Published on: 2018-02-21T09:19:47+00:00
A recent discussion on the Lightning-dev mailing list has focused on the topic of proofs of payment in the context of the Lightning Network. The debate revolves around the use of Atomic Multipath Payments (AMP) and whether the current method of using a signed invoice and preimage is sufficient proof of payment.Some participants argue that the combination of a signed invoice and preimage is a reliable proof of payment. However, others disagree and suggest exploring stronger statements that can provide more robust proof. They propose leveraging ephemeral keys in onion packets or even using the onion as a witness to strengthen the proof of payment.The main concern raised by those advocating for stronger proof of payment is that it should demonstrate that the payee received the correct amount of funds, rather than simply proving that the payer sent the funds. They emphasize that if the payer can show that there was an arrangement that resulted in the payee receiving the correct amount, that should be considered as a valid payment. This includes scenarios where intermediaries are involved in the transaction.To address these concerns, suggestions have been made for new invoice formats. These formats would include an obligation for the signer to deliver certain information if all corresponding payment keys are provided. In cases of partial payment failure, the payer could sign a declaration specifying which transactions were canceled and which ones should be refunded. Importantly, these changes to the invoice format do not require modifications to the network protocol.While it is suggested that the court serves as the final point of settlement for invoices, it is acknowledged that the scripting language accepted by courts is flexible enough to enforce atomicity. This means that disputes and settlements can be handled cooperatively or through legal means.In conclusion, while the need for a proof of payment is recognized as important, the current method of using a signed invoice and preimage is deemed insufficient. Alternative methods that offer stronger statements should be explored. Additionally, proving that the payee received the correct amount of funds is prioritized over proving that the payer sent the funds. New invoice formats that provide proof of payment and facilitate dispute resolution through legal means have been suggested as potential solutions.
Updated on: 2023-07-31T19:46:27.065060+00:00