Decreasing Security Threshold Against Double Spend Attack in Networks with Slow Synchronization

Blockchain Technologies: Probability of Double-Spend Attack on a Proof-of-Stake Consensus

“…The work [ 9 ] generalized the results obtained in [ 8 ]. In this work, for the first time (in model with continuous time, without simplified assumptions about discrete timeslots), the author obtained and strictly proved the expression that gives the value of double-spend attack probability in dependence on network parameters, including network synchronization time.…”

“…However, in PoW, the synchronization time plays a very important role. As shown in [ 9 , 27 ], the security threshold (the minimal adversary ratio that can implement the attack with probability 1 despite the number of confirmation blocks) decreases when the synchronization time increases, and in the case of a large synchronization time, even an adversary with a minority hashrate can implement the attack with probability 1).…”

“…Note that all these works [ 3 , 4 , 6 , 7 , 8 , 9 ] investigate proof-of-work consensus protocol, but there are still no analogical results for proof-of-stake [ 10 , 11 , 12 ]. However, consensus protocol proof-of-stake is much more preferable than proof-of-work from a lot of points of view.…”