tanguyenvn/blockchain-pos

A simple Blockchain using PoS consensus mechanism written in Python

Proof-of-Stake Blockchain

Introduction

This is a prototype of Blockchain using Proof-of-Stake Consensus mechanism. It was written in Python and actually based on a Udemy course.

• Cryptographic Signatures
• RSA Public Key Cryptography
• SHA-256 Hashes
• Transactions - The purpose of Transactions in a Blockchain Systems.
• Blocks - The most essential building block.
• Blockchains - Whats going on behind the scenes.
• P2P Network - How to find and communicate with other Nodes.
• REST API - How to communicate with your Blockchain System.
• Proof-of-Stake: Finding Consensus in a Network of mutually untrusted Nodes
• Threading & Parallelization

Suggested improvements

• Currently, all data is stored in process' memory. We can improve it by storing data in a persistent storage e.g. LevelDB
• Shorten the addresses of sender and receiver. So far, we're using public keys
• What if a staker is selected to be the next forger but is offline?

High level Components

UML Diagram

Getting started

• Install requirements.txt
• In case of error, run

pip3 uninstall PyCrypto
pip3 install -U PyCryptodome

• start P2P nodes

python3 Main.py localhost 10001

• Start API server

python3 Main.py localhost 10001 5001

• Query Blockchain and Transaction Pool status via API

http://localhost:5001/blockchain
http://localhost:5001/transactionPool

• Create and submit a transaction via API

python3 TestCreateTransaction.py