conference paper published yes Shir Cohen author Rati Gelashvili author Eleftherios Kokoris Kogias author f5983044-d7ef-11ea-ac6d-fd1430a26d30 Zekun Li author Dahlia Malkhi author Alberto Sonnino author Alexander Spiegelman author ElKo department FC: Financial Cryptography and Data Security Advances in blockchains have influenced the State-Machine-Replication (SMR) world and many state-of-the-art blockchain-SMR solutions are based on two pillars: Chaining and Leader-rotation. A predetermined round-robin mechanism used for Leader-rotation, however, has an undesirable behavior: crashed parties become designated leaders infinitely often, slowing down overall system performance. In this paper, we provide a new Leader-Aware SMR framework that, among other desirable properties, formalizes a Leader-utilization requirement that bounds the number of rounds whose leaders are faulty in crash-only executions. We introduce Carousel, a novel, reputation-based Leader-rotation solution to achieve Leader-Aware SMR. The challenge in adaptive Leader-rotation is that it cannot rely on consensus to determine a leader, since consensus itself needs a leader. Carousel uses the available on-chain information to determine a leader locally and achieves Liveness despite this difficulty. A HotStuff implementation fitted with Carousel demonstrates drastic performance improvements: it increases throughput over 2x in faultless settings and provided a 20x throughput increase and 5x latency reduction in the presence of faults. Springer Nature2022Grenada eng 0302-9743 1611-3349 9783031182822 2110.00960 00142364020001310.1007/978-3-031-18283-9_13 13411279-295 Cohen S, Gelashvili R, Kokoris Kogias E, Li Z, Malkhi D, Sonnino A, Spiegelman A. 2022. Be aware of your leaders. International Conference on Financial Cryptography and Data Security. FC: Financial Cryptography and Data Security, LNCS, vol. 13411, 279–295. S. Cohen, R. Gelashvili, E. Kokoris Kogias, Z. Li, D. Malkhi, A. Sonnino, A. Spiegelman, in:, International Conference on Financial Cryptography and Data Security, Springer Nature, 2022, pp. 279–295. Cohen, Shir, et al. “Be Aware of Your Leaders.” <i>International Conference on Financial Cryptography and Data Security</i>, vol. 13411, Springer Nature, 2022, pp. 279–95, doi:<a href="https://doi.org/10.1007/978-3-031-18283-9_13">10.1007/978-3-031-18283-9_13</a>. S. Cohen <i>et al.</i>, “Be aware of your leaders,” in <i>International Conference on Financial Cryptography and Data Security</i>, Grenada, 2022, vol. 13411, pp. 279–295. Cohen, Shir, Rati Gelashvili, Eleftherios Kokoris Kogias, Zekun Li, Dahlia Malkhi, Alberto Sonnino, and Alexander Spiegelman. “Be Aware of Your Leaders.” In <i>International Conference on Financial Cryptography and Data Security</i>, 13411:279–95. Springer Nature, 2022. <a href="https://doi.org/10.1007/978-3-031-18283-9_13">https://doi.org/10.1007/978-3-031-18283-9_13</a>. Cohen S, Gelashvili R, Kokoris Kogias E, et al. Be aware of your leaders. In: <i>International Conference on Financial Cryptography and Data Security</i>. Vol 13411. Springer Nature; 2022:279-295. doi:<a href="https://doi.org/10.1007/978-3-031-18283-9_13">10.1007/978-3-031-18283-9_13</a> Cohen, S., Gelashvili, R., Kokoris Kogias, E., Li, Z., Malkhi, D., Sonnino, A., &#38; Spiegelman, A. (2022). Be aware of your leaders. In <i>International Conference on Financial Cryptography and Data Security</i> (Vol. 13411, pp. 279–295). Grenada: Springer Nature. <a href="https://doi.org/10.1007/978-3-031-18283-9_13">https://doi.org/10.1007/978-3-031-18283-9_13</a> 121682023-01-12T12:10:49Z2025-09-10T09:48:54Z