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[ns] TCP Vegas implementation query - bug?



Hi all,

In the tc-vegas.cc file, during the congestion avoidance
mode, the code goes:

if (delta>v_beta_) {
	--cwnd;
	if(cwnd_<2) cwnd_=2;
	v_incr_=0;
} else if (delta<v_alpha_)
	v_incr=1/cwnd;
else
	v_incr_ =0;

I am a bit confused about the section where delta<v_alpha_.
According to [1] and [2], "when Diff<alpha, Vegas increases the congestion
window linearly during the next RTT." Then why is it that we are doing
v_incr_=1/cwnd? 

Shouldn't it be 
v_incr_=1;

[1]L.S. Brakmo, S.W. O'Malley, L.Peterson, "TCP Vegas: New Techniques for
Congestion Detection and Avoidance", 1994
[2]L.S. Brakmo, L. Peterson, "TCP Vegas: End to End Congestion Avoidance
on a global Internet", 1995

Regards,
Srijith
School of Computing
National Univeristy of Singapore