Blockchain in the Quantum World

TL;DR

This paper systematically reviews blockchain's reliance on cryptography vulnerable to quantum attacks, analyzing research gaps and the distribution of solutions across blockchain layers.

Contribution

It provides a comprehensive literature review on quantum vulnerabilities in blockchain and identifies research gaps and distribution of solutions across layers.

Findings

30% of solutions target the data layer

24% focus on application and presentation layer

6% of solutions involve other distributed ledger technologies

Abstract

Blockchain is one of the most discussed and highly accepted technologies, primarily due to its application in almost every field where third parties are needed for trust. Blockchain technology relies on distributed consensus for trust, which is accomplished using hash functions and public-key cryptography. Most of the cryptographic algorithms in use today are vulnerable to quantum attacks. In this work, a systematic literature review is done so that it can be repeated, starting with identifying the research questions. Focusing on these research questions, literature is analysed to find the answers to these questions. The survey is completed by answering the research questions and identification of the research gaps. It is found in the literature that 30% of the research solutions are applicable for the data layer, 24% for the application and presentation layer, 23% for the network layer, 16% for the consensus layer and only 1% for hardware and infrastructure layer. We also found that 6% of the solutions are not blockchain-based but present different distributed ledger technology.