Releases, security notices and protocol work from the people who build Bitcoin software.
121 publications
Wallet sends that hit the limit on unconfirmed chains no longer return an RPC error in Bitcoin Core 0.13.2. They report success, and mempool insertion is retried at rebroadcast with no restart needed. Fee estimates for a 1-block target are disabled, and handling of invalid compact blocks is fixed.
Bitcoin Core
Wrapping segwit in P2SH carries the biggest byte cost: 19% extra for P2WSH/P2SH and 11% for P2WPKH/P2SH on a 180-byte transaction, by Bitcoin Core's tally of what BIP141 would bring. Validation needs about five more SHA256 hashes per transaction. Bugs, larger blocks and lower fees are weighed as risks, and the authors take no position on activation.
Bitcoin Core
Miners get code to signal for the segwit soft fork in Bitcoin Core 0.13.1, with signalling open from 15 November 2016 at the start of the next retarget period. Lock-in takes 95% of blocks in a 2,016-block period, and activation comes one period later. Wallets stay compatible, so nobody but miners may need to act.
Bitcoin Core
Segwit needs two groups on board: miners signaling bit 1 in 95% of blocks over a retarget period, and enough full nodes running Bitcoin Core 0.13.1 or a compatible implementation. Signaling opens at the first retarget that falls on or after 15 November 2016. Separate steps cover miners, node operators, wallet users and developers, including those who choose not to upgrade.
Bitcoin Core
Segwit code lands in Bitcoin Core 0.13.0 but stays inactive on mainnet; using it there will take a later version, expected to be 0.13.1. Compact block relay (BIP152) trims bandwidth spikes, and new wallets use BIP32 HD keys, so one backup covers every future private key. Linux ARM builds also join the official downloads.
Bitcoin Core
The consensus and peer-to-peer changes behind segwit touch 1,486 lines of code, with 3,338 more lines of tests. Testing ran from Pieter Wuille's Elements sidechain version in 2015 through segnet to Bitcoin's regular testnet in May 2016. Schnorr signatures and MAST are named as later upgrades segwit would make easier.
Bitcoin Core
Signaling for the CSV soft fork starts at midnight on May 1st, 2016 with Bitcoin Core 0.12.1, the first deployment through BIP9 version bits. It covers BIP68, BIP112 and BIP113; OP_CHECKSEQUENCEVERIFY lets coins be frozen for a set time after confirmation, which Lightning Network will depend on. The p2p alert system now defaults to off.
Bitcoin Core
Marco Falke is Bitcoin Core's new Testing & QA maintainer, Wladimir van der Laan announced. He takes charge of merging test framework pull requests, a natural step after a year spent on unit tests, coverage and reviewing other contributors' work.
Bitcoin Core
Security issues and new releases now have their own Bitcoin Core announcement list, opt-in and announcement-only. Users had asked for a way to receive only the critical notices, and the project expects very low volume.
Bitcoin Core
A 16x16 Sudoku solution sold for 0.10 BTC in the first successful Zero-Knowledge Contingent Payment on Bitcoin, demonstrated live at Financial Cryptography 2016 in Barbados. Sean Bowe of the Zcash team was the seller and did almost all the engineering. Under the protocol, the data changes hands only if payment is made, with no third party to arbitrate.
Bitcoin Core
OpenSSL is out of signature checks in Bitcoin Core 0.12.0, replaced by libsecp256k1, which cuts reindexing and new block validation to under half their old time. Mempools get a 300 MB default cap, closing a way attackers could crash low-RAM nodes. Also new: opt-in Replace-by-Fee (BIP 125) and -maxuploadtarget for limiting upload traffic.
Bitcoin Core
Bitcoin Core says the site that first hosted the Bitcoin paper is not affiliated with the project, which has its own official website. Development runs on IRC, GitHub and the bitcoin-dev mailing list. The project takes no responsibility for other forums and asks community members not to brigade or launch denial-of-service attacks.
Bitcoin Core
Third-party malleability ends for transactions whose inputs are all segwit spends, because signatures move to a witness that no longer feeds the txid. Wallet authors and the Lightning Network both gain from that. Signature hashing also turns linear, with each byte hashed at most twice; a single block has taken 25 seconds to validate under the old scheme.
Bitcoin Core
Developers can now test Segregated Witness on its own network by compiling the segwit branch and adding -segnet to bitcoind and bitcoin-cli. Ledger, Trezor, Electrum and Bitgo have said they will support segwit, while mSIGNA and Green Address offer early previews.
Bitcoin Core
A video maps 2015 commit activity in the Bitcoin Core repository, a year with 2 major versions, 5 maintenance releases and two activated soft forks: BIP66 and BIP65, the latter adding CHECKLOCKTIMEVERIFY. Reviewers, testers and translators don't show up in commit data, the project points out.
Bitcoin Core
Consensus rules are not for the Bitcoin Core team to decide, its contributors say; users decide by choosing which software to run, and that is why it ships without auto-update. They favour soft forks, reserving hard forks for rare cases with near-universal agreement, and see additional layers on top of the protocol as the route to extremely high scale.
Bitcoin Core
Blocks under segwit's new cost limit can reach just under 4 MB, but Anthony Towns's calculations put a block of single-signature P2PKH transactions near 1.6 MB and one of 2-of-2 multisig near 2.0 MB. The FAQ's tentative schedule has segwit deploying in 0.13.1 in October 2016, with weak blocks, IBLT or Lightning following in 2017.
Bitcoin Core
Signing on to the capacity roadmap, 57 people including Pieter Wuille, Gregory Maxwell and Wladimir J. van der Laan call it the best continuation of their scalability work within Bitcoin Core. The list stays open to further signatures.
Bitcoin Core
Pieter Wuille presents Segregated Witness at length in a video posted by Bitcoin Core, with no written notes alongside it.
Bitcoin Core
Gregory Maxwell's roadmap, sent to the bitcoin-dev mailing list as Scaling Bitcoin Hong Kong wrapped up, builds on libsecp256k1, BIP9 versionbits and Pieter Wuille's Segregated Witness. He reports ConnectTip running 7x faster in 0.12, and describes segwit as a soft fork that takes signatures outside the current blocksize limit, amounting to a 4MB increase at worst.
Bitcoin Core
