Author: Ittay 2015-10-15 15:09:52
Published on: 2015-10-15T15:09:52+00:00
The email thread discusses two issues with the use of microblocks in Bitcoin, primarily that there is no way to punish people in case of double spend in a microblock that happens in a key block which reorganizes away the first transaction. The email suggests that microblocks would be very frequent if NG is to be used efficiently and such forks should occur at almost every key-block publication. A user should wait before accepting a transaction to make sure there was no key-block missed. The wait time is chosen according to the network propagation delay. The email also notes that the attacker has to win the key-block, have the to-be-inverted transaction in the previous epoch, and withhold his key-block for a while. Furthermore, the email discusses a point brought up by Greg Slepak on Twitter, which is that this model means users could no longer pick transactions in a mining pool which was set up in such a way. This tweak is dangerous as it means that the user can commit fraud at a much lower cost - their own pool reward, not the block's total reward. Additionally, the email suggests that taking reward compensation back by fraud proofs is not enough to fix the problems associated with double spending, as everyone has to wait for the "real" confirmations instead of the "possibly double-spend" confirmations. Fraud proof removes all the attacker's revenue, similar to how the attacker sacrifices an entire block for double spending in the current system.
Updated on: 2023-06-11T00:15:09.960944+00:00