Hieraledger: Towards malicious gateways in appendable-block blockchain constructions for IoT

Appendable-block blockchain was established in an effort to standardize a blockchain architecture for heterogeneous Internet of Things devices. In current constructions, the main disadvantage lies in the full trust of gateways, which can launch coordinated and individual eclipse attacks against IoT sensing devices without being caught. This paper introduces Hieraledger, a novel commitment protocol for exposing malicious gateways in appendable-block blockchain constructions. To minimize the likelihood of eclipse attacks, each sensing device selects more than one gateway based on a novel reputation scoring model and the self-valuation of its privacy. To expose malicious gateways, our protocol employs fail-stop signatures thwarting signature forging, cryptographic hash functions, and a novel Merkle appendable tree. For each sensing device, we generate a resource-aware repudiable cryptographic proof of origin evidence. For gateway nodes, we generate a chain of commitment-based non-repudiable cryptographic proofs of delivery evidence. To demonstrate the security and robustness of our scheme, we analyze it under a solid theoretical security model. Based on our findings, our protocol enables sensing devices to seek arbitration and expose malicious gateways to the network. The present study is a further addition to the growing body of research into privacy preserving blockchain solutions for the Internet of Things