"if you have the means to inject arbitrary packets, chances are you also have the means to read them" - this is not true in some (most?) settings. Current mode

"if you have the means to inject arbitrary packets, chances are you also have the means to read them" - this is not true in some (most?) settings. Current mode of operation of the Internet as we know it will allow incoming traffic allow to claim to stem from any public IP address. It's up to the interconnecting parties to ensure that no forged source IP adresses are used on packets leaving their network towards others, but that's all there is at the moment. See http://www.internetsociety.org/doc/addressing-challenge-ip-spoofing http://www.internetsociety.org/doc/addressing-challenge-ip-s...