Quote from: LoyceV on May 27, 2022, 09:05:05 AM

After reading it a few times, I think I'm starting to understand it. I would add another Con: something very simple suddenly becomes very complicated.

Once you get yourself familiar with how Elliptic-curve Diffie–Hellman key exchange scheme works, it becomes much easier to understand the idea of silent payments and other similar cryptographic privacy-enhancing methods of obscuring transaction processes in the bitcoin network. In a nutshell, all bitcoin users, who practice self-custody of their coins and therefore have direct access to private-public keypairs, can create a shared secret between each other using Diffie–Hellman algorithm. Alice and Bob exchange their public keys, multiply the new public key by the private key they control (elliptic curve multiplication, not an ordinary one), and use this new value in some function they both know about. In the case of silent payments, they create a new public key to which only one party will have a private key.

Quote from: Charles-Tim on May 27, 2022, 03:39:47 PM

There are differences between public key and address while referring to bitcoin. In the proposal, public key is referred to as address which would be very confusing because public key is different from address. Although, I get the fact that this type of payment is completely different from onchain payment.

This part is indeed confusing. I think when they say "payment address," they mean a public key encoded in a specific format to be distinguishable from regular non-silent public key.

Quote from: Charles-Tim on May 27, 2022, 03:39:47 PM

Even while using lightning network, onchain transactions are used to open and close a channel and yet the bitcoin would be credited to an address generated by standardized derivation path which this proposal do not include and yet indicating not including the derivation path as a benefit.

Your primary "silent public key" can be derived using standard derivation scheme, whereas all derived silent payments addresses constructed by senders will have a strong mathematical relationship with your public address and therefore are always deterministic. If you lose your private or public key, you can calculate them using your main seed, and than search again to find all connected silent addresses.