Quote from: BlackHatCoiner on March 17, 2024, 10:03:38 PM

Quote from: seoincorporation on March 17, 2024, 08:04:43 PM

Since the dominant pool (foundrydigital.com) only has 28.4% of the network, they can't do the 50% attack

Think of it this way: Anyone can attempt to execute a 51% attack. However, if you own less than half the hashrate, then it becomes exponentially less probable the more the blocks. However, you might stand lucky with 30% of the hashrate and reorg, say, the past 2 blocks. That is quite probable to happen in fact, you have 44.6% chance. What is exponentially improbable, as time goes by, is to maintain a chain with more work than the rest of the network, therefore to continue launching the attack forever.

By the time you will have started reorging the 5th to last block, the rest of the network will be way ahead of you, so you will have to work even more to keep up with the new blocks, and it goes on and on. The honest miners will build faster than the attacker, and outpace him.

You are totally right BlackHatCoiner but those are 2 different things, one thing is the 51% attack, where the miners can modify confirmed blocks, and the second thing is the double spend where the user modifies the unconfirmed transaction. In the past, when games used to be on-chain, people used to abuse double spends, recovering their money if the bet lost. And for that, they weren't even miners.

Quote from: BlackHatCoiner on March 17, 2024, 10:03:38 PM

That was the first quiz, and you all did pretty well. Class passed! More Bitcoin questions will come in the next days. Whoever has thought of a good question can drop me a PM, and I'll take it into consideration. Have a good week.

Thanks for the quiz, i really enjoy learning from the community and sharing knowledge, i will keep an open eye for the next quiz.