Published on: 2017-06-11T17:12:35+00:00
There has been an update on the prospects of BIP91 avoiding a BIP148 chain split. According to recent findings, the timing isn't as dire as previously suggested. However, unless there is solid progress on a plan, particularly with miner support, the split will still occur. There have been several refinements noted which could get BIP91 (or split protection, Segwit2x, etc.) deployed faster. These include shortening the lock-in window and reducing the 80% threshold. Additionally, BIP91 nodes could start signaling on bit 1 the moment bit 4 reaches lock-in, rather than waiting another period until it "activates". Combining these approaches, July 26th is an approximate hard deadline for over 50% of miners to be running BIP91 in order to prevent the split. This deadline is significantly less tight than the previous June 30th deadline. However, there are steps that need to be completed by that deadline. These include coordinating on a solution, implementing and testing it, convincing over 50% of miners to run it, and upgrading to the new software and begin signaling. A lot of convincing is still needed before miner support for any of these solutions reaches anything like 50%, except for Segwit2x, which has an additional handicap that it probably needs to include deployable hard fork code.Several dates have been provided, including August 1st as the date when BIP148 starts orphaning non-segwit blocks. It is expected that Segwit must activate by adjustment date #4 (~July 27) to avoid the BIP148 split. To avoid the BIP148 split, one of two things would have to happen: either 95% of hashrate start signaling bit 1 by ~June 30 or BIP91 is deployed and over 50% (80% or whatever) of hashrate is activated BIP91 miners by ~June 30. As of now, the split seems inevitable. It's expected that few parts of the ecosystem will join the fork, so disruption will be bearable.Jacob Eliosoff has been analyzing the expected interaction between James Hilliard's BIP91, splitprotection or Segwit2x and the BIP148 UASF. He concludes that it is unlikely that BIP91-type logic can activate segwit in time to avoid a BIP148 chain split, therefore ensuring the BIP148 split is as painless as possible. The deadline of BIP148 is already deployed and thus unlikely to be postponed, which means it starts orphaning non-segwit blocks on midnight (GMT) the morning of August 1. If Segwit activates on adjustment date #5 or later (August), it will be too late to avoid BIP148's split, which will have occurred the moment August began. To avoid the split, >50% of hashpower needs to be BIP91 miners, signaling bit 1 and orphaning non-BIP91 by June 30th.The expected interaction between James Hilliard's BIP91, Splitprotection and Segwit2x, which use variants of BIP91 activation, and the BIP148 UASF has been under discussion. It is unlikely that BIP91-type logic can activate segwit in time to avoid a BIP148 chain split, therefore ensuring the BIP148 split is as painless as possible is necessary. BIP148 starts orphaning non-segwit blocks on midnight (GMT) the morning of August 1. Segwit MUST activate by adj #4 (~July 27) to avoid BIP148's split, assuming compatibility with old BIP141 nodes. Therefore, >50% of hashpower needs to be BIP91 miners, signaling bit 1 and orphaning non-BIP91 by adj #2 (June 30). To avoid the BIP148 split, either 95% of hashrate must start signaling bit 1 by June 30 or BIP91 is deployed and >50% of hashrate is activated BIP91 miners by ~June 30. The BIP148 split is inevitable and few parts of the ecosystem are expected to join the fork, so disruption will be bearable.
Updated on: 2023-08-01T20:56:49.276258+00:00