bitcoin-dev
Draft BIP for SNICKER
Posted on: October 20, 2019 00:29 UTC
A proposal called SNICKER (Simple Non-Interactive Coinjoin with Keys for Encryption Reused) has been introduced as an alternative type of CoinJoin by Adam Gibson.
The proposal has been shared in the form of a draft BIP. It is designed to break common chain-analysis assumptions further, indirectly benefiting the ecosystem as a whole, and is easy to implement for the "Receiver" role in a light wallet. The Receiver can find all his outputs and reconstruct all corresponding private keys deterministically from seed words and the blockchain. However, SNICKER breaks watch-only wallets as the scheme is fundamentally incompatible with them. Users would have to make a choice during wallet creation time whether they want to use xpubs or potentially participate in SNICKER coinjoins as a "Receiver". If SNICKER is not supported by the default choice, it is less likely to take off and, hence, less useful for the user; if xpubs are not supported by the default choice, existing user expectations are broken. It is unclear how the SNICKER scheme could be adjusted to fix this, as c
needs to be known exactly by the two coinjoin-participants and no one else.