Ocean Protocol contracts are deployed on multiple public networks. You can always find the most up-to-date deployment addresses for all individual contracts in the [address.json](https://github.com/oceanprotocol/contracts/blob/master/artifacts/address.json) artifact.
In each network, you’ll need ETH to pay for gas, and OCEAN for certain Ocean actions. Because the Ethereum mainnet is a network for production settings, ETH and OCEAN tokens have real value on there. The ETH and OCEAN tokens in each test network don’t have real value and are used for testing-purposes only. They can be obtained with _faucets_ to dole out ETH and OCEAN.
The Polygon Mainnet is another of the Ocean's production networks.
Polygon is an external network that you might not find as a predefined one inside your wallet. Thus you'll need to connect to it manually using the information below:
- ETH: [Faucet for Ropsten](https://faucet.dimensions.network/). You may find others by [searching](https://www.google.com/search?q=ropsten+ether+faucet&oq=ropsten+ether+faucet).
- OCEAN: [Faucet for Ropsten](https://faucet.ropsten.oceanprotocol.com/)
- ETH: [Faucet for Rinkeby](https://faucet.rinkeby.io/). You may find others by [searching](https://www.google.com/search?q=rinkeby+ether+faucet&oq=rinkeby+ether+faucet).
- OCEAN: [Faucet for Rinkeby](https://faucet.rinkeby.oceanprotocol.com/)
The most straightforward way for local-only development is to use [Barge](https://www.github.com/oceanprotocol/barge), which runs [Ganache](https://www.trufflesuite.com/ganache), Aquarius, and Provider. It is used extensively by the Ocean core devs (with Ganache or Rinkeby) and for automated integration testing.
<reponame="barge"></repo>
To connect to it from MetaMask, select the network called _Localhost 8545_.
Alternatively, you can run Ganache independently. Install it according to [the Ganache docs](https://www.trufflesuite.com/ganache). Then deploy Ocean contracts onto Ganache following [docs in Ocean contracts repo](https://www.github.com/oceanprotocol/contracts). Ganache is at the RPC URL [http://localhost:8545](http://localhost:8545).
- ETH: By default, Ganache creates several Ethereum accounts at launch, gives each some ETH, and makes their private keys available in the logs. You can also instruct Ganache to give ETH to specific Ethereum addresses.
- OCEAN: You can deploy an ERC20 token with label OCEAN. At a minimum, the token needs to be ERC20Detailed and ERC20Capped. You’ll see examples in the quickstarts for the Ocean JavaScript and Python drivers.
Some apps may need `network_id` and `chain_id`. Here's a [list of values for major Ethereum networks](https://medium.com/@piyopiyo/list-of-ethereums-major-network-and-chain-ids-2bc58e928508).
