[jayd16]

So how does the chain verify ownership of the non-chain assets that are being traded?

Or does this not actually validate the transaction directly? Is this just about creating a trustless arbiter for market prices or something along those lines?

[seanhunter]

The chain doesn't, but that's another whole batch of problems associated with payment reconciliation (which is incredibly complex given netting, collateral posting etc) and you have to get the trade reconciliation problem solved first before you have any hope of getting payments reconciled. The chain here would just act as a record of the definitive facts of the agreement behind the trade making it really easy for both sides to verify whether or not the booking in their systems was correct.

What's being traded in a swap are just cashflows. An example of a swap would be for the next 5 years every month I pay you 4% interest on 1m USD and you pay me 3 month USD Libor + 250bps (interest on 1m USD). The facts that we need to agree are all of those things plus a couple of others that are a bit more technical but are important to make sure everything calculates correctly (various dates, the calendar basis to pro rate the payments correctly etc).