Clearly, when I use iptables to drop packets in output of a sender A, the TCP instance of A re-send them because it never gets ACK from the receiver B of those lost packets. In the end, depending on the probability of drop (>0), all data from A might get to the receiver B. Packet loss thus induces network delays and the increase of TCP segments being send on the network. Will I face the same situation using ipfw ? Are the packets handled before or after the TCP state machine ? All information I could get, even of the dummynet official page, is not clear about it, even the googletechtalk.
I thank you in advance for any help.