📅 Original date posted:2021-05-16
📝 Original message:[sorry if I haven't replied to the other thread on this, I get swamped
by email and don't catch them all]
This solution is workable but it seems somewhat difficult to me at this time.
The clock might be implementable on a peer network level by requiring
inclusion of a transaction that was broadcast after a 9 minute delay.
Usually a 50% hashrate attack is needed to reverse a transaction in
bitcoin. With this change, this naively appears to become a 5%
hashrate attack, unless a second source of truth around time and order
is added, to verify proposed histories with.
A 5% hashrate attack is much harder here, because the users of mining
pools would be mining only 10% of the time, so compromising mining
pools would not be as useful.
Historically, hashrate has increased exponentially. This means that
the difficulty of performing an attack, whether it is 5% or 50%, is
still culturally infeasible because it is a multiplicative, rather
than an exponential, change.
If this approach were to be implemented, it could be important to
consider how many block confirmations people wait for to trust their
transaction is on the chain. A lone powerful miner could
intentionally fork the chain more easily by a factor of 10. They
would need to have hashrate that competes with a major pool to do so.
> How would you prevent miners to already compute the simpler difficulty problem directly after the block was found and publish their solution directly after minute 9? We would always have many people with a finished / competing solution.
Such a chain would have to wait a longer time to add further blocks
and would permanently be shorter.
> Your proposal won’t save any energy because it does nothing to decrease the budget available to mine a block (being the block reward).
You are assuming this budget is directly related to energy
expenditure, but if energy is only expended for 10% of the same
duration, this money must now be spent on hardware. The supply of
bitcoin hardware is limited.
In the long term, it won't be, so a 10% decrease is a stop-gap
measure. Additionally, in the long term, we will have quantum
computers and AI-designed cryptography algorithms, so things will be
different in a lot of other ways too.
Karl [ARCHIVE] /
npub10h…9xjf9
2023-06-07 22:53:26
in reply to nevent1q…v39f
Author Public Key
npub10hvdghlzknsxl8n9fhevm3hc6ppgkmnhjl0x7999hylnmcm3jursv9xjf9Published at
2023-06-07 22:53:26Event JSON
{
"id": "204dc00d54969303392db2941d810ff5a29717bb123a7e142fc6632030afe1f8",
"pubkey": "7dd8d45fe2b4e06f9e654df2cdc6f8d0428b6e7797de6f14a5b93f3de3719707",
"created_at": 1686178406,
"kind": 1,
"tags": [
[
"e",
"a28549d2211426df6f6b599aaeeca220945f4007b7b589085d2f10e0aa7a9cd1",
"",
"root"
],
[
"e",
"e5dfe5ef1544136b6aaf7243970802fd009206630682d966b4f3519cea6b0c9d",
"",
"reply"
],
[
"p",
"4137bb41a55a1c2c51d18f37f33cf0c29082422c56398d859ff1085f29eebd4b"
]
],
"content": "📅 Original date posted:2021-05-16\n📝 Original message:[sorry if I haven't replied to the other thread on this, I get swamped\nby email and don't catch them all]\n\nThis solution is workable but it seems somewhat difficult to me at this time.\n\nThe clock might be implementable on a peer network level by requiring\ninclusion of a transaction that was broadcast after a 9 minute delay.\n\nUsually a 50% hashrate attack is needed to reverse a transaction in\nbitcoin. With this change, this naively appears to become a 5%\nhashrate attack, unless a second source of truth around time and order\nis added, to verify proposed histories with.\n\nA 5% hashrate attack is much harder here, because the users of mining\npools would be mining only 10% of the time, so compromising mining\npools would not be as useful.\n\nHistorically, hashrate has increased exponentially. This means that\nthe difficulty of performing an attack, whether it is 5% or 50%, is\nstill culturally infeasible because it is a multiplicative, rather\nthan an exponential, change.\n\nIf this approach were to be implemented, it could be important to\nconsider how many block confirmations people wait for to trust their\ntransaction is on the chain. A lone powerful miner could\nintentionally fork the chain more easily by a factor of 10. They\nwould need to have hashrate that competes with a major pool to do so.\n\n\u003e How would you prevent miners to already compute the simpler difficulty problem directly after the block was found and publish their solution directly after minute 9? We would always have many people with a finished / competing solution.\n\nSuch a chain would have to wait a longer time to add further blocks\nand would permanently be shorter.\n\n\u003e Your proposal won’t save any energy because it does nothing to decrease the budget available to mine a block (being the block reward).\n\nYou are assuming this budget is directly related to energy\nexpenditure, but if energy is only expended for 10% of the same\nduration, this money must now be spent on hardware. The supply of\nbitcoin hardware is limited.\n\nIn the long term, it won't be, so a 10% decrease is a stop-gap\nmeasure. Additionally, in the long term, we will have quantum\ncomputers and AI-designed cryptography algorithms, so things will be\ndifferent in a lot of other ways too.",
"sig": "eb02d12900f6ad8c19374714d2d5dd28b556a6138488a398e42b1c02db68c6df5dfc0ca6fca247653bf274d5c5c9dcbc43fbfa820adfe8c42e04c110d53c8258"
}