Consensus in Networked Multi-Agent Systems with Adversaries

Authors: Heath LeBlanc, Xenofon Koutsoukos

Proceedings of the 14th international conference on Hybrid systems: computation and control (HSCC2011)

Abstract:

In the past decade, numerous consensus protocols for networked
multi-agent systems have been proposed. Although some forms of
robustness of these algorithms have been studied, reaching consensus
securely in networked multi-agent systems, in spite of intrusions
caused by malicious agents, or adversaries, has been largely
underexplored. In this work, we consider a general model for adversaries
in Euclidean space and introduce a consensus problem for
networked multi-agent systems similar to the Byzantine consensus
problem in distributed computing. We present the Adversarially
Robust Consensus Protocol (ARC-P), which combines ideas from
consensus algorithms that are resilient to Byzantine faults and from
linear consensus protocols used for control and coordination of dynamic
agents. We show that ARC-P solves the consensus problem
in complete networks whenever there are more cooperative agents
than adversaries. Finally, we illustrate the resilience of ARC-P to
adversaries through simulations and compare ARC-P with a linear
consensus protocol for networked multi-agent systems.