  Safety guarantees and security-latency problem of Nakamoto consensus have
been extensively studied in the last decade with a bounded delay model. Recent
studies have shown that PoW protocol is secure under random delay models as
well. In this paper, we analyze the security-latency problem, i.e., how secure
a block is, after it becomes k-deep in the blockchain, under general random
delay distributions. We provide tight and explicit bounds which only require
determining the distribution of the number of Poisson arrivals during the
random delay. We further consider potential effects of recent Bitcoin halving
on the security-latency problem by extending our results.
