On and Off-Blockchain Enforcement of Smart Contracts

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11339)


Emerging blockchain technology is a promising platform for implementing smart contracts. But there is a large class of applications, where blockchain is inadequate due to performance, scalability, and consistency requirements, and also due to language expressiveness and cost issues that are hard to solve. In this paper we explain that in some situations a centralised approach that does not rely on blockchain is a better alternative due to its simplicity, scalability, and performance. We suggest that in applications where decentralisation and transparency are essential, developers can advantageously combine the two approaches into hybrid solutions where some operations are enforced by enforcers deployed on–blockchains and the rest by enforcers deployed on trusted third parties.


Smart contracts Blockchain Monitoring Enforcement On chain Off chain IoT Privacy Trust 



Carlos Molina-Jimenez is collaborating with the HAT Community Foundation under support of Grant RG90413 NRAG/536. Ioannis Sfykaris was partly supported by the EU Horizon 2020 project PrismaCloud ( under GA No. 644962.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Computer LaboratoryUniversity of CambridgeCambridgeUK
  2. 2.School of ComputingNewcastle UniversityNewcastle upon TyneUK
  3. 3.Hat Community FoundationCambridgeUK

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