Nowadays Blockchain is becoming a very powerful technology due to its unique advantageous features as immutability, decentralization, distributed and shared database or ledger. There are various platform available today as ethereum, bitcoin, hyperledger etc. which make yours blockchain application public or online so that it can be used by everyone. But blockchain has append only database means once the data or asset is to written on it, never deleted. That’s why developers have to validate their application before deploying it on the blockchain. There are mainly two ways to test the accuracy of any blockchain application. First one is write the blockchain code from scratch and run it on the local machine and validate its accuracy. Second one is run your application at any blockchain simulator and test your results. Former one is a very complex method and latter one makes our work easy. That’s why like traditional network simulators, we have blockchain simulators at which we can test our application before deploying it into the mainnet. We describe some of the blockchain simulators or testnets below- This is the official test network of bitcoin network for validating or checking the value of our application. In this we can use faucets to provide fake coins that have no real value. Some of them are: 1. Bitcoin Testnet: Bitcoin Testnet Explorer Bitcoin Testnet BlockCypher Testnet Explorer Bitcoin Testnet Faucet Similar as in the bitcoin testnet, ethereum also has their testnets that are public and private both (depending on the user requirement) as: 2. Ethereum Testnet: Ropsten Network Kovan network Rinkeby network GanacheCLI Truffle Framework Remix IDE Hyperledger fabric is one of the example of permissioned blockchain that are mostly used nowadays. It also has testnets for validation of decentralized application as 3. Hyperledger Testnet: IBM Blockchain Platform extension for Visual Studio Code REMME Hyperledger Umbra Blockchain demo is a simulator developed by . It shows the basic operations of blockchain as hashing, mining, distribution etc. For more information of it please visit: 4. Blockchain Demo: Anders Brownworth https://anders.com/blockchain/ It is another fast blockchain simulator for large-scale peer-to-peer networks. It is a bitcoin like simulator that uses the concept of fast forward computing to improve scalability issues instead of proof of work (POW). For more information of it please visit: 5. VIBES: https://github.com/i13-msrg/vibes SimBlock is an open source blockchain network simulator, developed by Distributed Systems Group, Tokyo Institute of Technology. SimBlock is event-driven and is suitable for use in blockchain network research. SimBlock also has a visualization tool, by which you can see the transition of block propagation. For more information of it please visit: 6. SimBlock: https://dsg-titech.github.io/simblock/ It is a framework for modeling and simulate a Blockchain protocol. It follows a discrete event simulation model. Currently, there are only 2 models to simulate and . For more information of it please visit: 7. BlockSim: Bitcoin Ethereum https://github.com/blockbirdLabs/blocksim It is a bitcoin only open source simulator written in NS3. For more information of it please visit: 8. Bitcoin Simulator: https://arthurgervais.github.io/Bitcoin-Simulator/ It is a free Trading Simulator for Bitcoin and 78 cryptocurrencies to play your investment strategies live without the need to spend real money. For more information of it please visit: 9. CryptoSpaniards Simulator: https://cryptospaniards.com/simulator/ It is a framework for analyzing private blockchains as Ethereum, Parity and Hyperledger. For more information of it please visit: 10. BLOCKBENCH: https://github.com/ooibc88/blockbench Another approach of testing the network is by building one. Anyone can implement its own blockchain from scratch for more clarifying the working of blockchain and do some innovation in blockchain modules. They can use any language or tool for building it as JAVA, Python, NS3 network simulator, Matlab simulator etc. Please go to the below links for more help: https://hackernoon.com/learn-blockchains-by-building-one-117428612f46 https://medium.com/coinmonks/building-a-simple-blockchain-data-structure-with-python-e7ebd448647a https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa https://www.influencive.com/creating-your-first-blockchain-with-java-code/ https://www.mathworks.com/matlabcentral/fileexchange/65419-matlab-blockchain-example Readers can also simulate blockchain using game theory or with queuing theory. For more info please refer to below papers: A Survey on Applications of Game Theory in Blockchain Simulation Model for Blockchain Systems Using Queuing Theory Finally we can see that there are various simulation or implementation available in the market for testing the blockchain. For more information about blockchain simulator or blockchain application you can contact me at mail or ping me at social network websites. kaur.3@iitj.ac.in
