Author: Tao Effect 2017-06-07 05:20:52
Published on: 2017-06-07T05:20:52+00:00
In a recent email thread on bitcoin-dev, James Hilliard proposed a splitprotection soft fork to prevent a chain split ahead of the Aug 1st BIP148 activation date. This BIP allows miners to coordinate activation of the existing segwit deployment with a simple miner majority of 65% over a 504 block interval rather than a higher percentage. All blocks must set the nVersion header top 3 bits to 001 together with bit field (1> existing segwit deployment). Blocks that do not signal as required will be rejected. The proposed calendar for the SegWit2x agreement was too slow to activate SegWit mandatory signalling ahead of BIP148 using BIP91. Splitprotection is essentially BIP91 but using BIP8 instead of BIP9 with a lower activation threshold and immediate mandatory signalling lock-in. It gives Core more leverage in negotiations. If they don't activate with 80%, Core can release another BIP to reduce it to 75%. Each threshold reduction makes it both more likely to succeed, but also increases the likelihood of harm to the ecosystem.However, there are concerns that a 65% threshold may be too low and can allow a "surprise miner attack" whereby miners are kept offline before the deadline, and brought online immediately after, creating potential havoc. It is important to note that the primary goal of this BIP is to reduce the chance of an extended chain split as much as possible.While this bip is active users should either upgrade to splitprotection or wait for additional confirmations when accepting payments. The proposal is compatible with the existing "segwit" bit 1 deployment scheduled between midnight November 15th, 2016 and midnight November 15th, 2017. It is also compatible with the existing BIP148 deployment. Miners will need to upgrade their nodes to support splitprotection otherwise they may build on top of an invalid block.
Updated on: 2023-06-12T01:55:57.676686+00:00