2026-07-23T22:33:23Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:11816 2024-03-06T10:48:51Z ddc:004 open_access

Exact Byzantine Consensus on Arbitrary Directed Graphs Under Local Broadcast Model Khan, Muhammad Samir Tseng, Lewis Vaidya, Nitin H. complexity and impossibility results for distributed computing fault-tolerance reliability We consider Byzantine consensus in a synchronous system where nodes are connected by a network modeled as a directed graph, i.e., communication links between neighboring nodes are not necessarily bi-directional. The directed graph model is motivated by wireless networks wherein asymmetric communication links can occur. In the classical point-to-point communication model, a message sent on a communication link is private between the two nodes on the link. This allows a Byzantine faulty node to equivocate, i.e., send inconsistent information to its neighbors. This paper considers the local broadcast model of communication, wherein transmission by a node is received identically by all of its outgoing neighbors, effectively depriving the faulty nodes of the ability to equivocate. Prior work has obtained sufficient and necessary conditions on undirected graphs to be able to achieve Byzantine consensus under the local broadcast model. In this paper, we obtain tight conditions on directed graphs to be able to achieve Byzantine consensus with binary inputs under the local broadcast model. The results obtained in the paper provide insights into the trade-off between directionality of communication links and the ability to achieve consensus. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Muhammad Samir Khan and Lewis Tseng and Nitin H. Vaidya 2020 Is Part Of LIPIcs, Volume 153, 23rd International Conference on Principles of Distributed Systems (OPODIS 2019) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.OPODIS.2019.30 urn:nbn:de:0030-drops-118161 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2019.30 eng https://creativecommons.org/licenses/by/3.0/legalcode