[ns] Question about Tcp/Tahoe retransmission

[Baijian Yang]

Hi, all

I have a question about Tahoe retransmission.

I found that when congestion occurs ( I only tested 
Duplicate-action ), the Tahoe in NS simply retransmit 
everything from the lost packets, and leave the reciever
to judge whether it has seen the packets or not.

My question is: Is this also true in real case?
Seems it's not right. And another question is:
Does Reno or SACK in NS change the ways to react this siutation?

Thanks in advance!
Baijian Yang