Ethereum Test network

Ethereum has three test network for developer to develop and to do testing, namely ROPSTEN, KOVAN and RINKEBY.

Ropsten

• PoW testnet
• Network id: 3
• Block time: sub-30 seconds
• Commands:
• geth --testnet or geth --networkid 3
• parity --chain ropsten
• Explorer https://ropsten.etherscan.io/
• Github https://github.com/ethereum/ropsten

History:

• Started in November 2016. Named after a subway station in Stockholm.
• Was DoS attacked in February 2017 which made synching slow and made clients consume a lot of disk space.
• Was revived in March 2017 and became usable again.

Pros:

• Best reproduces the current production environment, i.e. system and network conditions on the live Ethereum mainnet, because it’s PoW net.
• Can be used with both geth and parity.
• Ether can be mined. Or requested from a faucet:
• https://faucet.metamask.io/
• http://faucet.ropsten.be:3001
• https://faucet.bitfwd.xyz/
• What public test-networks and faucets exist?

Cons:

• Not immune to spam attacks. Because of this it’s less stable.

Kovan

• PoA testnet started by the Parity team
• Network id: 42
• Block time: 4 seconds
• Command: parity --chain kovan
• Explorer https://kovan.etherscan.io/
• Github https://github.com/kovan-testnet/proposal

History:

• Started in March 2017. Named after a subway station in Singapore.

Pros:

• Immune to spam attacks (as Ether supply is controlled by trusted parties)

Cons:

• Not supported in geth.
• Doesn’t fully reproduce the current production environment as it uses PoA.
• Ether can’t be mined. It has to be requested from the faucet.

Rinkeby

• PoA testnet started by the Ethereum team. Uses Clique PoA consensus protocol.
• Network id: 4
• Block time: 15 seconds
• Command: geth --rinkeby or geth --networkid 4
• Explorer https://rinkeby.etherscan.io/
• Github https://github.com/ethereum/EIPs/issues/225
• Website https://www.rinkeby.io

History:

• Started in April 2017. Named after a metro station in Stockholm.

Pros:

• Immune to spam attacks (as Ether supply is controlled by trusted parties)

Cons:

• Supported by geth only
• Doesn’t fully reproduce the current production environment as it uses PoA.
• Ether can’t be mined. It has to be requested from a faucet:
• https://faucet.rinkeby.io/

Görli

Work on the testnet began at the ETHBerlin hackathon in early September, when Parity’s Afri Scohedon banded together with Chainsafe Systems in a bid to create a “next-generation public Ethereum test network”.

• PoA testnet
• Explorer https://goerli.etherscan.io/
• Github https://github.com/goerli/testnet
• Website https://www.rinkeby.io
• Faucet: https://goerli-faucet.slock.it/

Other :

• 0: Olympic, Ethereum public pre-release testnet
• 1: Frontier, Homestead, Metropolis, the Ethereum public main network
• 1: Classic, the (un)forked public Ethereum Classic main network, chain ID 61
• 1: Expanse, an alternative Ethereum implementation, chain ID 2
• 2: Morden, the public Ethereum testnet, now Ethereum Classic testnet
• 3: Ropsten, the public cross-client Ethereum testnet
• 4: Rinkeby, the public Geth PoA testnet
• 8: Ubiq, the public Gubiq main network with flux difficulty chain ID 8
• 42: Kovan, the public Parity PoA testnet
• 77: Sokol, the public POA Network testnet
• 99: Core, the public POA Network main network
• 100: xDai, the public MakerDAO/POA Network main network
• 401697: Tobalaba, the public Energy Web Foundation testnet
• 7762959: Musicoin, the music blockchain
• 61717561: Aquachain, ASIC resistant chain
• [Other]: Could indicate that your connected to a local development test network.

Source : https://ethereum.stackexchange.com/questions/27048/comparison-of-the-different-testnets/30072#30072

https://ethereum.stackexchange.com/questions/17051/how-to-select-a-network-id-or-is-there-a-list-of-network-ids/17101#17101