[{"oa_version":"Preprint","date_updated":"2023-09-04T11:42:10Z","type":"conference","day":"21","article_processing_charge":"No","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","department":[{"_id":"ElKo"}],"doi":"10.1145/3465084.3467941","language":[{"iso":"eng"}],"external_id":{"isi":["000744439800018"],"arxiv":["2103.03181"]},"keyword":["optimal","state machine replication","fallback","asynchrony","byzantine faults"],"date_published":"2021-07-21T00:00:00Z","page":"187-190","arxiv":1,"scopus_import":"1","publication_identifier":{"isbn":["9-781-4503-8548-0"]},"year":"2021","main_file_link":[{"url":"https://arxiv.org/abs/2103.03181","open_access":"1"}],"citation":{"apa":"Gelashvili, R., Kokoris Kogias, E., Spiegelman, A., &#38; Xiang, Z. (2021). Brief announcement: Be prepared when network goes bad: An asynchronous view-change protocol. In <i>Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing</i> (pp. 187–190). Virtual, Italy: Association for Computing Machinery. <a href=\"https://doi.org/10.1145/3465084.3467941\">https://doi.org/10.1145/3465084.3467941</a>","mla":"Gelashvili, Rati, et al. “Brief Announcement: Be Prepared When Network Goes Bad: An Asynchronous View-Change Protocol.” <i>Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing</i>, Association for Computing Machinery, 2021, pp. 187–90, doi:<a href=\"https://doi.org/10.1145/3465084.3467941\">10.1145/3465084.3467941</a>.","ista":"Gelashvili R, Kokoris Kogias E, Spiegelman A, Xiang Z. 2021. Brief announcement: Be prepared when network goes bad: An asynchronous view-change protocol. Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing. PODC: Principles of Distributed Computing, 187–190.","chicago":"Gelashvili, Rati, Eleftherios Kokoris Kogias, Alexander Spiegelman, and Zhuolun Xiang. “Brief Announcement: Be Prepared When Network Goes Bad: An Asynchronous View-Change Protocol.” In <i>Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing</i>, 187–90. Association for Computing Machinery, 2021. <a href=\"https://doi.org/10.1145/3465084.3467941\">https://doi.org/10.1145/3465084.3467941</a>.","short":"R. Gelashvili, E. Kokoris Kogias, A. Spiegelman, Z. Xiang, in:, Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing, Association for Computing Machinery, 2021, pp. 187–190.","ieee":"R. Gelashvili, E. Kokoris Kogias, A. Spiegelman, and Z. Xiang, “Brief announcement: Be prepared when network goes bad: An asynchronous view-change protocol,” in <i>Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing</i>, Virtual, Italy, 2021, pp. 187–190.","ama":"Gelashvili R, Kokoris Kogias E, Spiegelman A, Xiang Z. Brief announcement: Be prepared when network goes bad: An asynchronous view-change protocol. In: <i>Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing</i>. Association for Computing Machinery; 2021:187-190. doi:<a href=\"https://doi.org/10.1145/3465084.3467941\">10.1145/3465084.3467941</a>"},"author":[{"full_name":"Gelashvili, Rati","first_name":"Rati","last_name":"Gelashvili"},{"full_name":"Kokoris Kogias, Eleftherios","id":"f5983044-d7ef-11ea-ac6d-fd1430a26d30","first_name":"Eleftherios","last_name":"Kokoris Kogias"},{"last_name":"Spiegelman","first_name":"Alexander","full_name":"Spiegelman, Alexander"},{"last_name":"Xiang","first_name":"Zhuolun","full_name":"Xiang, Zhuolun"}],"quality_controlled":"1","abstract":[{"lang":"eng","text":"The popularity of permissioned blockchain systems demands BFT SMR protocols that are efficient under good network conditions (synchrony) and robust under bad network conditions (asynchrony). The state-of-the-art partially synchronous BFT SMR protocols provide optimal linear communication cost per decision under synchrony and good leaders, but lose liveness under asynchrony. On the other hand, the state-of-the-art asynchronous BFT SMR protocols are live even under asynchrony, but always pay quadratic cost even under synchrony. In this paper, we propose a BFT SMR protocol that achieves the best of both worlds -- optimal linear cost per decision under good networks and leaders, optimal quadratic cost per decision under bad networks, and remains always live."}],"publication_status":"published","publication":"Proceedings of the 2021 ACM Symposium on Principles of Distributed Computing","title":"Brief announcement: Be prepared when network goes bad: An asynchronous view-change protocol","_id":"10553","oa":1,"publisher":"Association for Computing Machinery","conference":{"name":"PODC: Principles of Distributed Computing","end_date":"2021-07-30","location":"Virtual, Italy","start_date":"2021-07-26"},"month":"07","date_created":"2021-12-16T13:20:19Z","status":"public","isi":1},{"alternative_title":["LIPIcs"],"publication_identifier":{"eisbn":["978-3-95977-126-9"]},"scopus_import":1,"arxiv":1,"date_published":"2019-01-01T00:00:00Z","file":[{"date_updated":"2020-07-14T12:47:44Z","file_id":"6934","checksum":"2d2202f90c6ac991e50876451627c4b5","file_name":"LIPIcs-DISC-2019-29.pdf","access_level":"open_access","relation":"main_file","date_created":"2019-10-08T12:47:19Z","file_size":639378,"content_type":"application/pdf","creator":"jrybicki"}],"keyword":["consensus","approximate agreement","Byzantine faults","chordal graphs","lattice agreement"],"external_id":{"arxiv":["1908.02743"]},"page":"29:1--29:17","ec_funded":1,"doi":"10.4230/LIPICS.DISC.2019.29","language":[{"iso":"eng"}],"department":[{"_id":"DaAl"}],"has_accepted_license":"1","user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","article_processing_charge":"No","date_updated":"2021-01-12T08:09:38Z","type":"conference","oa_version":"Published Version","intvolume":"       146","date_created":"2019-10-08T12:41:38Z","conference":{"end_date":"2019-10-18","name":"DISC: International Symposium on Distributed Computing","location":"Budapest, Hungary","start_date":"2019-10-14"},"status":"public","volume":146,"file_date_updated":"2020-07-14T12:47:44Z","publisher":"Schloss Dagstuhl - Leibniz-Zentrum für Informatik","title":"Byzantine approximate agreement on graphs","publication":"33rd International Symposium on Distributed Computing","ddc":["004"],"oa":1,"_id":"6931","project":[{"_id":"260C2330-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"ISTplus - Postdoctoral Fellowships","grant_number":"754411"}],"publication_status":"published","abstract":[{"lang":"eng","text":"Consider a distributed system with n processors out of which f can be Byzantine faulty. In the\r\napproximate agreement task, each processor i receives an input value xi and has to decide on an\r\noutput value yi such that\r\n1. the output values are in the convex hull of the non-faulty processors’ input values,\r\n2. the output values are within distance d of each other.\r\n\r\n\r\nClassically, the values are assumed to be from an m-dimensional Euclidean space, where m ≥ 1.\r\nIn this work, we study the task in a discrete setting, where input values with some structure\r\nexpressible as a graph. Namely, the input values are vertices of a finite graph G and the goal is to\r\noutput vertices that are within distance d of each other in G, but still remain in the graph-induced\r\nconvex hull of the input values. For d = 0, the task reduces to consensus and cannot be solved with\r\na deterministic algorithm in an asynchronous system even with a single crash fault. For any d ≥ 1,\r\nwe show that the task is solvable in asynchronous systems when G is chordal and n > (ω + 1)f,\r\nwhere ω is the clique number of G. In addition, we give the first Byzantine-tolerant algorithm for a\r\nvariant of lattice agreement. For synchronous systems, we show tight resilience bounds for the exact\r\nvariants of these and related tasks over a large class of combinatorial structures."}],"citation":{"apa":"Nowak, T., &#38; Rybicki, J. (2019). Byzantine approximate agreement on graphs. In <i>33rd International Symposium on Distributed Computing</i> (Vol. 146, p. 29:1--29:17). Budapest, Hungary: Schloss Dagstuhl - Leibniz-Zentrum für Informatik. <a href=\"https://doi.org/10.4230/LIPICS.DISC.2019.29\">https://doi.org/10.4230/LIPICS.DISC.2019.29</a>","mla":"Nowak, Thomas, and Joel Rybicki. “Byzantine Approximate Agreement on Graphs.” <i>33rd International Symposium on Distributed Computing</i>, vol. 146, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019, p. 29:1--29:17, doi:<a href=\"https://doi.org/10.4230/LIPICS.DISC.2019.29\">10.4230/LIPICS.DISC.2019.29</a>.","ista":"Nowak T, Rybicki J. 2019. Byzantine approximate agreement on graphs. 33rd International Symposium on Distributed Computing. DISC: International Symposium on Distributed Computing, LIPIcs, vol. 146, 29:1--29:17.","chicago":"Nowak, Thomas, and Joel Rybicki. “Byzantine Approximate Agreement on Graphs.” In <i>33rd International Symposium on Distributed Computing</i>, 146:29:1--29:17. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019. <a href=\"https://doi.org/10.4230/LIPICS.DISC.2019.29\">https://doi.org/10.4230/LIPICS.DISC.2019.29</a>.","short":"T. Nowak, J. Rybicki, in:, 33rd International Symposium on Distributed Computing, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019, p. 29:1--29:17.","ama":"Nowak T, Rybicki J. Byzantine approximate agreement on graphs. In: <i>33rd International Symposium on Distributed Computing</i>. Vol 146. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2019:29:1--29:17. doi:<a href=\"https://doi.org/10.4230/LIPICS.DISC.2019.29\">10.4230/LIPICS.DISC.2019.29</a>","ieee":"T. Nowak and J. Rybicki, “Byzantine approximate agreement on graphs,” in <i>33rd International Symposium on Distributed Computing</i>, Budapest, Hungary, 2019, vol. 146, p. 29:1--29:17."},"quality_controlled":"1","author":[{"full_name":"Nowak, Thomas","last_name":"Nowak","first_name":"Thomas"},{"id":"334EFD2E-F248-11E8-B48F-1D18A9856A87","full_name":"Rybicki, Joel","orcid":"0000-0002-6432-6646","last_name":"Rybicki","first_name":"Joel"}],"tmp":{"image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"year":"2019"}]