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arXiv · 0908.0390

Byzantine Convergence in Robots Networks: The Price of Asynchrony

Zohir Bouzid·Maria Potop-Butucaru·Sébastien Tixeuil
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Abstract

We study the convergence problem in fully asynchronous, uni-dimensional robot networks that are prone to Byzantine (i.e. malicious) failures. In these settings, oblivious anonymous robots with arbitrary initial positions are required to eventually converge to an a apriori unknown position despite a subset of them exhibiting Byzantine behavior. Our contribution is twofold. We propose a deterministic algorithm that solves the problem in the most generic settings: fully asynchronous robots that operate in the non-atomic CORDA model. Our algorithm provides convergence in 5f+1-sized networks where f is the upper bound on the number of Byzantine robots. Additionally, we prove that 5f+1 is a lower bound whenever robot scheduling is fully asynchronous. This constrasts with previous results in partially synchronous robots networks, where 3f+1 robots are necessary and sufficient.

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Zohir Bouzid, Maria Potop-Butucaru, Sébastien Tixeuil. 2009-08-04. Byzantine Convergence in Robots Networks: The Price of Asynchrony. https://arxiv.org/abs/0908.0390

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