Quote from: cr1776 on December 24, 2013, 08:34:59 PM

If the two pools collude for a 51% attack, what would they gain? A double spend? What would the double spend get them?

There's more to gain than just double spending. Double spending is something the pool can do if it chooses. If they created a fork in the blockchain, they could double spend some coins and get away with it, which is what I think another post was referring to, coins getting lost forever. But say for example we're the powerhouse pool and we wanted to be bad... {Girl power!} Crap, am I by myself here? Damn it.

Anyhoo, we created our version of the blockchain and it has all real transactions up until yesterday's. Today's transactions are bogus btw... we sent some coins there, and over there. Since we're the authoritative bitch (majority of computing power) theoretically we could force other pools to point to our 'fake' blockchain and accept our made up transactions from today. But I suspect we'd eventually get caught doing it this way. We should probably just pluck random, semi-large transactions.

I think we're getting too caught up with the term attack. We want to think of a 51% attack as being intentionally malicious... Agreed, a pool out for gain intentionally exploiting their power/network can do some damage. But what about the unintentional consequence of having over 51% of the hashing power? Are we just going to dismiss this and focus on the bad stuff they can accomplish?

Quote from: Lucky Cris on December 24, 2013, 06:57:05 PM

A 51% Attack doesn't have to be intentional, does it? If any pool had 60% of the hashing power, an attack would be forthcoming. The pool doesn't have to try to do it, it will, which is why the pools cap themselves. Blocks other miners solve would be orphaned left and right... The longest chain always win the conflict, right? That isn't to say it was done intentionally or with malice. But whoever has the upper hand would benefit from the block rewards and transactions fees of those resolved 'conflicts.' On the other hand, if a pool wanted to orchestrate an attack... well, I guess that's another topic.

Quote from: Lucky Cris on December 24, 2013, 07:33:16 PM

Can you explain how it works, or how the pool can prevent from abusing that power? Can that power be abused - oh, hell yes! I'm not talking about the many things that a pool powerhouse has the ability to do.... But how can said pool prevent from NOT taking other miners' block rewards and transaction fees? This isn't intentional - As the authority on the network (so to speak), clients will believe the pool's hashed transaction block over any other. That means the pool will win all transaction conflicts, and get the rewards.

Anybody? Or am I over-analyzing. For the purpose of your response, let's say it's an "honest pool."