SINERGI Vol. 25, No. 3, October 2021: 381-392 http://publikasi.mercubuana.ac.id/index.php/sinergi http://doi.org/10.22441/sinergi.2021.3.015 N. A. Akbar et al., Reducing Overhead of Self-Stabilizing Byzantine Agreement Protocols … 381 REDUCING OVERHEAD OF SELF-STABILIZING BYZANTINE AGREEMENT PROTOCOLS FOR BLOCKCHAIN USING HTTP/3 PROTOCOL: A PERSPECTIVE VIEW Nur Arifin Akbar 1* , Andi Sunyoto 1 , M. Rudyanto Arief 1 , Wahyu Caesarendra 2 1 Department of Informatics Engineering, Universitas Amikom Yogyakarta, Indonesia 2 Faculty of Integrated Technologies, Universiti Brunei Darussalam, Brunei Abstract Today, there is a tendency to reduce the dependence on local computation in favor of cloud computing. However, this inadvertently increases the reliance upon distributed fault-tolerant systems. In a condition that forced to work together, these systems often need to reach an agreement on some state or task, and possibly even in the presence of some misbehaving Byzantine nodes. Although non- trivial, Byzantine Agreement (BA) protocols now exist that are resilient to these types of faults. However, there is still a risk for inconsistencies in the application state in practice, even if a BA protocol is used. A single transient fault may put a node into an illegal state, creating a need for new self-stabilizing BA protocols to recover from illegal states. As self-stabilization often comes with a cost, primarily in the form of communication overhead, a potential lowering of latency - the cost of each message - could significantly impact how fast the protocol behaves overall. Thereby, there is a need for new network protocols such as QUIC, which, among other things, aims to reduce latency. In this paper, we survey current state- of-the-art agreement protocols. Based on previous work, some researchers try to implement pseudocode like QUIC protocol for Ethereum blockchain to have a secure network, resulting in slightly slower performance than the IP-based blockchain. We focus on consensus in the context of blockchain as it has prompted the development and usage of new open-source BA solutions that are related to proof of stake. We also discuss extensions to some of these protocols, specifically the possibility of achieving self - stabilization and the potential integration of the QUIC protocol, such as PoS and PBFT. Finally, further challenges faced in the field and how they might be overcome are discussed. This is an open access article under the CC BY-NC license Keywords: Blockchain; Byzantine Agreement; PBFT; Proof of Work; QUIC protocol; Self-stabilization; Article History: Received: January 5, 2021 Revised: April 15, 2021 Accepted: May 17, 2021 Published: September 29, 2021 Corresponding Author: Nur Arifin Akbar Department of Informatics Engineering, Universitas Amikom Yogyakarta, Indonesia Email: nur.1233@students.amikom.ac.id INTRODUCTION This first section provides a background to the agreement in distributed systems that are prone to failures. After that, blockchain is presented and how it utilizes distributed agreement. Finally, the section is concluded with the aim of this paper. Distributed systems are a fundamental part of many services used Today, and applications often require these systems to be resilient to failures and malicious actors. These systems utilize different sets of protocols to maintain an agreement amongst themselves. Being able to reach an agreement or consensus is necessary as the system is expected to perform coordinated tasks, such as removing misbehaving nodes from the network. Misbehaving nodes, meaning nodes that are not functioning correctly, exist due to the nature of distributed systems, where networks may fail, and malicious nodes may be introduced to the system. In order to provide resilience against malicious behavior, nodes are considered to be able to act Byzantine.