奇偶校验网络的ethereumjs tx参数

我使用的是以太坊JS tx，下面的例子是rospten测试网：

const EthereumTx = require('ethereumjs-tx').Transaction;

const rawTx = {
            "from": sender,
            "nonce": "0x" + count.toString(16),
            "gasPrice": "0x003B9ACA00",
            "gasLimit": "0x250CA",
            "to": "0x3f84d0ca3529fbe8c2b...",
            "value": "0x0",
            "data": data,
            "chainId": 0x03
        };
const tx = new EthereumTx(rawTx, {'chain':'ropsten'});

对于奇偶校验专用网，我必须传递哪些参数

“chainId”：0x03

{'chain'：'ropsten'}