Some folks have expressed the opinion {that a} profitable double-spend assault would invalidate Bitcoin as a expertise, and thus undermine the worth of all Bitcoins (together with the attacker’s), making an assault an unwinnable state of affairs.
That doesn’t appear affordable to me. Now we have seen doublespends on different networks and people networks persevering with to function later. It could absolutely influence the worth of Bitcoin, however it appears absurd that the brand new worth would instantly be zero. Most individuals wouldn’t even catch on to the occasions for hours or days.
My thought is that if my node detected a big re-org and double spend inside that re-org, I might not settle for fee related to the double spender. If his id was publicly identified, no one would settle for his Bitcoins as a result of they know they’re liable to be double spent. If his id was not publicly identified, his Bitcoins are nonetheless tied to the assault, and no one ought to simply accept them for a similar motive.
Relying on how the attacker chosen transactions of their blocks, there is perhaps one thing on the order of 24 000 transactions in six blocks that turn into unconfirmed if the attacker merely doesn’t embody any transactions within the alternative blocks. Whereas it might be attainable to discover a single or few transactions with excessive worth that resolve in a different way, it might be fuzzy and non-obvious for a quantity extra. I’m not satisfied it is a sensible method.
However on the opposite facet of the coin… Now, I do know for a reality that every one different Bitcoins not related to the attacker can’t be double-spent, as a result of by definition just one entity can have greater than 50% of the hash energy at a given time.
Assuming that the attacker solely consists of their very own transactions, the senders of ~24 000 transactions could be within the place of having the ability to reissue their very own transactions. It’s not clear in any respect to me why somebody attacking the blockchain offers extra confidence to the actions of different customers.
Would this create a state of affairs the place the attacker has successfully burnt his personal cash whereas concurrently rising the trustworthiness of all different cash?
No, by no means.
Or mentioned one other approach: is it legitimate that we would not have to imagine a 51% assault would undermine your complete community’s worth to conclude that it could nonetheless be self-undermining for the attacker?
No, by all probability, the attacker would instantly commerce out of Bitcoin in the event that they had been fearful concerning the assault severely impacting Bitcoin’s worth. They won’t be capable of commerce a number of the cash that had been concerned within the assault, however they might brief Bitcoin in a future commerce or at the very least commerce all their different Bitcoin holdings. The attacker might then even commerce again in on the dip attributable to their assault’s injury to Bitcoin’s worth and earn extra worth on the restoration. I don’t assume this argument stands as much as scrutiny.
Some folks have expressed the opinion {that a} profitable double-spend assault would invalidate Bitcoin as a expertise, and thus undermine the worth of all Bitcoins (together with the attacker’s), making an assault an unwinnable state of affairs.
That doesn’t appear affordable to me. Now we have seen doublespends on different networks and people networks persevering with to function later. It could absolutely influence the worth of Bitcoin, however it appears absurd that the brand new worth would instantly be zero. Most individuals wouldn’t even catch on to the occasions for hours or days.
My thought is that if my node detected a big re-org and double spend inside that re-org, I might not settle for fee related to the double spender. If his id was publicly identified, no one would settle for his Bitcoins as a result of they know they’re liable to be double spent. If his id was not publicly identified, his Bitcoins are nonetheless tied to the assault, and no one ought to simply accept them for a similar motive.
Relying on how the attacker chosen transactions of their blocks, there is perhaps one thing on the order of 24 000 transactions in six blocks that turn into unconfirmed if the attacker merely doesn’t embody any transactions within the alternative blocks. Whereas it might be attainable to discover a single or few transactions with excessive worth that resolve in a different way, it might be fuzzy and non-obvious for a quantity extra. I’m not satisfied it is a sensible method.
However on the opposite facet of the coin… Now, I do know for a reality that every one different Bitcoins not related to the attacker can’t be double-spent, as a result of by definition just one entity can have greater than 50% of the hash energy at a given time.
Assuming that the attacker solely consists of their very own transactions, the senders of ~24 000 transactions could be within the place of having the ability to reissue their very own transactions. It’s not clear in any respect to me why somebody attacking the blockchain offers extra confidence to the actions of different customers.
Would this create a state of affairs the place the attacker has successfully burnt his personal cash whereas concurrently rising the trustworthiness of all different cash?
No, by no means.
Or mentioned one other approach: is it legitimate that we would not have to imagine a 51% assault would undermine your complete community’s worth to conclude that it could nonetheless be self-undermining for the attacker?
No, by all probability, the attacker would instantly commerce out of Bitcoin in the event that they had been fearful concerning the assault severely impacting Bitcoin’s worth. They won’t be capable of commerce a number of the cash that had been concerned within the assault, however they might brief Bitcoin in a future commerce or at the very least commerce all their different Bitcoin holdings. The attacker might then even commerce again in on the dip attributable to their assault’s injury to Bitcoin’s worth and earn extra worth on the restoration. I don’t assume this argument stands as much as scrutiny.
