Author: Peter Todd 2017-02-24 01:09:43
Published on: 2017-02-24T01:09:43+00:00
The email conversation between Bram Cohen and Peter Todd on 23rd February 2017, discussed the benefits of unspent transaction output (UTXO) commitments. Peter Todd proposed committing to the state of all transaction outputs with a merkle tree structure, including the outpoint, spent/unspent status, scriptPubKey, and nValue. He suggested committing to an insertion-ordered list indexed by txout # instead of a balanced version of the TXO set. Todd stated that full nodes could independently update and recalculate the UTXO set as part of their validation process, but it is not possible for a balanced version of the TXO set because it is too big. Cohen responded by saying that MMRs looked redundant with the actual blockchain history, but he agreed that making a compact proof that something is still in the UTXO set is the whole point of UTXO commitments. Cohen also argued that relying on proofs as a crutch for using the full TXO set would exacerbate the problem of miners doing SPV mining and increase the bandwidth a full validating node had to use. Todd further clarified that his proposal was independent of MMRs and needed to be argued on its own merits.
Updated on: 2023-06-11T21:40:22.615708+00:00