{"ddc":["000"],"author":[{"orcid":"0000-0002-9139-1654","id":"3E04A7AA-F248-11E8-B48F-1D18A9856A87","first_name":"Krzysztof Z","full_name":"Pietrzak, Krzysztof Z","last_name":"Pietrzak"}],"article_number":"60","type":"conference","year":"2019","date_created":"2019-06-06T14:12:36Z","volume":124,"date_updated":"2021-01-12T08:07:53Z","month":"01","_id":"6528","title":"Simple verifiable delay functions","department":[{"_id":"KrPi"}],"file":[{"file_size":558770,"checksum":"f0ae1bb161431d9db3dea5ace082bfb5","access_level":"open_access","file_id":"6529","relation":"main_file","file_name":"2019_LIPIcs_Pietrzak.pdf","date_created":"2019-06-06T14:22:04Z","content_type":"application/pdf","date_updated":"2020-07-14T12:47:33Z","creator":"dernst"}],"intvolume":"       124","has_accepted_license":"1","oa":1,"oa_version":"Published Version","publication_status":"published","tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png"},"date_published":"2019-01-10T00:00:00Z","publication_identifier":{"issn":["1868-8969"],"isbn":["978-3-95977-095-8"]},"main_file_link":[{"url":"https://eprint.iacr.org/2018/627","open_access":"1"}],"project":[{"_id":"258AA5B2-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"Teaching Old Crypto New Tricks","grant_number":"682815"}],"ec_funded":1,"status":"public","day":"10","publication":"10th Innovations in Theoretical Computer Science Conference","alternative_title":["LIPIcs"],"quality_controlled":"1","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","file_date_updated":"2020-07-14T12:47:33Z","abstract":[{"text":"We construct a verifiable delay function (VDF) by showing how the Rivest-Shamir-Wagner time-lock puzzle can be made publicly verifiable. Concretely, we give a statistically sound public-coin protocol to prove that a tuple (N,x,T,y) satisfies y=x2T (mod N) where the prover doesn’t know the factorization of N and its running time is dominated by solving the puzzle, that is, compute x2T, which is conjectured to require T sequential squarings. To get a VDF we make this protocol non-interactive using the Fiat-Shamir heuristic.The motivation for this work comes from the Chia blockchain design, which uses a VDF as akey ingredient. For typical parameters (T≤2 40, N= 2048), our proofs are of size around 10K B, verification cost around three RSA exponentiations and computing the proof is 8000 times faster than solving the puzzle even without any parallelism.","lang":"eng"}],"publisher":"Schloss Dagstuhl - Leibniz-Zentrum für Informatik","language":[{"iso":"eng"}],"article_processing_charge":"No","citation":{"chicago":"Pietrzak, Krzysztof Z. “Simple Verifiable Delay Functions.” In <i>10th Innovations in Theoretical Computer Science Conference</i>, Vol. 124. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019. <a href=\"https://doi.org/10.4230/LIPICS.ITCS.2019.60\">https://doi.org/10.4230/LIPICS.ITCS.2019.60</a>.","ama":"Pietrzak KZ. Simple verifiable delay functions. In: <i>10th Innovations in Theoretical Computer Science Conference</i>. Vol 124. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2019. doi:<a href=\"https://doi.org/10.4230/LIPICS.ITCS.2019.60\">10.4230/LIPICS.ITCS.2019.60</a>","ieee":"K. Z. Pietrzak, “Simple verifiable delay functions,” in <i>10th Innovations in Theoretical Computer Science Conference</i>, San Diego, CA, United States, 2019, vol. 124.","ista":"Pietrzak KZ. 2019. Simple verifiable delay functions. 10th Innovations in Theoretical Computer Science Conference. ITCS 2019: Innovations in Theoretical Computer Science, LIPIcs, vol. 124, 60.","mla":"Pietrzak, Krzysztof Z. “Simple Verifiable Delay Functions.” <i>10th Innovations in Theoretical Computer Science Conference</i>, vol. 124, 60, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019, doi:<a href=\"https://doi.org/10.4230/LIPICS.ITCS.2019.60\">10.4230/LIPICS.ITCS.2019.60</a>.","apa":"Pietrzak, K. Z. (2019). Simple verifiable delay functions. In <i>10th Innovations in Theoretical Computer Science Conference</i> (Vol. 124). San Diego, CA, United States: Schloss Dagstuhl - Leibniz-Zentrum für Informatik. <a href=\"https://doi.org/10.4230/LIPICS.ITCS.2019.60\">https://doi.org/10.4230/LIPICS.ITCS.2019.60</a>","short":"K.Z. Pietrzak, in:, 10th Innovations in Theoretical Computer Science Conference, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019."},"conference":{"location":"San Diego, CA, United States","end_date":"2019-01-12","name":"ITCS 2019: Innovations in Theoretical Computer Science","start_date":"2019-01-10"},"scopus_import":1,"doi":"10.4230/LIPICS.ITCS.2019.60"}