What happens if MPP is partially successful?
avatar for magic-loon-of-beauty (not signed)
22 months ago by

In MPP discussion https://stephanlivera.com/200/ during the 52:00 line of questions, at 53:55 "what are some of the constraints...?" Christian Decker mentions that receiver holds on to parts that succeeded. If the sender never finishes getting all parts across, what happens to the parts that did go thru?

ADD INCENTIVE   ADD COMMENTlink written 22 months ago by magic-loon-of-beauty (not signed)55k sats
avatar for magic-loon-of-beauty (not signed)
22 months ago by

There is no guarantee for atomicity, they assume incomplete payments will not be accepted by the receiver and they retry the payments that are not able to go through, possibly splitting them recursively until a minimum amount. I was not able to understand what happens in this case, since the receiver will still be able to accept most of the amount and the sender has no chance to call back the parts that went through. We need AMP. Source: https://lightning.engineering/posts/2020-05-07-mpp/

ADD COMMENTlink written 22 months ago by magic-loon-of-beauty (not signed)55k sats

Thanks for the thoughtful reply! Hey, your answer was anonymous so it's not eligible for the incentive. Does the site go far enough to communicate that only signed answers being able to get the incentive?

ADD REPLYlink written 21 months ago by sloppy-weasel-of-politeness1.2k sats
avatar for visionary-lively-jellyfish
17 months ago by
avatar for visionary-lively-jellyfish visionary-lively-jellyfish59k sats wrote:

Christian mentions that receivers hold on to parts that succeeded, but he really means to have them on-hold like the "hold" invoices that wait for a final confirmation from the receiver after the sender has a fully committed payment. Per the spec, the receiver should wait at least 60 secs for all other payments to come through. If they are not received in time, the final node must fail all the htlcs in the htlcset. However, if it fulfills any HTLCs in the htlset, it must fulfill ALL of them.

ADD COMMENTlink written 17 months ago by visionary-lively-jellyfish59k sats

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