Since the chain trust is
only based on the length of the chain and not cumulated work, wouldn't it be quite easy to perform a double spend with much less than 51% hashrate?
On the original chain, send e.g. 10M XVG to an exchange.
While you wait for confirmations, start mining an alternative chain where you step down the difficulty by fakeing the timestamps. This should still be possible even though the maximum drift is changed to 10 minutes, it will just be somewhat slower. In this chain you include a transaction which invalidates your original transaction. Even if you only have e.g. 5% hashpower, your chain should eventually get longer than the original chain as it has much lower difficulty.
After you have converted the XVG to BTC on the exchange, you submit your privately mined chain to the network, and as it is longer than the original chain, it will cause the nodes to reorganize to your chain. Am I missing anything or would this be completly possible?
This would also make it possible to perform the attack with extremly limited ressources as you don't really have to compete with the honest miners.
that wouldn't work because the invalidation would also be accepted.
Could you expand on what you mean by the invalidation would also be accepted?
If you on your private chain sends the coins to yourself instead of the exchange, you will still own the coins when the network reorgs to your chain after you brodcasts your blocks.
bump for an unanswered serious question!
And bump for one more question:
- Why was the final block "halving" 730 instead of 780? Feeble attempt to hide the fact that more coins are being minted originally spec'd?
https://github.com/vergecurrency/VERGE#specificationsBlockreward:
Block 0 to 14,000 : 200,000 coins
14,000 to 28,000 : 100,000 coins
28,000 to 42,000: 50,000 coins
42,000 to 210,000: 25,000 coins
210,000 to 378,000: 12,500 coins
378,000 to 546,000: 6,250 coins
546,000 to 714,000: 3,125 coins
714,000 to 2,124,000: 1,560 coins
2,124,000 to 4,248,000: 730 coins
