Config local network

- Install Ganache
- Start Ganache and create new project by point to truffle-config.js file

Config Real network

- Register new account on infura.io
- Create new project
- Get project api and connection link: 
```
ROPSTEN_URL=https://ropsten.infura.io/v3/<your-api-key>
KOVAN_URL=https://kovan.infura.io/v3/<your-api-key>
RINKEBY_URL=https://rinkeby.infura.io/v3/<your-api-key>
MAINNET_URL=https://mainnet.infura.io/v3/<your-api-key>
```- Goto Truffle project, install node libs
```
npm install truffle-hdwallet-provider --save
npm install bip39 dotenv --save

# where
* bip39 – used to generate wallet mnemonic
* dotenv – simple way to read environment variable files
```
- Generate MNEMONIC words
```
node -e "console.log(require('bip39').generateMnemonic())"
```
- Create `.env` file, put MNEMONIC and <network>_URL to file
```
MNEMONIC=wallet mnemonic 12 words
ROPSTEN_URL=https://ropsten.infura.io/v3/<your-api-key>
KOVAN_URL=https://kovan.infura.io/v3/<your-api-key>
RINKEBY_URL=https://rinkeby.infura.io/v3/<your-api-key>
MAINNET_URL=https://mainnet.infura.io/v3/<your-api-key>
```
- Update truffle-config.js file
```
require('dotenv').config()
const HDWalletProvider = require('truffle-hdwallet-provider')
const MNEMONIC = process.env.MNEMONIC
const ROPSTEN_URL = process.env.ROPSTEN_URL
const KOVAN_URL = process.env.KOVAN_URL
const RINKEBY_URL = process.env.RINKEBY_URL
const MAINNET_URL = process.env.MAINNET_URL

module.exports = {
    // Uncommenting the defaults below
    // provides for an easier quick-start with Ganache.
    // You can also follow this format for other networks;
    // see <http://truffleframework.com/docs/advanced/configuration>
    // for more details on how to specify configuration options!
    contracts_build_directory: "../frontend/src/Contract/abi",
    networks: {
        development: {
            host: "127.0.0.1",
            port: 7545,
            network_id: "*"
        },
        test: {
            host: "127.0.0.1",
            port: 7545,
            network_id: "*"
        },
        ropsten: {
            provider: () => new HDWalletProvider(MNEMONIC, ROPSTEN_URL),
            network_id: 3
        },
        kovan: {
            provider: () => new HDWalletProvider(MNEMONIC, KOVAN_URL),
            network_id: 42…