dc.contributor.author Silva, Douglas Simões dc.contributor.author Graczyk, Rafal dc.contributor.author Decouchant, Jérémie dc.contributor.author Völp, Marcus dc.contributor.author Esteves-Verissimo, Paulo dc.date.accessioned 2021-11-23T12:22:40Z dc.date.available 2021-11-23T12:22:40Z dc.date.issued 2021-11-22 dc.identifier.citation Silva, D. S., Graczyk, R., Decouchant, J., Volp, M., & Esteves-Verissimo, P. (2021). Threat Adaptive Byzantine Fault Tolerant State-Machine Replication. 2021 40th International Symposium on Reliable Distributed Systems (SRDS). doi:10.1109/srds53918.2021.00017 dc.identifier.isbn 978-1-6654-3820-9 dc.identifier.issn 1060-9857 dc.identifier.doi 10.1109/SRDS53918.2021.00017 dc.identifier.uri http://hdl.handle.net/10754/673736 dc.description.abstract Critical infrastructures have to withstand advanced and persistent threats, which can be addressed using Byzantine fault tolerant state-machine replication (BFT-SMR). In practice, unattended cyberdefense systems rely on threat level detectors that synchronously inform them of changing threat levels. However, to have a BFT-SMR protocol operate unattended, the state-of-the-art is still to configure them to withstand the highest possible number of faulty replicas $f$ they might encounter, which limits their performance, or to make the strong assumption that a trusted external reconfiguration service is available, which introduces a single point of failure. In this work, we present ThreatAdaptive the first BFT-SMR protocol that is automatically strengthened or optimized by its replicas in reaction to threat level changes. We first determine under which conditions replicas can safely reconfigure a BFT-SMR system, i.e., adapt the number of replicas $n$ and the fault threshold $f$ so as to outpace an adversary. Since replicas typically communicate with each other using an asynchronous network they cannot rely on consensus to decide how the system should be reconfigured. ThreatAdaptive avoids this pitfall by proactively preparing the reconfiguration that may be triggered by an increasing threat when it optimizes its performance. Our evaluation shows that ThreatAdaptive can meet the latency and throughput of BFT baselines configured statically for a particular level of threat, and adapt 30% faster than previous methods, which make stronger assumptions to provide safety. dc.description.sponsorship This work is partially funded by FNR through Pearl grant IISD and the Core project ThreatAdapt C18/IS/1269492 dc.publisher IEEE dc.relation.url https://ieeexplore.ieee.org/document/9603657/ dc.relation.url https://ieeexplore.ieee.org/document/9603657/ dc.relation.url https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9603657 dc.rights Archived with thanks to IEEE dc.subject Threat adaptive systems dc.subject Byzantine fault tolerant state machine replication dc.subject Resilient computing dc.title Threat Adaptive Byzantine Fault Tolerant State-Machine Replication dc.type Conference Paper dc.contributor.department RC3 - KAUST dc.conference.date 20-23 Sept. 2021 dc.conference.name 2021 40th International Symposium on Reliable Distributed Systems (SRDS) dc.conference.location Chicago, IL, USA dc.eprint.version Post-print dc.contributor.institution SnT - University of Luxembourg dc.contributor.institution Delft University of Technology kaust.person Esteves-Verissimo, Paulo dc.date.published-online 2021-11-22 dc.date.published-print 2021-09
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