Efficient Key Exchange for Wireless Multi-hop Networks

László Czap, Christina Fragouli, Iris Safaka
2015
Rapport ou document de travail

Résumé

We present a protocol that enables to create pairwise keys between nodes in a wireless network, so that the keys are secure from an adversary, Eve, with unbounded computational and memory capabilities, but with limited network presence. Our proposed protocol works over arbitrary multi-hop networks, unlike previously proposed protocols that only work when nodes are restricted to be within the same broadcast domain. Multi-hop networks enable to support a wider range of applications; we are inspired in this paper by a traffic-anonymization application. Multi-hop networks are also more interesting technically, as they offer a much richer palette of opportunities for secrecy, that include the inherently noisy nature of wireless, the existence of multiple paths between the network nodes, and interference from concurrent transmissions. We propose a protocol that leverages these opportunities, and show that it can create keys at a rate of tens of Kbps.

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https://infoscience.epfl.ch/record/207888?ln=fr

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, ,

We present protocols for creating pairwise secrets between nodes in a wireless network, so that these secrets are secure from an eavesdropper, Eve, with unbounded computational and memory capabilities, but with limited network presence. We first present a basic secret-agreement protocol for single-hop networks, where secrets are constructed using traffic exchanged between the nodes, and we show that, under standard theoretical assumptions, our protocol is information-theoretically secure. Second, we propose a secret-agreement protocol for arbitrary, multi-hop networks, that builds on the basic protocol but also comprises design features for leveraging additional sources, that multi-hop offers, for secrecy. Finally, we evaluate our protocols and we provide experimental evidence that it is feasible to create thousands of secret bits per second, in realistic wireless setups, the security of which is independent of Eve’s computational capabilities.

Ieee-Inst Electrical Electronics Engineers Inc2016

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2004