---
_id: '18071'
abstract:
- lang: eng
  text: Recent advancements on DAG-based consensus protocols allow for blockchains
    with improved metrics and properties, such as throughput and censorship-resistance.
    Variants of the Bullshark [18] consensus protocol are adopted for practical use
    by the Sui blockchain, for improved latency. However, the protocol is leader-based,
    and is strongly affected by crashed leaders that can lead to various performance
    issues, for example, decreased transaction throughput. In this paper, we propose
    HammerHead, a DAG-based consensus protocol, that is inspired by Carousel [8] and
    provides Leader-Utilization. Our proposal differs from Carousel, which is built
    for a chained consensus protocol; in HammerHead chain quality is inherited by
    the DAG. HammerHead needs to preserve safety and liveness, despite validators
    committing leader vertices asynchronously. The key idea is to update leader schedules
    dynamically, based on the validators' scores during the previous schedule. We
    implement HammerHead and show a minor improvement in performance for cases without
    faults. The major improvements in comparison to Bullshark appear in faulty settings.
    Specifically, we show a drastic, 2x-latency improvement and up to 40% increased
    throughput when crash faults occur (100 validators, 33 faults).
acknowledgement: This work is supported by Mysten Labs. We thank the Mysten Labs Engineering
  teams for valuable feedback broadly, and specifically to Laura Makdah for helping
  implementing the early reputation score system for validators and Dmitry Perelman
  for managing the overall implementation effort.
article_processing_charge: No
arxiv: 1
author:
- first_name: Giorgos
  full_name: Tsimos, Giorgos
  last_name: Tsimos
- first_name: Anastasios
  full_name: Kichidis, Anastasios
  last_name: Kichidis
- first_name: Alberto
  full_name: Sonnino, Alberto
  last_name: Sonnino
- first_name: Eleftherios
  full_name: Kokoris Kogias, Eleftherios
  id: f5983044-d7ef-11ea-ac6d-fd1430a26d30
  last_name: Kokoris Kogias
citation:
  ama: 'Tsimos G, Kichidis A, Sonnino A, Kokoris Kogias E. HammerHead: Leader reputation
    for dynamic scheduling. In: <i>Proceedings - International Conference on Distributed
    Computing Systems</i>. IEEE; 2024:1377-1387. doi:<a href="https://doi.org/10.1109/ICDCS60910.2024.00129">10.1109/ICDCS60910.2024.00129</a>'
  apa: 'Tsimos, G., Kichidis, A., Sonnino, A., &#38; Kokoris Kogias, E. (2024). HammerHead:
    Leader reputation for dynamic scheduling. In <i>Proceedings - International Conference
    on Distributed Computing Systems</i> (pp. 1377–1387). Jersey City, NJ, United
    States: IEEE. <a href="https://doi.org/10.1109/ICDCS60910.2024.00129">https://doi.org/10.1109/ICDCS60910.2024.00129</a>'
  chicago: 'Tsimos, Giorgos, Anastasios Kichidis, Alberto Sonnino, and Eleftherios
    Kokoris Kogias. “HammerHead: Leader Reputation for Dynamic Scheduling.” In <i>Proceedings
    - International Conference on Distributed Computing Systems</i>, 1377–87. IEEE,
    2024. <a href="https://doi.org/10.1109/ICDCS60910.2024.00129">https://doi.org/10.1109/ICDCS60910.2024.00129</a>.'
  ieee: 'G. Tsimos, A. Kichidis, A. Sonnino, and E. Kokoris Kogias, “HammerHead: Leader
    reputation for dynamic scheduling,” in <i>Proceedings - International Conference
    on Distributed Computing Systems</i>, Jersey City, NJ, United States, 2024, pp.
    1377–1387.'
  ista: 'Tsimos G, Kichidis A, Sonnino A, Kokoris Kogias E. 2024. HammerHead: Leader
    reputation for dynamic scheduling. Proceedings - International Conference on Distributed
    Computing Systems. ICDCS: International Conference on Distributed Computing Systems,
    1377–1387.'
  mla: 'Tsimos, Giorgos, et al. “HammerHead: Leader Reputation for Dynamic Scheduling.”
    <i>Proceedings - International Conference on Distributed Computing Systems</i>,
    IEEE, 2024, pp. 1377–87, doi:<a href="https://doi.org/10.1109/ICDCS60910.2024.00129">10.1109/ICDCS60910.2024.00129</a>.'
  short: G. Tsimos, A. Kichidis, A. Sonnino, E. Kokoris Kogias, in:, Proceedings -
    International Conference on Distributed Computing Systems, IEEE, 2024, pp. 1377–1387.
conference:
  end_date: 2024-07-26
  location: Jersey City, NJ, United States
  name: 'ICDCS: International Conference on Distributed Computing Systems'
  start_date: 2024-07-23
date_created: 2024-09-15T22:01:41Z
date_published: 2024-07-26T00:00:00Z
date_updated: 2025-09-08T09:42:36Z
day: '26'
department:
- _id: ElKo
doi: 10.1109/ICDCS60910.2024.00129
external_id:
  arxiv:
  - '2309.12713'
  isi:
  - '001304430200120'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2309.12713
month: '07'
oa: 1
oa_version: Preprint
page: 1377-1387
publication: Proceedings - International Conference on Distributed Computing Systems
publication_identifier:
  eissn:
  - 2575-8411
  isbn:
  - '9798350386059'
  issn:
  - 1063-6927
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'HammerHead: Leader reputation for dynamic scheduling'
type: conference
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
year: '2024'
...