5. The Man in the Middle attack.If an attacker succeeds to put himself between a merchant and the RaiBlocks network he can just filter the double spending payment packets, and the merchant will never know that he is receiving a double spending. The Raiblocks network will discard that payment while the merchant will accept it.
https://s18.postimg.org/7pnm6yweh/doublespend.png Couldn't the same MitM attack be used in a bitcoin transaction? Connect to all the peers of a merchant and mine 6 blocks containing the double spend while filtering out all longer blocks so the merchant accepts the transaction as valid.
No, because if you MITM a bitcoin merchant, you still have to mine 6 blocks with the difficulty bit set by the real network. And the difficulty only decrease by 1/4 every 2015 blocks. It will be impossible for an attacker to have such power.
Of course an attacker can mine 6 blocks. It will take more than an hour but it doesnt matter because all longer block chains are being filtered out. With 5% hashpower, an attacker could do it in a reasonable amount of time.
