iptables -t nat -A PREROUTING -s 192.168.1.108 -i wlan0 -p tcp --dport 554 -j DNAT --to-destination 10.7.36.221:554
iptables -t nat -A POSTROUTING -p tcp -d 10.7.36.221 --dport 554 -o eth0 -j MASQUERADE
原文：http://www.cnblogs.com/jingzhishen/p/5565028.html