📅 Original date posted:2017-07-04
📝 Original message:On Tue, Jul 04, 2017 at 09:30:26PM -0400, 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).
If there are miners that start doing 1 second timestamp advances, it would be
simpler (and probably safer) to require a minimum block time spacing of say
30 seconds or 1 minute, and orphan blocks that are too close in time and more
than say an hour behind real-time.
I cannot picture any realistic scenario in which an attempt to block activation
in this way is in anything other than a very expensive temper tantrum for any
miners foolish enough to attempt it.
It *might* be a delay tactic as a 'nuclear option' attack vector for a mining
cabal to run up the difficulty so high as to make it impractical to mine any
new blocks after the adjustment, but there are plenty of altcoins that have
hardforked and gotten along just fine after the same kind of thing due to
profit-switching pools.
> 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 at lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
Troy Benjegerdes [ARCHIVE] /
npub1m6…rdjn5
2023-06-07 20:03:55
in reply to nevent1q…m048
Author Public Key
npub1m6p5kgcd428x6pxyfege98zjmlwrdhp0gyz6pdnsvrvalscddnxqurdjn5Published at
2023-06-07 20:03:55Event JSON
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"content": "📅 Original date posted:2017-07-04\n📝 Original message:On Tue, Jul 04, 2017 at 09:30:26PM -0400, shaolinfry via bitcoin-dev wrote:\n\u003e 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).\n\nIf there are miners that start doing 1 second timestamp advances, it would be\nsimpler (and probably safer) to require a minimum block time spacing of say\n30 seconds or 1 minute, and orphan blocks that are too close in time and more\nthan say an hour behind real-time.\n\nI cannot picture any realistic scenario in which an attempt to block activation\nin this way is in anything other than a very expensive temper tantrum for any\nminers foolish enough to attempt it.\n\nIt *might* be a delay tactic as a 'nuclear option' attack vector for a mining\ncabal to run up the difficulty so high as to make it impractical to mine any\nnew blocks after the adjustment, but there are plenty of altcoins that have\nhardforked and gotten along just fine after the same kind of thing due to\nprofit-switching pools.\n\n\n\u003e 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.\n\u003e 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.\n\n\u003e _______________________________________________\n\u003e bitcoin-dev mailing list\n\u003e bitcoin-dev at lists.linuxfoundation.org\n\u003e https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev",
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