The adoption of blockchain in the Internet of Things (IoT) has been increasing due to the various benefits that blockchain brings, such as security and privacy. Current blockchain models for mobile IoT assume there are fixed, powerful edge devices capable of providing global communication to all the nodes in the network. However, due to the mobile nature of IoT or network partitioning problems (NPP), nodes can move out of a cell area and split into smaller independent peer-to-peer subnetworks. Existing blockchain structures either do not support the network partitioning problem or have limitations. This paper introduces a multidimensional, graph-based blockchain structure, that utilizes k-dimensional spatiotemporal space, to address the challenges of applying blockchain in mobile networks with limited resources. Experimental results show that a multidimensional blockchain structure can improve scalability and efficiency as the blockchain grows in size, similar to logarithmic growth, and reduce the longest chain length by more than 99.99% compared to the traditional chain-based blockchain structure.
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Quantifying location privacy in permissioned blockchain-based internet of things (IoT)
Recently, blockchain has received much attention from the mobility-centric Internet of Things (IoT). It is deemed the key to ensuring the built-in integrity of information and security of immutability by design in the peer-to-peer network (P2P) of mobile devices. In a permissioned blockchain, the authority of the system has control over the identities of its users. Such information can allow an ill-intentioned authority to map identities with their spatiotemporal data, which undermines the location privacy of a mobile user. In this paper, we study the location privacy preservation problem in the context of permissioned blockchain-based IoT systems under three conditions. First, the authority of the blockchain holds the public and private key distribution task in the system. Second, there exists a spatiotemporal correlation between consecutive location-based transactions. Third, users communicate with each other through short-range communication technologies such that it constitutes a proof of location (PoL) on their actual locations. We show that, in a permissioned blockchain with an authority and a presence of a PoL, existing approaches cannot be applied using a plug-and-play approach to protect location privacy. In this context, we propose BlockPriv, an obfuscation technique that quantifies, both theoretically and experimentally, the relationship between privacy and utility in order to dynamically protect the privacy of sensitive locations in the permissioned blockchain.
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- Award ID(s):
- 1851890
- NSF-PAR ID:
- 10390162
- Editor(s):
- Vincent Poor and Zhu Han
- Date Published:
- Journal Name:
- MobiQuitous '19: Proceedings of the 16th EAI International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services
- Page Range / eLocation ID:
- 116 to 125
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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