Except that an entity with 51% power could conceivably cause damage in ways that would be hard to figure out (say, but obfuscating the blockchain—obfuscations could easily get lost in the daily chaos of bitcoin trade). The only safe course of action is to assume that once an entity has gained 51% power, all further blocks are ‘tainted’, and roll back blocks until before the entity had 51% power. But this would be a huge nuisance for miners, users, and exchanges alike.
This is completely false and I can’t understand how you could have acquired this impression.
What do you mean by ‘obfuscating’?
A 50+% entity cannot cause permanent damage to the blockchain; they cannot steal coins; they cannot generate coins that weren’t supposed to exist; the ONLY extra powers they have are
(1) to suppress transactions that would otherwise have occurred, and
(2) to prevent other miners from mining.
Neither of these transactions has any permanent effect on the blockchain after the attack stops, except for the omission of transactions that would otherwise have been present (which, assuming they were organic transactions by real users, will be automatically resubmitted until they’re included in a subsequent block.)
Except that an entity with 51% power could conceivably cause damage in ways that would be hard to figure out (say, but obfuscating the blockchain—obfuscations could easily get lost in the daily chaos of bitcoin trade). The only safe course of action is to assume that once an entity has gained 51% power, all further blocks are ‘tainted’, and roll back blocks until before the entity had 51% power. But this would be a huge nuisance for miners, users, and exchanges alike.
This is completely false and I can’t understand how you could have acquired this impression.
What do you mean by ‘obfuscating’?
A 50+% entity cannot cause permanent damage to the blockchain; they cannot steal coins; they cannot generate coins that weren’t supposed to exist; the ONLY extra powers they have are
(1) to suppress transactions that would otherwise have occurred, and (2) to prevent other miners from mining.
Neither of these transactions has any permanent effect on the blockchain after the attack stops, except for the omission of transactions that would otherwise have been present (which, assuming they were organic transactions by real users, will be automatically resubmitted until they’re included in a subsequent block.)
While I don’t think bitcoin would completely crash, double spending could be an serious issue.