How does a 51% crypto attack work?
Could you elaborate on the mechanics of a 51% crypto attack? I'm curious to understand how an attacker gains control of over half of the network's hashing power and how this allows them to manipulate the blockchain. Specifically, how does this impact transaction confirmation, double-spending, and the overall security of the cryptocurrency? Also, what are some of the strategies employed by attackers to acquire such a large portion of the hashing power, and how can networks defend against such attacks?