What is that of blacklisting?
I don't understand it really well
It's basically DDOS protection.
Yes, except who has the power to alter who is classified as an "attacker"? Once you can blacklist an IP can't someone decide to apply to it anyone?
Its a rule not a protocol. Anyone run wallet client can use any rules they want regarding relay txs.
Frankly the code in bitcoinXT clearly shows how it determines attackers.
That does not mean someone cant change the code for their own clients to fit their definition of attackers.
Are you aware that this has been with bitcoin core wallet client as well? Many users actually add their rules to block dice websites.
Now dont fall for FUD like this next time. Take step to validate what you're told