It's not pointless: it's a wake-up call for miners asleep "at the wheel", to ensure they upgrade in time. Not having a mandatory signal turned out to be a serious bug in BIP 9, and one which is fixed in BIP 148 (and remains a problem for BIP 149 as-is). Additionally, it makes the activation decisive and unambiguous: once the lock-in period is complete, there remains no question as to what the correct protocol rules are.
It also enables deploying softforks as a MASF, and only upgrading them to UASF on an as-needed basis. Luke On Wednesday 05 July 2017 4:00:38 AM shaolinfry wrote: > Luke, > I previously explored an extra state to require signalling before > activation in an earlier draft of BIP8, but the overall impression I got > was that gratuitous orphaning was undesirable, so I dropped it. I > understand the motivation behind it (to ensure miners are upgraded), but > it's also rather pointless when miners can just fake signal. A properly > constructed soft fork is generally such that miners have to deliberately > do something invalid - they cannot be tricked into it... and miners can > always chose to do something invalid anyway. > > > -------- Original Message -------- > > From: l...@dashjr.org > > To: bitcoin-dev@lists.linuxfoundation.org, shaolinfry > > <shaolin...@protonmail.ch> I"ve already opened a PR almost 2 weeks ago > > to do this and fix the other issues BIP 9 has. > > https://github.com/bitcoin/bips/pull/550 > > It just needs your ACK to merge. > > > > On Wednesday 05 July 2017 1:30:26 AM shaolinfry via bitcoin-dev wrote: > >> Some people have criticized BIP9"s blocktime based thresholds arguing > >> they are confusing (the first retarget after threshold). It is also > >> vulnerable to miners fiddling with timestamps in a way that could > >> prevent or delay activation - for example by only advancing the block > >> timestamp by 1 second you would never meet the threshold (although this > >> would come a the penalty of hiking the difficulty dramatically). On the > >> other hand, the exact date of a height based thresholds is hard to > >> predict a long time in advance due to difficulty fluctuations. However, > >> there is certainty at a given block height and it"s easy to monitor. If > >> there is sufficient interest, I would be happy to amend BIP8 to be > >> height based. I originally omitted height based thresholds in the > >> interests of simplicity of review - but now that the proposal has been > >> widely reviewed it would be a trivial amendment. _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev