Public Blockchains Scalability: An Examination of Sharding and Segregated Witness

  • Amritraj Singh
  • Reza M. PariziEmail author
  • Meng Han
  • Ali Dehghantanha
  • Hadis Karimipour
  • Kim-Kwang Raymond Choo
Part of the Advances in Information Security book series (ADIS, volume 79)


Recently, public and permissionless blockchains such as Bitcoin and Ethereum have been facing a formidable challenge in the form of scalability which has hindered their expected growth. Both Bitcoin and Ethereum can process fewer than 20 transactions per second, which is significantly lower than their centralized counterpart such as VISA which can process approximately 1700 transactions per second. In realizing this hindrance for wide range adoption of blockchains for building advanced and large scalable systems, the blockchain community has proposed several solutions including Sharding and Segregated Witness (SegWit). Although these proposals are innovative, they still suffer from the blockchain trilemma of scalability, security, and decentralization. Moreover, at this time, little is known or discussed regarding factors related to design choices, feasibility, limitations, and other issues in adopting these solutions in public and permissionless blockchains. Hence, this paper provides the first comprehensive state-of-the-art review of sharding and segregated witness in public and permissionless blockchains, identifying current advancements, highlighting their limitations and discussing possible remedies for the overall improvement of the blockchain domain.


Sharding Segregated witness Blockchain Scalability Ethereum Bitcoin 


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Department of Software Engineering and Game DevelopmentKennesaw State UniversityMariettaUSA
  2. 2.College of Computing and Software EngineeringKennesaw State UniversityMariettaUSA
  3. 3.Department of Information TechnologyKennesaw State UniversityMariettaUSA
  4. 4.Cyber Science LabSchool of Computer Science, University of GuelphGuelphCanada
  5. 5.School of Engineering, University of GuelphGuelphCanada
  6. 6.Department of Information Systems and Cyber SecurityUniversity of Texas at San AntonioSan AntonioUSA

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