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arXiv · 2107.10238

Secure Access Control for DAG-based Distributed Ledgers

Lianna Zhao·Luigi Vigneri·Andrew Cullen·William Sanders·Pietro Ferraro·Robert Shorten
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Abstract

Access control is a fundamental component of the design of distributed ledgers, influencing many aspects of their design, such as fairness, efficiency, traditional notions of network security, and adversarial attacks such as Denial-of-Service (DoS) attacks. In this work, we consider the security of a recently proposed access control protocol for Directed Acyclic Graph-based distributed ledgers. We present a number of attack scenarios and potential vulnerabilities of the protocol and introduce a number of additional features which enhance its resilience. Specifically, a blacklisting algorithm, which is based on a reputation-weighted threshold, is introduced to handle both spamming and multi-rate malicious attackers. The introduction of a solidification request component is also introduced to ensure the fairness and consistency of network in the presence of attacks. Finally, a timestamp component is also introduced to maintain the consistency of the network in the presence of multi-rate attackers. Simulations to illustrate the efficacy and robustness of the revised protocol are also described.

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Lianna Zhao, Luigi Vigneri, Andrew Cullen, William Sanders, Pietro Ferraro, Robert Shorten. 2021-07-20. Secure Access Control for DAG-based Distributed Ledgers. https://arxiv.org/abs/2107.10238

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