[{"oa_version":"Published Version","project":[{"_id":"34a4ce89-11ca-11ed-8bc3-8cc37fb6e11f","grant_number":"F8512","name":"Secure Network and Hardware for Efficient Blockchains"}],"month":"08","publication":"32nd USENIX Security Symposium","has_accepted_license":"1","conference":{"start_date":"2023-08-09","name":"USENIX Security Symposium","end_date":"2023-08-11","location":"Anaheim, CA, United States"},"language":[{"iso":"eng"}],"publication_identifier":{"isbn":["9781713879497"]},"oa":1,"date_published":"2023-08-15T00:00:00Z","type":"conference","file":[{"success":1,"relation":"main_file","access_level":"open_access","file_id":"14621","creator":"dernst","date_created":"2023-11-28T09:14:34Z","file_size":704331,"checksum":"1a730765930138e23c6efd2575872641","date_updated":"2023-11-28T09:14:34Z","content_type":"application/pdf","file_name":"2023_USENIX_Das.pdf"}],"main_file_link":[{"url":"https://eprint.iacr.org/2022/1389","open_access":"1"}],"status":"public","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication_status":"published","department":[{"_id":"ElKo"}],"article_processing_charge":"No","date_created":"2023-11-26T23:00:55Z","title":"Practical asynchronous high-threshold distributed key generation and distributed polynomial sampling","intvolume":"         8","_id":"14609","scopus_import":"1","author":[{"last_name":"Das","first_name":"Sourav","full_name":"Das, Sourav"},{"first_name":"Zhuolun","last_name":"Xiang","full_name":"Xiang, Zhuolun"},{"full_name":"Kokoris Kogias, Eleftherios","last_name":"Kokoris Kogias","first_name":"Eleftherios","id":"f5983044-d7ef-11ea-ac6d-fd1430a26d30"},{"first_name":"Ling","last_name":"Ren","full_name":"Ren, Ling"}],"publisher":"Usenix","page":"5359-5376","quality_controlled":"1","file_date_updated":"2023-11-28T09:14:34Z","day":"15","abstract":[{"text":"Distributed Key Generation (DKG) is a technique to bootstrap threshold cryptosystems without a trusted party. DKG is an essential building block to many decentralized protocols such as randomness beacons, threshold signatures, Byzantine consensus, and multiparty computation. While significant progress has been made recently, existing asynchronous DKG constructions are inefficient when the reconstruction threshold is larger than one-third of the total nodes. In this paper, we present a simple and concretely efficient asynchronous DKG (ADKG) protocol among n = 3t + 1 nodes that can tolerate up to t malicious nodes and support any reconstruction threshold ℓ ≥ t. Our protocol has an expected O(κn3) communication cost, where κ is the security parameter, and only assumes the hardness of the Discrete Logarithm. The\r\ncore ingredient of our ADKG protocol is an asynchronous protocol to secret share a random polynomial of degree ℓ ≥ t, which has other applications, such as asynchronous proactive secret sharing and asynchronous multiparty computation. We implement our high-threshold ADKG protocol and evaluate it using a network of up to 128 geographically distributed nodes. Our evaluation shows that our high-threshold ADKG protocol reduces the running time by 90% and bandwidth usage by 80% over the state-of-the-art.","lang":"eng"}],"date_updated":"2023-11-28T09:17:38Z","citation":{"ieee":"S. Das, Z. Xiang, E. Kokoris Kogias, and L. Ren, “Practical asynchronous high-threshold distributed key generation and distributed polynomial sampling,” in <i>32nd USENIX Security Symposium</i>, Anaheim, CA, United States, 2023, vol. 8, pp. 5359–5376.","chicago":"Das, Sourav, Zhuolun Xiang, Eleftherios Kokoris Kogias, and Ling Ren. “Practical Asynchronous High-Threshold Distributed Key Generation and Distributed Polynomial Sampling.” In <i>32nd USENIX Security Symposium</i>, 8:5359–76. Usenix, 2023.","ama":"Das S, Xiang Z, Kokoris Kogias E, Ren L. Practical asynchronous high-threshold distributed key generation and distributed polynomial sampling. In: <i>32nd USENIX Security Symposium</i>. Vol 8. Usenix; 2023:5359-5376.","apa":"Das, S., Xiang, Z., Kokoris Kogias, E., &#38; Ren, L. (2023). Practical asynchronous high-threshold distributed key generation and distributed polynomial sampling. In <i>32nd USENIX Security Symposium</i> (Vol. 8, pp. 5359–5376). Anaheim, CA, United States: Usenix.","ista":"Das S, Xiang Z, Kokoris Kogias E, Ren L. 2023. Practical asynchronous high-threshold distributed key generation and distributed polynomial sampling. 32nd USENIX Security Symposium. USENIX Security Symposium vol. 8, 5359–5376.","short":"S. Das, Z. Xiang, E. Kokoris Kogias, L. Ren, in:, 32nd USENIX Security Symposium, Usenix, 2023, pp. 5359–5376.","mla":"Das, Sourav, et al. “Practical Asynchronous High-Threshold Distributed Key Generation and Distributed Polynomial Sampling.” <i>32nd USENIX Security Symposium</i>, vol. 8, Usenix, 2023, pp. 5359–76."},"year":"2023","volume":8,"acknowledgement":"The authors would like to thank Amit Agarwal, Andrew Miller, and Tom Yurek for the helpful discussions related to the paper. This work is funded in part by a VMware early career faculty grant, a Chainlink Labs Ph.D. fellowship, the National Science Foundation, and the Austrian Science Fund (FWF) F8512-N.","ddc":["000"]},{"author":[{"first_name":"Christos","last_name":"Stefo","full_name":"Stefo, Christos","id":"a20e8902-32b0-11ee-9fa8-b23fa638b793"},{"full_name":"Xiang, Zhuolun","first_name":"Zhuolun","last_name":"Xiang"},{"last_name":"Kokoris Kogias","first_name":"Eleftherios","full_name":"Kokoris Kogias, Eleftherios","id":"f5983044-d7ef-11ea-ac6d-fd1430a26d30"}],"_id":"14735","scopus_import":"1","alternative_title":["LNCS"],"title":"Executing and proving over dirty ledgers","intvolume":"     13950","publication_status":"published","department":[{"_id":"ElKo"},{"_id":"GradSch"}],"date_created":"2024-01-08T09:17:38Z","article_processing_charge":"No","page":"3-20","quality_controlled":"1","publisher":"Springer Nature","date_updated":"2024-01-08T09:28:14Z","citation":{"ista":"Stefo C, Xiang Z, Kokoris Kogias E. 2023. Executing and proving over dirty ledgers. 27th International Conference on Financial Cryptography and Data Security. FC: Financial Cryptography and Data Security, LNCS, vol. 13950, 3–20.","short":"C. Stefo, Z. Xiang, E. Kokoris Kogias, in:, 27th International Conference on Financial Cryptography and Data Security, Springer Nature, 2023, pp. 3–20.","mla":"Stefo, Christos, et al. “Executing and Proving over Dirty Ledgers.” <i>27th International Conference on Financial Cryptography and Data Security</i>, vol. 13950, Springer Nature, 2023, pp. 3–20, doi:<a href=\"https://doi.org/10.1007/978-3-031-47754-6_1\">10.1007/978-3-031-47754-6_1</a>.","ieee":"C. Stefo, Z. Xiang, and E. Kokoris Kogias, “Executing and proving over dirty ledgers,” in <i>27th International Conference on Financial Cryptography and Data Security</i>, Bol, Brac, Croatia, 2023, vol. 13950, pp. 3–20.","chicago":"Stefo, Christos, Zhuolun Xiang, and Eleftherios Kokoris Kogias. “Executing and Proving over Dirty Ledgers.” In <i>27th International Conference on Financial Cryptography and Data Security</i>, 13950:3–20. Springer Nature, 2023. <a href=\"https://doi.org/10.1007/978-3-031-47754-6_1\">https://doi.org/10.1007/978-3-031-47754-6_1</a>.","ama":"Stefo C, Xiang Z, Kokoris Kogias E. Executing and proving over dirty ledgers. In: <i>27th International Conference on Financial Cryptography and Data Security</i>. Vol 13950. Springer Nature; 2023:3-20. doi:<a href=\"https://doi.org/10.1007/978-3-031-47754-6_1\">10.1007/978-3-031-47754-6_1</a>","apa":"Stefo, C., Xiang, Z., &#38; Kokoris Kogias, E. (2023). Executing and proving over dirty ledgers. In <i>27th International Conference on Financial Cryptography and Data Security</i> (Vol. 13950, pp. 3–20). Bol, Brac, Croatia: Springer Nature. <a href=\"https://doi.org/10.1007/978-3-031-47754-6_1\">https://doi.org/10.1007/978-3-031-47754-6_1</a>"},"year":"2023","abstract":[{"text":"Scaling blockchain protocols to perform on par with the expected needs of Web3.0 has been proven to be a challenging task with almost a decade of research. In the forefront of the current solution is the idea of separating the execution of the updates encoded in a block from the ordering of blocks. In order to achieve this, a new class of protocols called rollups has emerged. Rollups have as input a total ordering of valid and invalid transactions and as output a new valid state-transition.\r\nIf we study rollups from a distributed computing perspective, we uncover that rollups take as input the output of a Byzantine Atomic Broadcast (BAB) protocol and convert it to a State Machine Replication (SMR) protocol. BAB and SMR, however, are considered equivalent as far as distributed computing is concerned and a solution to one can easily be retrofitted to solve the other simply by adding/removing an execution step before the validation of the input.\r\nThis “easy” step of retrofitting an atomic broadcast solution to implement an SMR has, however, been overlooked in practice. In this paper, we formalize the problem and show that after BAB is solved, traditional impossibility results for consensus no longer apply towards an SMR. Leveraging this we propose a distributed execution protocol that allows reduced execution and storage cost per executor (O(log2n/n)) without relaxing the network assumptions of the underlying BAB protocol and providing censorship-resistance. Finally, we propose efficient non-interactive light client constructions that leverage our efficient execution protocols and do not require any synchrony assumptions or expensive ZK-proofs.","lang":"eng"}],"doi":"10.1007/978-3-031-47754-6_1","day":"01","volume":13950,"acknowledgement":"Eleftherios Kokoris-Kogias is partially supported by Austrian Science Fund (FWF) grant No: F8512-N.","publication":"27th International Conference on Financial Cryptography and Data Security","month":"12","oa_version":"Preprint","project":[{"_id":"34a4ce89-11ca-11ed-8bc3-8cc37fb6e11f","name":"Secure Network and Hardware for Efficient Blockchains","grant_number":"F8512"}],"language":[{"iso":"eng"}],"conference":{"end_date":"2023-05-05","location":"Bol, Brac, Croatia","start_date":"2023-05-01","name":"FC: Financial Cryptography and Data Security"},"date_published":"2023-12-01T00:00:00Z","type":"conference","oa":1,"publication_identifier":{"issn":["1611-3349"],"eissn":["0302-9743"],"eisbn":["9783031477546"],"isbn":["9783031477539"]},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","status":"public","main_file_link":[{"url":"https://eprint.iacr.org/2022/1554","open_access":"1"}]},{"publication":"27th International Conference on Financial Cryptography and Data Security","month":"12","project":[{"_id":"34a4ce89-11ca-11ed-8bc3-8cc37fb6e11f","grant_number":"F8512","name":"Secure Network and Hardware for Efficient Blockchains"}],"oa_version":"Submitted Version","language":[{"iso":"eng"}],"conference":{"end_date":"2023-05-05","location":"Bol, Brac, Croatia","start_date":"2023-05-01","name":"FC: Financial Cryptography and Data Security"},"type":"conference","date_published":"2023-12-01T00:00:00Z","oa":1,"publication_identifier":{"eisbn":["9783031477515"],"issn":["0302-9743"],"eissn":["1611-3349"],"isbn":["9783031477508"]},"status":"public","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","main_file_link":[{"open_access":"1","url":"https://fc23.ifca.ai/preproceedings/150.pdf"}],"author":[{"last_name":"Cohen","first_name":"Shir","full_name":"Cohen, Shir"},{"full_name":"Goren, Guy","last_name":"Goren","first_name":"Guy"},{"id":"f5983044-d7ef-11ea-ac6d-fd1430a26d30","last_name":"Kokoris Kogias","first_name":"Eleftherios","full_name":"Kokoris Kogias, Eleftherios"},{"last_name":"Sonnino","first_name":"Alberto","full_name":"Sonnino, Alberto"},{"full_name":"Spiegelman, Alexander","last_name":"Spiegelman","first_name":"Alexander"}],"scopus_import":"1","_id":"14829","intvolume":"     13951","title":"Proof of availability and retrieval in a modular blockchain architecture","alternative_title":["LNCS"],"article_processing_charge":"No","date_created":"2024-01-18T07:41:12Z","department":[{"_id":"ElKo"}],"publication_status":"published","quality_controlled":"1","page":"36-53","publisher":"Springer Nature","year":"2023","citation":{"mla":"Cohen, Shir, et al. “Proof of Availability and Retrieval in a Modular Blockchain Architecture.” <i>27th International Conference on Financial Cryptography and Data Security</i>, vol. 13951, Springer Nature, 2023, pp. 36–53, doi:<a href=\"https://doi.org/10.1007/978-3-031-47751-5_3\">10.1007/978-3-031-47751-5_3</a>.","short":"S. Cohen, G. Goren, E. Kokoris Kogias, A. Sonnino, A. Spiegelman, in:, 27th International Conference on Financial Cryptography and Data Security, Springer Nature, 2023, pp. 36–53.","ista":"Cohen S, Goren G, Kokoris Kogias E, Sonnino A, Spiegelman A. 2023. Proof of availability and retrieval in a modular blockchain architecture. 27th International Conference on Financial Cryptography and Data Security. FC: Financial Cryptography and Data Security, LNCS, vol. 13951, 36–53.","apa":"Cohen, S., Goren, G., Kokoris Kogias, E., Sonnino, A., &#38; Spiegelman, A. (2023). Proof of availability and retrieval in a modular blockchain architecture. In <i>27th International Conference on Financial Cryptography and Data Security</i> (Vol. 13951, pp. 36–53). Bol, Brac, Croatia: Springer Nature. <a href=\"https://doi.org/10.1007/978-3-031-47751-5_3\">https://doi.org/10.1007/978-3-031-47751-5_3</a>","ama":"Cohen S, Goren G, Kokoris Kogias E, Sonnino A, Spiegelman A. Proof of availability and retrieval in a modular blockchain architecture. In: <i>27th International Conference on Financial Cryptography and Data Security</i>. Vol 13951. Springer Nature; 2023:36-53. doi:<a href=\"https://doi.org/10.1007/978-3-031-47751-5_3\">10.1007/978-3-031-47751-5_3</a>","ieee":"S. Cohen, G. Goren, E. Kokoris Kogias, A. Sonnino, and A. Spiegelman, “Proof of availability and retrieval in a modular blockchain architecture,” in <i>27th International Conference on Financial Cryptography and Data Security</i>, Bol, Brac, Croatia, 2023, vol. 13951, pp. 36–53.","chicago":"Cohen, Shir, Guy Goren, Eleftherios Kokoris Kogias, Alberto Sonnino, and Alexander Spiegelman. “Proof of Availability and Retrieval in a Modular Blockchain Architecture.” In <i>27th International Conference on Financial Cryptography and Data Security</i>, 13951:36–53. Springer Nature, 2023. <a href=\"https://doi.org/10.1007/978-3-031-47751-5_3\">https://doi.org/10.1007/978-3-031-47751-5_3</a>."},"date_updated":"2024-01-22T13:58:07Z","abstract":[{"text":"This paper explores a modular design architecture aimed at helping blockchains (and other SMR implementation) to scale to a very large number of processes. This comes in contrast to existing monolithic architectures that interleave transaction dissemination, ordering, and execution in a single functionality. To achieve this we first split the monolith to multiple layers which can use existing distributed computing primitives. The exact specifications of the data dissemination part are formally defined by the Proof of Availability & Retrieval (PoA &R) abstraction. Solutions to the PoA &R problem contain two related sub-protocols: one that “pushes” information into the network and another that “pulls” this information. Regarding the latter, there is a dearth of research literature which is rectified in this paper. We present a family of pulling sub-protocols and rigorously analyze them. Extensive simulations support the theoretical claims of efficiency and robustness in case of a very large number of players. Finally, actual implementation and deployment on a small number of machines (roughly the size of several industrial systems) demonstrates the viability of the architecture’s paradigm.","lang":"eng"}],"day":"01","doi":"10.1007/978-3-031-47751-5_3","volume":13951,"acknowledgement":"This work is partially supported by Meta. Eleftherios Kokoris-Kogias is partially supported by Austrian Science Fund (FWF) grant No: F8512-N. Shir Cohen is supported by the Adams Fellowship Program of the Israel Academy of Sciences and Humanities."}]