The authors tested their algorithm on historic mempool data and found that it would’ve collected slightly more fees than Bitcoin Core’s existing algorithm in almost all recent blocks. This week’s newsletter describes a proposal for a standardized wallet label export format and includes our regular sections with summaries of recent questions and answers from the Bitcoin StackExchange, a list of new software releases and release candidates, and descriptions of notable changes to popular Bitcoin infrastructure software. Craig Raw noted several significant differences between what his proposed format is attempting to achieve and what SLIP15 seems to provide. A standardized export format could in theory allow two pieces of wallet software that used the same BIP32 account hierarchy to open each others’ backups and recover not just funds but all of the information the user manually entered about their transactions. This wouldn’t be any more effective at preventing fee sniping, but it would provide a good reason for regular wallets to set their nSequence values to the same values that are required for transactions in certain multisignature-based contract protocols, such as ideas for coinswaps and taproot-enabled LN. BOLT4 recommends that multiple channels between the same nodes should all use the same policy, but this doesn’t always happen, so this change tries to determine "the greatest common denominator of all policies" between the nodes.

Since the last release covered by Optech, support has been added for CPFP fee bumping, the ability to use additional features of LN URLs, plus multiple UI improvements. The receiver can then use the metadata as part of processing the payment, such as the originally proposed use of this information for enabling stateless invoices. When the receiver acknowledges that the money is available, the spender releases the information necessary for the receiver to claim the money. A new protocol version is not necessary for things to work; nodes using Erlay would not be incompatible with the existing protocol. Pieter Wuille points out the P2P network’s lack of transaction propagation guarantee as the reason for rebroadcasting being necessary and notes work done to remove rebroadcasting responsibilities from the wallet to the mempool. Discussion appeared to be ongoing as this summary was being written. Several developers replied with comments on Zhao’s summary and her proposals, youtu.be including additional or alternative proposals for changes that could be made. We solicited input from a number of services including BitGo, BRD, Conio, Electrum, and Gemini regarding their customer support burden from use of bech32 addresses. If a significant number of people use payjoin, this makes the common input heuristic used by block chain analysts much less reliable, improving privacy for even Bitcoin users who aren’t using payjoin.

For any of these options, any third-party looking at the block chain data sees only a single signature and no direct information about how many parties are involved, but each of the three key holders knows which two of the participants’ public keys were used to create the particular aggregated key that the spending signature matched, giving them private auditability. ● Unevicted signature: a signature for a public key corresponding to the shared public key of the whole group minus the public keys used in the eviction outputs. After 21 blocks, both satisfactions are available, but if a transaction with both A and B’s signatures is broadcast, a third party could remove A’s signature and still satisfy the other spending path. In the worst case scenario, if there is a flaw in the implementation, forgetting to verify the signature after signing could mean accidentally giving out an invalid signature. This would make the worst case pinning attack less expensive for the honest party to overcome. 1751 adds a blocking option to the payinvoice command which causes calls to payinvoice to block until the payment is completed. Until the payment eventually times out, each channel used to route the payment is unable to use those funds to route other user’s payments.

If more and more people in society begin to use blockchain technology, the networks will become jammed due to the limited number of transactions they can handle. Some signatures are still used, but the number is greatly reduced. When used, if the filter indicates that a block may contain transactions affecting the wallet, the full block of up to 4 megabytes is downloaded. A sane node must be valid and its script semantics must match its policy, be consensus-valid and standardness-compliant, only have non-malleable solutions, not mix timelock units (i.e. use both block height and time), and not have duplicate keys. However, many of these wallets also use P2SH-wrapped segwit addresses for receiving change sent from themselves to themselves. Because the transactions use less block weight, there’s more weight available for other transactions. Anti-fee-sniping attempts to equalize the advantages between honest miners who simply extend the block chain and dishonest miners who create chain forks in an attempt to steal fees from honest miners. For example, Alice’s node could announce that it would route payments up to 0.01 BTC from anyone who could prove they controlled at least 1.00 BTC. Miniscript expressions can be represented as trees of nodes, where each node represents a fragment.