Channels: Horizontal Scaling and Confidentiality on Permissioned Blockchains

  • Elli Androulaki
  • Christian Cachin
  • Angelo De Caro
  • Eleftherios Kokoris-KogiasEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11098)


Sharding, or partitioning the system’s state so that different subsets of participants handle it, is a proven approach to building distributed systems whose total capacity scales horizontally with the number of participants. Many distributed ledgers have adopted this approach to increase their performance, however, they focus on the permissionless setting that assumes the existence of a strong adversary. In this paper, we deploy channels for permissioned blockchains. Our first contribution is to adapt sharding on asset-management applications for the permissioned setting, while preserving liveness and safety even on transactions spanning across-channels. Our second contribution is to leverage channels as a confidentiality boundary, enabling different organizations and consortia to preserve their privacy within their channels and still be part of a bigger collaborative ecosystem. To make our system concrete we map it on top of Hyperledger Fabric.



We thank Marko Vukolić and Björn Tackmann for their valuable suggestions and discussions on earlier versions of this work. This work has been supported in part by the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 780477 PRIViLEDGE.


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Elli Androulaki
    • 1
  • Christian Cachin
    • 1
  • Angelo De Caro
    • 1
  • Eleftherios Kokoris-Kogias
    • 2
    Email author
  1. 1.IBM Research - ZurichRüschlikonSwitzerland
  2. 2.EPFLLausanneSwitzerland

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