&gt; Not true - in firewall and security circles this was long ago observed and addressed in many different ways - it is now standard in at least the major Enterprise Firewall Vendors.<p>Hmm, what kind of measures are taken against this, then? Because aside from ingress filtering for RFC1918 addresses and the like, I don&#x27;t see how you could prevent this attack effectively. You could make it more difficult by rejecting wildly incorrect acknowledgement numbers, but I don&#x27;t see how to really prevent it.<p>&gt; Still though; the analysis is good, and clearly determined through work, observation, and sound logic. I would work alongside a person like this anytime.<p>Thank you! :)