In Bitcoin, Bob can post an address, and Alice can send to it without any interaction with Bob.
In Grin, Bob can post a slate S, Alice can interact with it, but Bob must finalize S before it hits the blockchain.
Is it possible for Bob to initially post additional information with S, so that Alice can finalize into an either-can-spend output without further assistance from Bob? Then, when Bob comes online at a later date, he can “claim” the payment by spending from it into an output he controls.
Alice could just hand Bob the blinding factor to one of her UTXOs.
The problem with an either-can-spend UTXO is that Bob needs to come online and actually spend it in order to ensure that Alice won’t spend it. I can’t think of a situation where this would be useful. If Bob trusts Alice enough to do this, why can he not simply trust that Alice will pay at a later date (i.e. when the slate finally has been responded to and finalized)?
Correct me if I’m wrong, but the scenario I described, Alice never needs to send information to Bob. It is one-way information flow: Bob -> Alice -> Blockchain, then later, Bob -> Blockchain.
I see. Good point. Do you have a scenario in mind where this would be useful?
I’m still brainstorming, and opening up the conversation to find out if it’s possible.