From rusty at rustcorp.com.au Wed Feb 7 23:21:43 2018 From: rusty at rustcorp.com.au (Rusty Russell) Date: Thu, 08 Feb 2018 09:51:43 +1030 Subject: [Lightning-dev] AMP: Atomic Multi-Path Payments over Lightning In-Reply-To: References: Message-ID: <87y3k41j3s.fsf@rustcorp.com.au> Olaoluwa Osuntokun writes: > Hi Y'all, > > A common question I've seen concerning Lightning is: "I have five $2 > channels, is it possible for me to *atomically* send $6 to fulfill a > payment?". The answer to this question is "yes", provided that the receiver This is awesome! I'm kicking myself for not proposing it :) Unfortunately, your proposal defines a way to make multipath donations, not multipath payments :( In other words, you've lost proof of payment, which IMHO is critical. Fortunately, this can be fairly trivially fixed when we go to scriptless scripts or other equivalent decorrelation mechanism, when I think this mechanism becomes extremely powerful. > - Potential fee savings for larger payments, contingent on there being a > super-linear component to routed fees. It's possible that with > modifications to the fee schedule, it's actually *cheaper* to send > payments over multiple flows rather than one giant flow. This is a stretch. I'd stick with the increased reliability/privacy arguments which are overwhelmingly compelling IMHO. If I have any important feedback on deeper reading (and after a sccond coffee), I'll send a separate email. Thanks! Rusty.