 So, let me start with the second question first. Is segregated witness necessary for lightning? Is there also something in segregated witness for sidechains? Yes, there are bits missing from the Bitcoin mainnet, which means that, at the moment, lightning network can be done, but in a very complicated way, that is not very efficient. So, segwit is necessary to do that, and there is a bit missing that is required for sidechains, which is you need to have a particular script operator that allows you to publish SPV proofs, a simple payment verification proof chains, basically, of merkle trees that point to specific transactions, in order to implement a two-way peg. That is a requirement. In order to do it smoothly, to do sidechains smoothly in Bitcoin, you need to upgrade the language. Now, segwit provides a very efficient scripting language upgrade mechanism that could make SPV proofs very easy to do. It has a script versioning number, so you could create a new version number, too. That version number could implement a sidechain SPV proof code, very simply with segwit. So, segwit is a prerequisite for a lot of things. You could do sidechains by replacing one of the existing opcodes, the same way that CheckLockTimeVerify was introduced. It took one of the unused opcodes and changed its meaning through a soft fork. But if you can get that kind of change through, why not just get segwit done, which would make things a lot easier? Alright, the second question is...