[ns] TCP retransmission mechanism

[Gustavo Da Costa <gmc50@student.canterbury.ac.nz>]

Hi,

I am running some wireless simulations where I have a mobile node
crossing cell boundaries after, say, 5s. If I set my wired link delay to
100ms, packets will be lost during this handoff. I also set window_ = 0
at 5s.

RFC 1122 says that if the window is reduced, TCP should not transmit new
data but it MAY retransmit lost packets. In my simulation I see that no
missing packets are retransmitted after window_ =0. Does anybody know if
this is what happens in real TCP implementations?

Thanks for your help,

Gustavo.