Hacker News Reader

But do they send you the data first, or do you send them the payment first?

If they send you the data first, then why should you pay them? If you send them the payment first, then why should they send it?

I'm sure there's a piece I'm missing, but have I missed something obvious?

Data retrieval is broken into blocks so it's a repeated game with incentives to cooperate.

AFAIK Filecoin uses payment channels so you probably lock some money, retrieve data, then unlock the payment.

Incremental transfer seems like it should give an incentive to cooperate, but I don't think so?

If I pay you upfront for the first block, what stops you from then saying: actually I still want more money to start transfering the first block?

I doubt any of the protocols have an extortion response code.

Nothing, but then you pay a peer. That peer will likely send you the data so that you pay them for the second block, and so forth.