blockchain – What is an Ethereum Client and What Clients Are Available

blockchainclientsconsensusnodes

What exactly is an Ethereum client? Is it a full network node that can post transactions to the blockchain (if that is the correct lingo?) or could it also be a light JS client that connects from a browser to a full node?

Could someone please shed some light on what clients there currently are and what roles they fulfill?

Best Answer

An 'Ethereum client' is just a term. It refers to any node able to parse and verify the blockchain, its smart contracts and everything related. It also allows you/provides interfaces to create transactions and mine blocks which is the key for any blockchain interaction.

Official reference implementations (CLI)

There are currently three reference implementations available, as you already highlighted:

Aleth - C++ client: https://github.com/ethereum/aleth. (It was formerly known as cpp-ethereum: https://github.com/ethereum/webthree-umbrella)
Geth - Golang client of the go-ethereum project: https://github.com/ethereum/go-ethereum
Trinity - Python client: https://github.com/ethereum/trinity

All clients should work the same, from the user's perspective. They provide the same interfaces and so on. For example, if you launch a DApp or the Ethereum Wallet or a DApp browser instance, it should not note any difference in communicating with the client.

Third party implementations (CLI)

Non-official clients implementing the yellow paper specification are:

Besu - (ex-Pantheon) Java client by PegaSys: https://github.com/hyperledger/besu
EthereumJ - Java client by the ether.camp team: https://github.com/ethereum/ethereumj
EthereumJS VM - Javascript Ethereum Virtual Machine: https://github.com/ethereumjs/ethereumjs-vm
Mana - Elixir by POA Network - https://github.com/mana-ethereum/mana
Minimal - Go client by umbracle - https://github.com/umbracle/minimal
Nethermind - C# / .NET by Nethermind
Parity Ethereum - Rust client by Parity Technologies : https://www.parity.io/ethereum/

Third party implementations (GUI)

Non-official clients with a graphical user interface are:

Etherwall, a Qt client like the good ol' bitcoin clients: https://github.com/almindor/etherwall

Deprecated or abandoned projects:

Official reference implementations (CLI):

Pyethapp - (pyethapp has been deprecated) Python client of the pyethereum project: https://github.com/ethereum/pyethapp

Graphical clients:

AlethZero (Alethzero has been deprecated): https://github.com/ethereum/alethzero
Mist Browser (Mist and Ethereum Wallet have been deprecated): https://github.com/ethereum/mist

Third Party clients:

ethereumH - Haskell client from consensys, but it's not developed anymore: https://github.com/jamshidh/ethereum-client-haskell (project has not been updated in a long time)
node-blockchain-server - simple Javascript server: https://github.com/ethereumjs/node-blockchain-server (project has not been updated in a long time)
ruby-ethereum - Ruby client: https://github.com/janx/ruby-ethereum (project has not been updated in a long time)

NOTE: all clients are listed in alphabetical order.

Yes it is possible you can connect to a remote node using `web3.js`

Adding web3

npm: $ npm install web3
bower: $ bower install web3
meteor: $meteor add ethereum:web3
vanilla: link the dist./web3.min.js

Then you need to create a web3 instance, setting a provider. To make sure you don't overwrite the already set provider when in mist, check first if the web3 is available:

if(typeof web3 !== 'undefined')
  web3 = new Web3(web3.currentProvider);
else
  // set the provider you want from Web3.providers
  web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));

Create a Wallet Address

Install ETH-lightwallet

npm install ETH-lightwallet

sample code to create a wallet.

// generate a new BIP32 12-word seed 
var secretSeed = lightwallet.keystore.generateRandomSeed();

// the seed is stored encrypted by a user-defined password 
var password = prompt('Enter password for encryption', 'password');
lightwallet.keystore.deriveKeyFromPassword(password, function (err, pwDerivedKey) {

var ks = new lightwallet.keystore(secretSeed, pwDerivedKey);

// generate five new address/private key pairs 
// the corresponding private keys are also encrypted 
ks.generateNewAddress(pwDerivedKey, 5);
var addr = ks.getAddresses();

// Create a custom passwordProvider to prompt the user to enter their 
// password whenever the hooked web3 provider issues a sendTransaction 
// call. 
ks.passwordProvider = function (callback) {
  var pw = prompt("Please enter password", "Password");
  callback(null, pw);
};

// Now set ks as transaction_signer in the hooked web3 provider 
// and you can start using web3 using the keys/addresses in ks! 
});

Best Answer

Official reference implementations (CLI)

Third party implementations (CLI)

Third party implementations (GUI)

Deprecated or abandoned projects:

Related Solutions

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[Ethereum] Is it possible to run the Ethereum Wallet with a remote Blockchain

Yes it is possible you can connect to a remote node using web3.js

Adding web3

Create a Wallet Address

Related Topic

Yes it is possible you can connect to a remote node using `web3.js`