LightChain: A DHT-based Blockchain for Resource Constrained Environments

TL;DR

LightChain introduces a DHT-based blockchain architecture optimized for resource-constrained environments, enhancing efficiency, fairness, and security while significantly reducing storage and bootstrap times compared to traditional blockchains.

Contribution

It is the first blockchain architecture utilizing a DHT for efficient, fair, and secure operation in resource-limited settings, with proven scalability and performance benefits.

Findings

Requires 66 times less storage per node compared to Bitcoin and Ethereum.

Is approximately 380 times faster in bootstrapping a new node.

Demonstrates security and fairness through mathematical analysis and experiments with 10K nodes.

Abstract

As an append-only distributed database, blockchain is utilized in a vast variety of applications including the cryptocurrency and Internet-of-Things (IoT). The existing blockchain solutions have downsides in communication and storage efficiency, convergence to centralization, and consistency problems. In this paper, we propose LightChain, which is the first blockchain architecture that operates over a Distributed Hash Table (DHT) of participating peers. LightChain is a permissionless blockchain that provides addressable blocks and transactions within the network, which makes them efficiently accessible by all the peers. Each block and transaction is replicated within the DHT of peers and is retrieved in an on-demand manner. Hence, peers in LightChain are not required to retrieve or keep the entire blockchain. LightChain is fair as all of the participating peers have a uniform chance of being involved in the consensus regardless of their influence such as hashing power or stake. LightChain provides a deterministic fork-resolving strategy as well as a blacklisting mechanism, and it is secure against colluding adversarial peers attacking the availability and integrity of the system. We provide mathematical analysis and experimental results on scenarios involving 10K nodes to demonstrate the security and fairness of LightChain. As we experimentally show in this paper, compared to the mainstream blockchains like Bitcoin and Ethereum, LightChain requires around 66 times less per node storage, and is around 380 times faster on bootstrapping a new node to the system, while each LightChain node is rewarded equally likely for participating in the protocol.