I would be fine with that, since segwit is widely deployed on the network already a lower activation threshold should be safe.
On Wed, May 24, 2017 at 12:02 PM, Wang Chun <1240...@gmail.com> wrote: > I think we should go for 75%, same Litecoin. As I have said before, 95% > threshold is too high even for unconventional soft forks. > >> 在 2017年5月24日，04:58，Andrew Chow via bitcoin-dev >> <bitcoin-dev@lists.linuxfoundation.org> 写道： >> >> Ah. I see now. It wasn't very clear to me that that is what will happen. >> >> Also, shouldn't the timeout date be set for before the BIP141 timeout? >> Otherwise this could lock in but not have enough time for Segwit to be >> locked in. >> >> >>> On 5/23/2017 4:42 PM, James Hilliard wrote: >>> That is incorrect, it is compatible with the current segwit >>> implementation because it triggers a mandatory signalling period that >>> will activate segwit on existing nodes. >>> >>> On Tue, May 23, 2017 at 4:39 PM, Andrew Chow via bitcoin-dev >>> <bitcoin-dev@lists.linuxfoundation.org> wrote: >>>> Hi James, >>>> >>>> From what I understand, this proposal is incompatible with the current >>>> segwit implementation with regards to the NODE_WITNESS service bit. I >>>> believe it could cause network partitioning if the service bit is not >>>> changed. >>>> >>>> Andrew >>>> >>>> >>>>> On 5/22/2017 6:40 PM, James Hilliard via bitcoin-dev wrote: >>>>> I would like to propose an implementation that accomplishes the first >>>>> part of the Barry Silbert proposal independently from the second: >>>>> >>>>> "Activate Segregated Witness at an 80% threshold, signaling at bit 4" >>>>> in a way that >>>>> >>>>> The goal here is to minimize chain split risk and network disruption >>>>> while maximizing backwards compatibility and still providing for rapid >>>>> activation of segwit at the 80% threshold using bit 4. >>>>> >>>>> By activating segwit immediately and separately from any HF we can >>>>> scale quickly without risking a rushed combined segwit+HF that would >>>>> almost certainly cause widespread issues. >>>>> >>>>> Draft proposal: >>>>> https://github.com/jameshilliard/bips/blob/bip-segsignal/bip-segsignal.mediawiki >>>>> >>>>> Proposal text: >>>>> <pre> >>>>> BIP: segsignal >>>>> Layer: Consensus (soft fork) >>>>> Title: Reduced signalling threshold activation of existing segwit >>>>> deployment >>>>> Author: James Hilliard <james.hillia...@gmail.com> >>>>> Status: Draft >>>>> Type: Standards Track >>>>> Created: 2017-05-22 >>>>> License: BSD-3-Clause >>>>> CC0-1.0 >>>>> </pre> >>>>> >>>>> ==Abstract== >>>>> >>>>> This document specifies a method to activate the existing BIP9 segwit >>>>> deployment with a majority hashpower less than 95%. >>>>> >>>>> ==Definitions== >>>>> >>>>> "existing segwit deployment" refer to the BIP9 "segwit" deployment >>>>> using bit 1, between November 15th 2016 and November 15th 2017 to >>>>> activate BIP141, BIP143 and BIP147. >>>>> >>>>> ==Motivation== >>>>> >>>>> Segwit increases the blocksize, fixes transaction malleability, and >>>>> makes scripting easier to upgrade as well as bringing many other >>>>> [https://bitcoincore.org/en/2016/01/26/segwit-benefits/ benefits]. >>>>> >>>>> This BIP provides a way for a simple majority of miners to coordinate >>>>> activation of the existing segwit deployment with less than 95% >>>>> hashpower. For a number of reasons a complete redeployment of segwit >>>>> is difficulty to do until the existing deployment expires. This is due >>>>> to 0.13.1+ having many segwit related features active already, >>>>> including all the P2P components, the new network service flag, the >>>>> witness-tx and block messages, compact blocks v2 and preferential >>>>> peering. A redeployment of segwit will need to redefine all these >>>>> things and doing so before expiry would greatly complicate testing. >>>>> >>>>> ==Specification== >>>>> >>>>> While this BIP is active, all blocks must set the nVersion header top >>>>> 3 bits to 001 together with bit field (1<<1) (according to the >>>>> existing segwit deployment). Blocks that do not signal as required >>>>> will be rejected. >>>>> >>>>> ==Deployment== >>>>> >>>>> This BIP will be deployed by a "version bits" with an 80%(this can be >>>>> adjusted if desired) activation threshold BIP9 with the name >>>>> "segsignal" and using bit 4. >>>>> >>>>> This BIP will have a start time of midnight June 1st, 2017 (epoch time >>>>> 1496275200) and timeout on midnight November 15th 2017 (epoch time >>>>> 1510704000). This BIP will cease to be active when segwit is >>>>> locked-in. >>>>> >>>>> === Reference implementation === >>>>> >>>>> <pre> >>>>> // Check if Segregated Witness is Locked In >>>>> bool IsWitnessLockedIn(const CBlockIndex* pindexPrev, const >>>>> Consensus::Params& params) >>>>> { >>>>> LOCK(cs_main); >>>>> return (VersionBitsState(pindexPrev, params, >>>>> Consensus::DEPLOYMENT_SEGWIT, versionbitscache) == >>>>> THRESHOLD_LOCKED_IN); >>>>> } >>>>> >>>>> // SEGSIGNAL mandatory segwit signalling. >>>>> if ( VersionBitsState(pindex->pprev, chainparams.GetConsensus(), >>>>> Consensus::DEPLOYMENT_SEGSIGNAL, versionbitscache) == THRESHOLD_ACTIVE >>>>> && >>>>> !IsWitnessLockedIn(pindex->pprev, chainparams.GetConsensus()) && >>>>> // Segwit is not locked in >>>>> !IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus()) ) // >>>>> and is not active. >>>>> { >>>>> bool fVersionBits = (pindex->nVersion & VERSIONBITS_TOP_MASK) == >>>>> VERSIONBITS_TOP_BITS; >>>>> bool fSegbit = (pindex->nVersion & >>>>> VersionBitsMask(chainparams.GetConsensus(), >>>>> Consensus::DEPLOYMENT_SEGWIT)) != 0; >>>>> if (!(fVersionBits && fSegbit)) { >>>>> return state.DoS(0, error("ConnectBlock(): relayed block must >>>>> signal for segwit, please upgrade"), REJECT_INVALID, "bad-no-segwit"); >>>>> } >>>>> } >>>>> </pre> >>>>> >>>>> https://github.com/bitcoin/bitcoin/compare/0.14...jameshilliard:segsignal-v0.14.1 >>>>> >>>>> ==Backwards Compatibility== >>>>> >>>>> This deployment is compatible with the existing "segwit" bit 1 >>>>> deployment scheduled between midnight November 15th, 2016 and midnight >>>>> November 15th, 2017. Miners will need to upgrade their nodes to >>>>> support segsignal otherwise they may build on top of an invalid block. >>>>> While this bip is active users should either upgrade to segsignal or >>>>> wait for additional confirmations when accepting payments. >>>>> >>>>> ==Rationale== >>>>> >>>>> Historically we have used IsSuperMajority() to activate soft forks >>>>> such as BIP66 which has a mandatory signalling requirement for miners >>>>> once activated, this ensures that miners are aware of new rules being >>>>> enforced. This technique can be leveraged to lower the signalling >>>>> threshold of a soft fork while it is in the process of being deployed >>>>> in a backwards compatible way. >>>>> >>>>> By orphaning non-signalling blocks during the BIP9 bit 1 "segwit" >>>>> deployment, this BIP can cause the existing "segwit" deployment to >>>>> activate without needing to release a new deployment. >>>>> >>>>> ==References== >>>>> >>>>> *[https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-March/013714.html >>>>> Mailing list discussion] >>>>> *[https://github.com/bitcoin/bitcoin/blob/v0.6.0/src/main.cpp#L1281-L1283 >>>>> P2SH flag day activation] >>>>> *[[bip-0009.mediawiki|BIP9 Version bits with timeout and delay]] >>>>> *[[bip-0016.mediawiki|BIP16 Pay to Script Hash]] >>>>> *[[bip-0141.mediawiki|BIP141 Segregated Witness (Consensus layer)]] >>>>> *[[bip-0143.mediawiki|BIP143 Transaction Signature Verification for >>>>> Version 0 Witness Program]] >>>>> *[[bip-0147.mediawiki|BIP147 Dealing with dummy stack element >>>>> malleability]] >>>>> *[[bip-0148.mediawiki|BIP148 Mandatory activation of segwit deployment]] >>>>> *[[bip-0149.mediawiki|BIP149 Segregated Witness (second deployment)]] >>>>> *[https://bitcoincore.org/en/2016/01/26/segwit-benefits/ Segwit benefits] >>>>> >>>>> ==Copyright== >>>>> >>>>> This document is dual licensed as BSD 3-clause, and Creative Commons >>>>> CC0 1.0 Universal. >>>>> _______________________________________________ >>>>> bitcoin-dev mailing list >>>>> bitcoin-dev@lists.linuxfoundation.org >>>>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >>>> _______________________________________________ >>>> bitcoin-dev mailing list >>>> bitcoin-dev@lists.linuxfoundation.org >>>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >> _______________________________________________ >> bitcoin-dev mailing list >> bitcoin-dev@lists.linuxfoundation.org >> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
