delvingbitcoin
Contract-level Relative Timelocks (or, let's talk about ancestry proofs and singletons)
Posted on: January 6, 2025 13:48 UTC
The discussion revolves around the concept of utilizing a singleton, essentially an NFT, to represent the identity of a contract.
This approach is aimed at achieving a constant size proof of ancestry, which is significant because it allows for recursive bounded introspection within the system. By implementing this method, every update transaction in addition to the settlement transaction would require introspection logic. This introspection involves knowing about the initial kickoff transaction ID (txid) and making assertions based on the update step.
An interesting point raised is the implication of this system on the overhead for submitted updates. Specifically, this overhead would be the responsibility of the submitter rather than falling on the honest participant during the settlement time. This mechanism is considered beneficial for ensuring the safety of relay and consensus processes by establishing a clear boundary on the size of the witness-stripped update transactions.
Furthermore, a practical construction suggestion for implementing this concept involves creating a 1-in/2-out transaction where the first output holds the singleton, and the second output is directed to a pay-to-anchor address. The spender of this pay-to-anchor address would then have the capability to utilize the singleton. This construction is viewed as a sensible approach to integrating the discussed concepts into a functional system.