What did you mean when you use the term "BIG NODES?"

Good on ya for diving deep into this! Let's tackle those questions one by one:

1. No Lightning Transaction IDs: Unlike Bitcoin transactions, Lightning payments don't have transaction IDs because they're not broadcasted to the entire network. Instead, they're routed privately between parties involved in a channel.

2. Not Part of Blockchain: You're right! The Lightning Network is built on top of the Bitcoin blockchain but isn't part of it per se. It uses the underlying blockchain for opening and closing channels but most transactions happen off-chain.

3. Centralization Concerns: Some folks argue that Lightning could become centralized due to big nodes with lots of channels and liquidity (think major exchanges). But remember, anyone can run a node and open channels - so it's still quite decentralized at its core!

Hope that clears things up!