Developing an Ethereum Cryptocurrency on Windows

This is a step-by-step guide for developing an Ethereum-based cryptocurrency on Windows.

To start the project, we need to set up a development environment with the following requirements:

  • A code editor
  • Source control
  • Unit tests
  • Debugging

For code editor, we use Visual Studio code for the following reasons:

  1. VS Code integrates very well with Git for source control. Git is currently the best choice for  source control.
  2. VS Code works well with Truffle framework that manages unit tests.
  3. VS Code works well with Truffle for debugging

Besides that, Visual Studio code is a great tool for editing Solidity smart contracts and is available on Windows, Mac & Linux.

I. Installation of  the Packages

Step1: Install Chocolatey

Launch PowerShell as administrator. In PowerShell, enter the following command:

 
Set-ExecutionPolicy Bypass

*The Set-ExecutionPolicy changes the user preference for the Windows PowerShell execution policy.*Bypass-Nothing is blocked and there are no warnings or prompts. This execution policy is designed for configurations in which a Windows PowerShell script is built in to a a larger application or for configurations in which Windows PowerShell is the foundation for a program that has its own security model.
* Why Chocolatey-“You’ve never deployed software faster than you will with Chocolatey.” -Rob Reynolds. Chocolatey is a software management automation.

Install Chocolatey by entering the following code:

iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))

*https://chocolatey.org/docs/installation
*iex-invoke expression-The Invoke-Expression cmdlet evaluates or runs a specified string as a command and returns the results of the expression or command. Without Invoke-Expression, a string submitted at the command line would be returned (echoed) unchanged.

*A cmdlet (pronounced “command-let”) is a lightweight Windows PowerShell script that performs a single function.

* https://chocolatey.org/install.ps1 downloads the Chocolatey installation zip file, unzips it and continues the installation by running a scripts in the tools section of the package.

After installation completed, close and reopen PowerShell as administrator again.

Step 2 Install Visual Studio Code, Git and Node.js

Enter the following code in PowerShell:

choco install visualstudiocode -y 
choco install git -y  
choco install nodejs -y 

*Git (/ɡɪt/[7]) is a version control system for tracking changes in computer files and coordinating work on those files among multiple people. It is primarily used for source code management in software development,[8] but it can be used to keep track of changes in any set of files. As a distributed revision control system, it is aimed at speed, data integrity] and support for distributed, non-linear workflows.

*Node.js is a JavaScript runtime built on Chrome’s V8 JavaScript engine.

*As an asynchronous event driven JavaScript runtime, Node is designed to build scalable network applications. In programming, asynchronous events are those occurring independently of the main program flow. Asynchronous actions are actions executed in a non-blocking scheme, allowing the main program flow to continue processing

Close and reopen PowerShell before proceeding to the next step

Step 3 Install Truffle Framework

Truffle is a world class development environment, testing framework and asset pipeline for Ethereum, aiming to make life as an Ethereum developer easier

(https://truffleframework.com/docs). We use npm (Node Package Manager) to install Truffle Framework. Enter the following code:

npm install -g truffle

You can check the version of installed packages with the following code:

node -v 
npm -v  
truffle --version 

The output is as shown in Figure 1.

Figure 1

II. Configuring VS Code for Ethereum Blockchain Development

Step 1 Choose the folder for your project

Choose a folder you prefer for your project and enter the following code:

mkdir TruffleTest; cd TruffleTest; code .

The final command in the chain is “Code .”, which opens an instance of Visual Studio Code in the folder from which the command is executed.

Step 2  Install Solidity in the VS Code IDE

In the VS Code IDE, search for Solidity and install it

Step 3  Install  Material Icon Theme

In the VS Code , install Material Icon Theme

Now you have the VS integrated with PowerShell IDE for Ethereum Blockchain development.

III. Creating a Blockchain Application

We will create a sample cryptocurrency and a smart contract using the built-in sample MetaCoin in Truffle. Now, download the  files that can be compiled and deployed to a simulated blockchain using Truffle.

The code is

truffle unbox metacoin

The output should looks as shown in Figure 2.

Figure 2

After downloading Truffle metacoin, we should be able to view two important application files written in Solidity, MetaCoin.sol and ConvertLib.sol, in Figure 3.

* Solidity is a contract-oriented, high-level language for implementing smart contracts. It was influenced by C++, Python and JavaScript and is designed to target the Ethereum Virtual Machine (EVM).

*the Ethereum Virtual Machine is designed to serve as a runtime environment for smart contracts based on Ethereum.

Figure 3

These two files can be compiled and deployed to a simulated blockchain using Truffle.

To compile the smart contract, using the following command

truffle compile

*Or use truffle.cmd compile if there is error as shown in Figure 4.

Figure 4

*Source: https://ethereum.stackexchange.com/questions/21017/truffle-microsoft-jscript-runtime-error

After compilation completed, You will notice that a ‘build’ folder has been added to the list of files, which contains the compiled json files ConvertLib.json, MetaCoin.json, and Migrations.json, as shown in Figure 5.

Figure 5

IV Deploying the Contract

To deploy the contract, we shall migrate the contract  to a test network in truffle development environment.

The ‘develop’ command appears in  the Truffle development console environment. This will set up a kind of dummy blockchain, that operates similarly to the real Ethereum blockchain, and allows us to test deployment and execution of the code without needing to interface with an actual blockchain.

To compile the contract, key in the following command

truffle develop

This command will launch the truffle development environment, automatically configured with 10 accounts and keys. The output is as shown in Figure 6.

Figure 6

To deploy the compiled contract to the Truffle environment, enter the following command:

migrate

This will deploy the contracts to the test environment. The output is as shown in Figure 7.

Figure 7

To test the contract, enter the following command

test

You will see the output as shown in Figure 8.

Figure 8

To exit the Truffle console, type ctrl+D

To reenter the Truffle console, enter the following code

truffle develop 
migrate --reset  
test 

V Interacting with the contract with Web3

We have deployed and test the contract, now let’s do something with the contract. We will need to use the Web3 framework to interact with the smart contract on the Ethereum blockchain. Web3 is a JavaScript library which is bundled into the Truffle development console.

When the Truffle development console is started, it automatically configures 10 addresses, and assigns each of the addresses 100  Eth. You can check the ten available addresses by entering the following code:

web3.eth.accounts

The output is as shown in Figure 9.

Figure 9

You can display individual account using the following syntax

web3.eth.accounts[n]

For example, enter the following code to see the output

web3.eth.accounts[2]

The output is as shown in Figure 10.

Figure 10

Functions in the MetaCoin.sol file

There are four functions in the MetaCoin.sol file, as follows:

  • MetaCoin, the constructor. It is called when the contract is deployed.
  • sendCoin, for transferring coins between addresses.
  • getBalanceInEth, to convert between MetaCoins, and Ethereum.
  • getBalance, to show the balance in the requested address.

*  A constructor is a special method of a class or structure in object-oriented programming that initializes an object of that type. A constructor is an instance method that usually has the same name as the class, and can be used to set the values of the members of an object, either to default or to user-defined values.

The constructor MetaCoin comprises only one line

balances[tx.origin] = 10000;

*You can change this to any amount

This code initialises  the transaction to 10000 MetaCoin(Not Eth)

The initial address is

Web3.eth.accounts[0]

Checking Balance using the getBalance() method

You can check the balance of any account using the following code

web3.eth.getBalance(web3.eth.accounts[n]).toNumber()

Will display the balance in wei. To convert it to ether, you need to divide it by 10^18

You can use

web3.eth.getBalance(web3.eth.accounts[n]).toNumber()/1000000000000000000

Or

web3.fromWei(web3.eth.getBalance(web3.eth.accounts[n]),'ether').toNumber();

For example, to check the balance of account 0, enter the following code

web3.eth.getBalance(web3.eth.accounts[0]).toNumber() 

**The cryptocurrency generated by the getBalance function  is Wei

1 Ether =  1,000,000,000,000,000,000 Wei (1018) or 1 Wei=10^-18 Ether

The output is as shown in Figure 11.

Figure 11

To check the balance in Ether for account 0, enter the following command:

web3.fromWei(web3.eth.getBalance(web3.eth.accounts[0]),'ether').toNumber();

The output is as shown in Figure 12.

Figure 12

To check the balance of Web3.eth.accounts[0] in MetaCoin(not ether), use the following command:

MetaCoin.deployed().then(function(instance){return instance.getBalance.call(web3.eth.accounts[0]);}).then(function(value){return value.toNumber()});

The output is as shown in Figure 13.

Figure 13

The sendCoin Function

To send metacoin from account[0] to account[1], use the following command

MetaCoin.deployed().then(function(instance){return instance.sendCoin(web3.eth.accounts[1], 100);});

To send metacoin from account[m] to account[n], use the following command

MetaCoin.deployed().then(function(instance) { return instance.sendCoin(web3.eth.accounts[n], 10, {from:web3.eth.accounts[m]});})

Example

MetaCoin.deployed().then(function(instance) { return instance.sendCoin(web3.eth.accounts[1], 1000, {from: web3.eth.accounts[0]});})

The output is as shown in Figure 14.

Figure 14

The check whether the transaction is successful , we can check the balance of both accounts. (Note that this is the MetaCoin balance, NOT the Eth balance)

MetaCoin.deployed().then(function(instance){return instance.getBalance.call(web3.eth.accounts[0]);}).then(function(value){return value.toNumber()});

The output is as shown in Figure 15.

Figure 15

To convert MetaCoin to Ether, use the following code

MetaCoin.deployed().then(function(instance){return instance.getBalanceInEth.call(web3.eth.accounts[n]);}).then(function(value){return value.toNumber()});

Example

MetaCoin.deployed().then(function(instance){return instance.getBalanceInEth.call(web3.eth.accounts[0]);}).then(function(value){return value.toNumber()});

The output is as shown in Figure 16.

Figure 16

Debugging the Transaction

In the sendCoin() example,  a transaction has occurred on the blockchain. This transaction can be stepped through line by line, using the Truffle debugger. To do this , the Truffle debug command is used, passing in the transaction hash. This hash can be found in the console output following the sendCoin function call.

The command is

truffle(develop)> debug '0x4ca1828eb19679fbdd23722c62f11f2ddb4d3b3b229ffa7676bfaae924750ba6'

This will start the Truffle debugger. The instructions for interacting with the debugger are printed to the console, as shown in Figure 17.

Figure 17

You should start by adding a watch to the passed variables. do this by entering the following command:

+: receiver 
+: amount 

As you step through the code, the values passed into the function will be shown. Note, these are ‘undefined’ at the start of the function call.

You can press the enter key a few times to step through the code that was executed in this transaction. The output is as shown in Figure 18.

Figure 18


The debug commands can be used to inspect the variables, and add watched variables, as shown in Figure 19.

Figure 19

You can try to enter other commands.

Lastly, type quit to quit debugger

Deploying Your MetaCoin Contract with Truffle

Deploy to Ganache

Ganache is your personal Ethereum blockchain which is convenient for testing and interacting with your contracts during development. It ships with a helpful GUI that allows you to see available test accounts quickly, explore transactions, read logs, and see how much gas was consumed. Configure your truffle.js and truffle.config.js  for the Ganache network:

module.exports = {
  networks: {
    ganache: {
      host: "127.0.0.1",
      port: 7545,
      network_id: "*" // matching any id
    }
  }
};

Launch Ganache

In the Truffle console, enter the following command:

truffle migrate --network ganache

The output is as shown in Figure 20.

Figure 20

Ganache output is as shown in Figure 21.

Figure 21

Click transaction and compare the transaction hash. They are the same.

Figure 22

Deploy to Ropsten

Run a node connected to Ropsten and specify the address of the default (first) account to unlock. You will be prompted for a passphrase.

geth --unlock <account> --testnet --rpc --rpcapi eth,net,web3

Configuration for the Ropsten network:

module.exports = {
  networks: {
    ropsten: {
      host: "127.0.0.1",
      port: 8545,
      network_id: 3,
      gas: 4700000
    },
  }
};

Deploy to the Ropsten network:

truffle migrate --network ropsten

Deploy to Rinkeby

Rinkeby network is available only using geth client.

geth --unlock <account> --rinkeby --rpc --rpcapi eth,net,web3

Configuration for the Rinkeby network:

module.exports = {
 networks: {
   rinkeby: {
     host: "127.0.0.1",
     port: 8545,
     network_id: 4
   },
 }
};

Deploy to the Rinkeby network:

truffle migrate --network rinkeby








Plasma-The Solution for Security and Scalability

The Scalability Issue

Blockchain always faces the trade-off issue between security and scalability. Though their PoW consensus protocol guarantees near perfect security, it also slows down the processing speed significantly.  Currently, the Ethereum processing speed is 15 transactions per second while Bitcoin is 7 transactions per second. Both platform’s processing capacities are nowhere near Visa’s processing speed of 45,000 transactions per second. Furthermore, the increase in the number of dapps deployed on the main Ethereum main chain has caused congestion and slows down transactions tremendously. One of the most famous cases is Cryptokitties, it clogged up the Ethereum network in just a few weeks of deployment due to its unprecedented popularity.

In seeking a viable solution to the scalability issue, Vitalik Buterin and Joseph Poon have joined hands in conceptualizing and developing Plasma, a framework that can scale Ethereum processing power.  Joseph is also the co-founder of the Lightning network, a framework that has greatly increase Bitcoin processing speed. Both plasma and Lightning network are trustless multilayered blockchain networks.

Plasma

Plasma is a  system that comprises the main blockchain and the ‘child blockchains’ that branch out from the main blockchain(aka parent blockchain or root blockchain). The child blockchains can co-exist but function independently from the parent chain and each other. 

The Plasma system allows anyone to create their own child blockchains a.k.a plasma chains with their own smart contracts. Therefore, the Plasma system enables the creation of all kinds of use cases based on different business logic in their smart contracts. To ensure security, the root chain monitor and enforces the state in all the plasma chains and penalize the bad actors if there is proof of frauds.  In this way, the Plasma system makes off-chain transactions possible while relying on the Ethereum main blockchain to maintain its security. 

The Plasma Structure

Actually, the Plasma architecture is like a tree structure with the main Ethereum blockchain as the root. The child blockchains then branch out from the root blockchain, similar to branches grown out from the root of a tree. Every child chain, in turn, can spawn new child chains, the process can go on.  Therefore, the plasma structure constitute a hierarchy of blockchains,  as shown below:

Plasma Blockchain Structure

How does Plasma Works?

Plasma can greatly increase processing speed and throughput on the Ethereum blockchain because it allows off-chain transactions, similar to the payment channels of the Lightning network and other off-chain technologies. All the off-chain techniques take operations away from the main Ethereum blockchain.

State Channels

The concept of Plasma was derived from State Channels but improved on the latter. State channel works by creating an off-chain communication channel (a.k.a state channel )where transactions are not sent to the smart contract on the main chain, instead, they are sent through the Internet without touching the main blockchain.  It is only after all the transactions have been completed (for example, a crypto game has finished) that the final state is sent to the smart contract on the main chain, closing the channel in the process. The smart contract will check the legitimacy of the transactions and release the asset (such as some ETH or a prize) to the recipient. 

The state channel technique can improve scalability because it can reduce the number of transactions on the main blockchain. For example, a crypto chess game played between two players may involve hundreds of moves, which means hundreds of transactions will be executed on the Ethereum blockchain. However, if we use the state channel, we need to execute only 3 transactions that include registration of the players to initiate the game, submission of the final state to the blockchain and closing the channel. 

Steps in Implementing Plasma

Plasma works in a similar way but with a different approach. Instead of creating the channels, it creates the child blockchains, as illustrated earlier. Smart contracts are created on the main Ethereum blockchain(The root chain) and they  define the rules in the child blockchains. In other words, the smart contract serves as the root of the child blockchains. The child blockchains can employ their own consensus algorithm, such as proof of stake.  The blocks validator will submit the state of the child chain to the Root Chain smart contract periodically. The smart contract will register the state of each Child Chain in the form of block hashes of the Child Chain.

We can illustrate how Plasma works by examining a crypto game such as crytant crab or cryptokitties. The smart contract on the main chain will set the rules of the game, then deploy the actual game application smart contracts on the child-chain, which contains all of the game logic and rules.  The game assets such as characters or collectibles are created on the Ethereum main chain and then transferred onto the child-chain using the plasma root.  When the players play the games, all the executions are confined to the child chain, without interacting with the root chain. 

Plasma Exits

Plasma Exits is a  security mechanism behind Plasma that allows users in a Plasma Chain to stop participating in the chain, and move their funds or assets back to the root chain. When a user wishes to exit a particular child chain, he or she needs to submit an exit application.  The application is not immediately approved because a proof is required. This waiting period is called the challenge period, which means anyone can challenge the user’s claim by submitting a fraud proof. If the challenge is not valid or there is no challenge, the application will be approved and the user can exit and collect back his assets or funds.

Plasma is still evolving and now the Plasma team has come out with the improved version of Plasma known as Plasma cash.  We shall discuss this new version in coming articles.

References

Gas, Gas Price and Gas Limit

What is Gas?

By definition, gas is a unit that measures the amount of computational effort that it will take to execute certain operations on the Ethereum blockchain. The operations include sending tokens, deploying a smart contract, interacting with a contract, sending some ETH, launching an ICO, or anything else on the blockchain. Gas is needed to power the Ethereum Ecosystem, just like fuel is needed to power a car.

What is Gas Price?

As I have mentioned earlier, we need to use gas for every operation made on ethereum, regardless of whether your transaction succeeds or fails. Gas does not come free, we need to pay for it, just like paying for the gasoline in order to drive our cars. How much transaction fee we need to pay depends on the gas price and the gas limit.

Gas price is the amount of Ether you need to pay per unit of gas. It is measured in Gwei (1Gwei=0.0000000001 ETH).  Its value is determined by the miners, who can refuse to process the transaction with less than a certain gas price. The transaction fee is paid to the successful miner as a form of incentive that motivates the miners to maintain the nodes. Therefore, they have the controlling power over the gas price. We must have enough ether in our wallet to pay for the gas fees.

The transaction fee is calculated using the following formula

Transaction fee= Gas unit used x Gas price

For example, for a certain transaction,

gas unit used=103631

Gas price= 1Gwei or 0.000000001 Eth

So transaction fee= 103631×0.000000001 Eth=0.000103631 Eth  

You can see the actual output in a smart contract deployment on Etherescan, as shown in the figure below:

In addition, you can “bribe” the miners to do your work first by paying more gas fees. In this way, you can jump to the front of the queue so that your transaction can be processed first.  Even if the transaction fails, you still need to pay for the transaction fee because the miners must validate and execute your transaction.

Gas Limit

The Gas Limit is an estimation of the total amount of work to perform a transaction. It is not easy to compute the gas limit. Fortunately, there are many apps that set the limit for us. Typically, 21,000 Gas will satisfy most transactions. However, for more complex transactions such as sending ETH to an ICO smart contract, the gas limit will be much higher. The reason is such a transaction requires much more computational power.

If you set the limit is too low, your transaction may take too long to process and even fail. As a result, you will lose ETH for nothing. On the other hand, if your transaction was completed before reaching the gas limit, you get back the balance ETH. The Gas Limit protects you from spending unlimited ETH, just like what banks set your credit card limit so that you will not overspend.

Setting up a Private Ethereum Blockchain Network on Windows

Setting up a private Ethereum blockchain network is not an extremely difficult task for the coders. However,  it may be a bit of a challenge for the beginners.  I will skip some technical details and avoid using some jargon so that everyone can understand the basic concepts.  

Prerequisites

Before setting up the network, you need to install the following software:

  1. Visual Studio Code
  2.  git
  3.   NodeJs 
  4. Ethereum Wallet
  5. Geth

The go-ethereum client is commonly referred to as geth, which is the command line interface for running a full Ethereum node implemented in Go. By installing and running geth, you can run a private network or participate in the Ethereum main network. By running geth, you can perform the following tasks:

  • mine real ether
  • transfer funds between addresses
  • create smart contracts and send transactions
  • explore block history
  • and much much more

Creating the Genesis Block

To set up the private network, we need to create the Genesis block, the first block of the blockchain in our network. The code for the genesis block is written in JSON format.  JSON stores data as a  name/value pair.  For example:

"name": "John"  ,
"age": 30


It uses JavaScript syntax, but the format is text only.  Therefore,
JSON can be read and used as a data format by any programming language. You can use any text editor to write the JSON code(JSON: JavaScript Object Notation), I use Notedpad++. The sample code for the genesis block is as follows

{
"config":{
 "chainId": 45,
 "homesteadBlock": 0,
 "eip155Block": 0,
 "eip158Block": 0,
 "byzantiumBlock": 12
 },
 "alloc" : {},
 "coinbase" : "0x0000000000000000000000000000000000000000",
 "difficulty" : "0x20000",
 "extraData" : "",
 "gasLimit" : "0x2fefd8",
"nonce" : "0x0000000000000042",
 "mixhash" :"0x0000000000000000000000000000000000000000000000000000000000000000",
 "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
 "timestamp" : "0x00"
}

I will not discuss the contents of the genesis block here. Copy the code in a text editor and save the file as

myGenesis.json

Now run the following command in the command prompt to initialize the genesis block

geth init myGenesis.json

The output is as follows:

Once the genesis block is successfully created, a folder name ‘Ethereum’ will be created in the following path:

“C:\Users\admin\AppData\Roaming\Ethereum”

This folder contains the details of the Private Blockchain.

Starting the Private Network

Once the genesis block is created, run the following command to start the private network:

geth — networkid=5

*“networkid=1” stands for the main Ethereum network. So any random number apart from 1 can be given as the network id. Also, “console” is appended to the command in order to enable us to write commands while the network is running.

The output is as follows:

Launching the Ethereum Wallet

The output is as shown in the following figure. Notice that the network name is Private net.

Creating a New Account Address

You can create an address in the Ethereum Wallet application. The address can be created on the Ethereum Wallet App. In the ‘Wallets’ section, click on ‘Add Account’ to create a new account address.

To create new account using the Geth Console, use the following command:

geth account new

The output

Start Mining

To start mining on the private network,  Enter the geth console with  the following command

Geth --rpc console

In the Geth Console type

miner.start()

The output is as follows

Now you can see that the mining process is generating Ethers ,  as shown in the following figure. Bear in mind that these are fake Ethers and can only be used for a private test net.

Stop Mining

Type Ctrl+C in the geth console and key in the following command:

miner.stop()

Type Exit  to quit the geth console

What is Ethereum?

According to the Ethereum Foundation, 

Ethereum is a decentralized platform that runs smart contracts: applications that run exactly as programmed without any possibility of downtime, censorship, fraud or third-party interference.

These apps run on a custom built blockchain, an enormously powerful shared global infrastructure that can move value around and represent the ownership of property.

Definition of Ethereum

Based on the above descriptions, Ethereum is an open-source blockchain-based decentralized platform featuring smart contracts.  Indeed, Ethereum is a programmable blockchain that enables developers to build and deploy decentralized applications. Rather than providing users with a set of predefined applications like bitcoin, Ethereum allows users to create any kind of applications they wish. In this way, it serves as a platform for many different types of decentralized blockchain applications, including but not limited to cryptocurrencies.

Ethereum Virtual Machine

At the core of the Ethereum platform is the Ethereum Virtual Machine (“EVM”), which possesses its own programming language, known as the ‘EVM bytecode’.  It is the runtime environment that executes all of the smart contracts on the Ethereum network.

The Smart Contract code is written in high-level programming languages such as Solidity. The code is compiled to the EVM bytecode so that the Ethereum Virtual Machine can understand what has been written.

Decentralized Applications(dapps)

The Ethereum Virtual Machine makes the process of creating decentralized applications much easier than ever before. Instead of having to build an entire blockchain for each new application, the EVM enables users to develop decentralized applications all on one platform.

Cryptokitties  is one of the most well known decentralized application (dapp) among many dapps developed so far. You can check out lots of interesting dapps at https://www.dapp.com/.  I have also developed a prototype dapp that I named it Kittychain Shop. In this virtual pet shop, the user can adopt a kitty, as shown in the figure below.

The Ethereum Architecture

Ethereum runs on a distributed public blockchain network. Each and every node connected to the Ethereum network helps to maintain and update the blockchain database. The nodes of the network run the EVM and execute the instructions according to the smart contracts.   Ethereum node runs the EVM in order to maintain consensus across the blockchain.

Ethereum peers achieve consensus via the proof of work algorithm, which is similar to bitcoin. However, they are planning to shift to the proof of stake algorithm in near future to improve scalability. The consensus gives Ethereum a high level of fault tolerance, ensures zero downtime, and makes data stored on the blockchain immutable and secure.

Like Bitcoin, Ethereum allows individuals to exchange cash without involving any middlemen like financial institutions and others. However, Ethereum is more than just cryptocurrency. Beyond financial applications, we can create decentralized applications where trust, security, and permanence are considered important. Among the potential applications are asset registries, voting, governance, Internet of things, supply chain management and more. 


Similar to Bitcoin, we can also carry out mining activity in Ethereum. However, In the Ethereum blockchain, instead of mining for bitcoin, miners work to earn Ether, the default currency of Ethereum. Beyond a tradeable cryptocurrency, Ether is also used by application developers to pay for transaction fees and services on the Ethereum network. For example, the user needs to pay for acquiring a crypto asset in a dapps marketplace using Ether.