[Csci551-talk] Doubt regarding TCP congestion control.

[affan syed]

There is no discrepency. Note that the jacobson paper is talking about increasing by 1/cwnd for every *ack*, so if everything is hunk dory, you will get cwnd Acks in one RTT and at the end of the RTT you will have increased you cwnd by..... cwnd *1/cwnd =1.

hth.
Affan
----- Original Message -----
From: rashmi chandrasekhar <rmchandr at usc.edu>
Date: Thursday, March 10, 2005 9:54 am
Subject: [Csci551-talk] Doubt regarding TCP congestion control.

> 
> The Jacobson paper talks about congestion avoidance and states 
> that, on congestion, we reduce the cwnd to 1 and increase by 1/cwnd 
> (additive increase) on receiving each ACK. 
> 
> However, the TCP lecture slide 5c_tcp_class.pdf, slide #67 says 
> what TCP does is "sort of a multiplicative increase" : 1 pkt each 
> RTT if doing congestion avoidance (when cwnd > ssthresh) 
> 
> I am confused with this discrepancy. Is it because the Jacobson 
> paper says what happens in practice and the slide says what should 
> happen in theory ? 
> 
> Thanks.
> 
> -Rashmi.
> 
> 
>