[Ethereum] One smart contract deployed on 2 nodes will have same address

I think this answer might be what you are looking for.

Is each Ethereum address shared by (theoretically) 2 ** 96 private keys?

There is no difference between testnet accounts and main-net accounts, you can move accounts between them, but of course transactions done in one net have not happen on the other.

Contracts live on the block chain, so they are unique to the current test/main network. if someone (speculating) creates a contract with the same address as a contract on another network, it doesn't mean anything and doesn't grant them any powers to the contract with the same address on the other network.

It's the contract owner account private key that is important (as the creator/owner).

All of these field have to be provided and should not be nil. There are generally 2 different types when encoding a transaction with RLP: 256-bit Number and a Bytes.

So if we have an empty data we would encode it as an empty bytes (e.g. 0x). In this case an empty string and an empty bytes are the same, as a string would be converted to bytes before RLP encoding.

For the address it is a little bit more tricky. It is defined as a Bytes that has a length of 20. Unless you have a creation transaction then it is an empty bytes.

You can find an example how this is implemented in the Kethereum repositors:

• RLP Encoding
• Type Mapping

You can find the more formal definition in the Ethereum Yellow Paper at the beginning of page 5.

A list of all fields that should be encoded in a Transaction can for example be found in EIP-1559 for the latest format.