Performance Comparison and Analysis of Paxos, Raft and PBFT Using NS3

In today’s technological developments, the need for a system to guarantee security, transparency, and transaction speed is the underlying point in creating new technologies. Blockchain is a digital data recording and storage technology that is interconnected between one device and another and cannot be changed by anyone due to the implementation of cryptography. The consensus algorithm is a mechanism used by computers and blockchain systems in approving the addition of new data. In Blockchain, no one authority oversees the activities where the entire system is made in a decentralized manner so that decision making, verification, and authentication are on the blockchain must involve all users in it. Therefore, the consensus is needed by the blockchain in forming an efficient, fair, reliable, and secure mechanism so that all parties involved in it can have a vote. In this paper, we evaluate the performance of several consensus algorithms, such as Paxos, Raft, and PBFT, by simulating the time to reach consensus using the NS3 network simulator. We chose Paxos because this algorithm is the forerunner of the consensus algorithm, while Raft and PBFT are algorithms that have evolved from Paxos, which are still widely implemented in blockchain technology until now. Finally, based on the evaluation results, it was found that the PBFT algorithm has a speed five times faster than Raft and six times faster than Paxos to reach consensus. So we consider the PBFT algorithm to have the best speed and scalability. We hope that this research can be used as a reference for implementing the consensus algorithm in the development of blockchain technology.