[hinkley]

Not every distributed consensus algorithm is happy with 51%. If you increased the minimum to 60% you’d increase the number of machines the attacker requires by 50%.

If 100 machines play fair, >50% requires 101 evil machines, but >60% requires 151 evil machines.

[Rodyland]

I think you're misunderstanding the meaning behind a 51% attack?

An honest network participant will accept the chain with the largest accumulated proof of work. This is necessary to resolve forks of the chain, which are a natural occurrence.

A 51% attack means that the attacker can create a chain with more work than the rest of the network.

The idea that you can say "we require 60%" makes no sense by itself - you have to say what you actually mean in the context of a competitive and adversarial distributed proof of work blockchain network...

Maybe you have some ideas how to avoid history-rewriting attacks, in which case you should write a white-paper and launch your own sh1tcoin or ICO (only half joking).

[hinkley]

Thank you for helping me put into words what bothers me about crypto currency. We’ve deployed an AP algorithm for financial transactions. That’s not fixable.

[Jommi]

You're only describing how it works with Bitcoin and other coins that are forked (git-forked) from it.

Some blockchains require a higher amount of consensus to fork (blockchain fork).

[XR0CSWV3h3kZWg]

Could you point to a PoW based cryptocurrency that isn't vulnerable to a 51% attack?

[Jommi]

you're right, I was mixing up some concepts in my mind, sorry!

For others who might be confused, here is a good resource:

https://bitcoin.stackexchange.com/questions/26999/supermajor...