Achieving Optimal Breakdown for Byzantine Robust Gossip
- URL: http://arxiv.org/abs/2410.10418v1
- Date: Mon, 14 Oct 2024 12:10:52 GMT
- Title: Achieving Optimal Breakdown for Byzantine Robust Gossip
- Authors: Renaud Gaucher, Aymeric Dieuleveut, Hadrien Hendrikx,
- Abstract summary: This paper investigates Byzantine-resilient algorithms in a decentralized setting, where devices communicate directly with one another.
We introduce $mathrmCG+$, an algorithm at the intersection of $mathrmClippedGossip$ and $mathrmNNA$, two popular approaches for robust decentralized learning.
- Score: 15.69624587054777
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Distributed approaches have many computational benefits, but they are vulnerable to attacks from a subset of devices transmitting incorrect information. This paper investigates Byzantine-resilient algorithms in a decentralized setting, where devices communicate directly with one another. We investigate the notion of breakdown point, and show an upper bound on the number of adversaries that decentralized algorithms can tolerate. We introduce $\mathrm{CG}^+$, an algorithm at the intersection of $\mathrm{ClippedGossip}$ and $\mathrm{NNA}$, two popular approaches for robust decentralized learning. $\mathrm{CG}^+$ meets our upper bound, and thus obtains optimal robustness guarantees, whereas neither of the existing two does. We provide experimental evidence for this gap by presenting an attack tailored to sparse graphs which breaks $\mathrm{NNA}$ but against which $\mathrm{CG}^+$ is robust.
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