I have successfully performed a MITM attack and have managed to view the HTTP/HTTPS packets of the victim passing through the nat table of the PREROUTING chain of my iptables.(using -j LOG) However, why am I not able to see Skype traffic from the victim in the nat table of the PREROUTING chain as well? The Skype traffic appears normally in the raw and mangle table but somehow 'disappears' from the nat table. I have already enabled ip forwarding. Any possibilities for this weird behavior? The Skype traffic is simply just TCP encrypted with TLS.