Talk:Hardfork Wishlist: Difference between revisions
Created page with " ==Proposals which reduce security== "Difficulty adjustment should adapt to sudden hashrate loss" It's really hard to construct ''general'' proofs, but I believe that _all_ s..." |
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"Difficulty adjustment should adapt to sudden hashrate loss" | "Difficulty adjustment should adapt to sudden hashrate loss" | ||
It's really hard to construct ''general'' proofs, but I believe that _all_ such schemes substantially reduce the cost of performing forged chain attacks against isolated nodes. I | It's really hard to construct ''general'' proofs, but I believe that _all_ such schemes substantially reduce the cost of performing forged chain attacks against isolated nodes. I gave an argument of this here, assuming a particular decrease handling improvement: [https://bitcointalk.org/index.php?topic=46498.msg556137#msg556137] | ||
Beyond those problems schemes with symmetric difficulty creates non-linearities which make it profitable for miners as a group to game the system: e.g. turn off until it falls fast, then turn on until it catches back up. The current mostly linear system doesn't enable this even if the miners conspire. | |||
One of my concerns about this page is that it's lots of ideas sound just fantastic until you consider their costs, or sound great so long as you don't mind their particular costs. Because these changes must be adopted by consensus and because people evaluate costs differently it's hard to find things that win the cost/benefit analysis for almost everyone. | One of my concerns about this page is that it's lots of ideas sound just fantastic until you consider their costs, or sound great so long as you don't mind their particular costs. Because these changes must be adopted by consensus and because people evaluate costs differently it's hard to find things that win the cost/benefit analysis for almost everyone. | ||
Revision as of 20:01, 4 January 2012
Proposals which reduce security
"Difficulty adjustment should adapt to sudden hashrate loss"
It's really hard to construct general proofs, but I believe that _all_ such schemes substantially reduce the cost of performing forged chain attacks against isolated nodes. I gave an argument of this here, assuming a particular decrease handling improvement: [1]
Beyond those problems schemes with symmetric difficulty creates non-linearities which make it profitable for miners as a group to game the system: e.g. turn off until it falls fast, then turn on until it catches back up. The current mostly linear system doesn't enable this even if the miners conspire.
One of my concerns about this page is that it's lots of ideas sound just fantastic until you consider their costs, or sound great so long as you don't mind their particular costs. Because these changes must be adopted by consensus and because people evaluate costs differently it's hard to find things that win the cost/benefit analysis for almost everyone.
In my opinion, the drop risk is inconsequential: Having the average txn time go to 20 minutes for a month isn't really a big deal... and if there is a bigger drop then the slow txn processing time will be the least of our problems. The costs here are not speculative, altchains with "improved" difficulty adjustments have been exploited several times. The benefit is purely speculative and primarily matters only if bitcoin is already failing.
Perhaps we should change the page to tabular layout so that we can link to for and against arguments for features where ones exist? --Gmaxwell 19:59, 4 January 2012 (GMT)