Crash-Tolerant Consensus in Directed Graph Revisited (Extended Abstract)

  • Ashish ChoudhuryEmail author
  • Gayathri Garimella
  • Arpita Patra
  • Divya Ravi
  • Pratik Sarkar
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11085)


Fault-tolerant distributed consensus is a fundamental problem in secure distributed computing. In this work, we consider the problem of distributed consensus in directed graphs tolerating crash failures. Tseng and Vaidya (PODC’15) presented necessary and sufficient condition for the existence of consensus protocols in directed graphs. We improve the round and communication complexity of their protocol. Moreover, we prove that our protocol requires the optimal number of communication rounds, required by any protocol belonging to a restricted class of crash-tolerant consensus protocols in directed graphs.


Directed graph Consensus Crash failure Round complexity 



We thank the anonymous referees of SIROCCO 2018 for their helpful comments. The work of the first two authors is financially supported by Infosys foundation. The third author would like to acknowledge the financial support by SERB Women Excellence Award from Science and Engineering Research Board of India and INSPIRE Faculty Fellowship from Department of Science & Technology, India


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Ashish Choudhury
    • 1
    Email author
  • Gayathri Garimella
    • 3
  • Arpita Patra
    • 2
  • Divya Ravi
    • 2
  • Pratik Sarkar
    • 4
  1. 1.International Institute of Information Technology BangaloreBengaluruIndia
  2. 2.Department of Computer Science and AutomationIndian Institute of ScienceBengaluruIndia
  3. 3.Oregon State UniversityCorvallisUSA
  4. 4.Boston UniversityBostonUSA

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