3 ms·
The effect of this can be minimized by pre-comitting to which block will be used for entropy. Then antpool has a 10% chance of mining the relevant block, a (.1*
by tfha 7y ago
The effect of this can be minimized by pre-comitting to which block will be used for entropy. Then antpool has a 10% chance of mining the relevant block, a (.1*.5=0.05) 5% chance of mining an unwanted bit and discarding it, and then from there the chance that another unwanted bit is found will be close to 50%.
All considered that means antpool has a 2.5-3% chance of flipping an wanted result into a wanted result. At $125,000 per block, that's $4 million of cost per bit manipulated favorably, getting exponentially worse as you need to manipulate more bits.
- gus_massa 7y agoI think that the problem is that if you pick the first block mined after April 1st midnight, and there are two competing blocks, it will be a problem. In the blockchain one of the blocks will win sooner or later and it will be extended with a long enough chain to kill the other block. But the people that would have won the lottery with the other block will be angry. And remember that the timestamp of the block is oply an approximation. You can use any time you want. I'm not sure if the net reject the block when the time is too off, but you can use a fake delayed time of a few minutes and wait to broadcast it (perhaps mining secretly the next block), or perhaps you can use a fake previous time of a few minutes and blame the delay of the broadcast to a bad connection. (It's mode difficult to do this secretly in a pool.) The newspaper here make a big fuzz about the first baby of the year, and I always suspected the exact born time in that moment is not reliable.
- tfha 7y agoYou can solve this problem by picking a specific block height, and not confirming the result until it has at least 6 confirmations.