> > Are you sure !? TCP slows down by half on every dropped > > packet per congestion window AFAIK. > > On other side it is often hard to slow TCP down by packet > > delay as TCP will try to accomodate it by making MSS larger. > > Am I right jamal ? > > You basically need both, or your packet drops will constantly be fighting > retransmits as TCP is trying to recover. There will eventually be a balance, > but not a too nice one. I'd paste part of old jamal's email here: ---- Recall Mathis equation: TCP b/width = C*MSS/(RTT*sqrt(p)) where p is the drop probability and C is a constant which changes under different conditions ---- Additionaly TCP tries to adapt window to RTT so that min(MSS,cwnd)/RTT changes very slowly. Thus remaining part is C/sqrt(P). As you see - it is hard to slow TCP down without dropping... If you will set up infinite queue and delay by 1s the TCP will keep window increasing until drop occurs or reciever's advertised window is hit. I'd suggest you to read rfs2001. devik
