party maliciously eavesdropping on the wireless channel. If a pair of keys only has at most k-bit different, the receiver can recover the message; otherwise, he obtains no information about the message In this setting, a k-RES can be viewed as a conceptual wiretap channel that has a main channel and a worse wiretap channel. To secure the communication between sensors, they can use key evolution scheme to obtain a relatively secret key and refresh it as quickly as possible

Preliminaries

Key Evolution

Artificial Noise to Confuse Adversaries

Conclusions