Published on: 2022-10-04T19:08:34+00:00
In an email thread on the bitcoin-dev mailing list, Eloy proposed a scheme that would enable recurring payments using a single offline interaction. The proposed scheme follows the structure described in BIP44 and involves the use of a "contact" level to represent a contact address for the recipient. By using Carol's contact address, Bob can generate multiple derived addresses for recurring payments without revealing any information on-chain.Eloy pointed out that while there are mentions of such a scheme, there is currently no framework to facilitate its usage and ensure interoperability between different implementations. To address this, Eloy proposed a BIP (Bitcoin Improvement Proposal) that would make it easier for developers to implement and users to utilize this scheme.Ruben responded to the proposal, acknowledging that it is an improvement over the current status quo. However, he noted that schemes like BIP47 and Silent Payments do not require any interaction with the sender, unlike this proposed scheme which requires a one-time interaction. This makes it less suitable for one-time donations.Ruben also raised concerns about how the "contact" level should be defined deterministically. If Bob defines it for Carol, it would be difficult to recover payments deterministically without backing up how it is defined. Additionally, Ruben highlighted the importance of considering the gap limit, suggesting that a low default gap limit should be defined for these extended public keys (xpubs) to avoid exponential blowup.Overall, the proposed scheme offers a positive solution to the issue of having to use a new address for every transaction, which can be inconvenient for making recurring payments. It provides privacy and allows for easy labeling of received payments. Furthermore, it gives Bob the advantage of choosing to send payments using multiple outputs. However, adjustments may be necessary for different address types on Bitcoin.
Updated on: 2023-08-02T07:35:46.646061+00:00