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RE: [RPRWG] Frame reordering for medium priority traffic in Ganda lf?




Spencer,

We keep getting back to a single TCP connection.  This is not
one connection.  This is many connections bundled together.
We don't have control of which individual
connections get reordered.  For all we know, the connection 
with the least traffic will get affected.

In any case, this discussion is probably not appropriate for
for 802.17...debating ordered delivery may be more
appropriate for something like the end2end-interest list where
we have folks that are experts on this issue.  They understand
the issues and can explain the reason for recommending
in-sequence delivery much better than I can.
Their work tells us to minimize, if not eliminate, out-of-order delivery.  
It is better to drop packets than to routinely deliver them
out-of-order (as opposed to delivering out-of-order when some
failure or topology change occurs, which is a rare event).  
TCP flows are  by nature greedy so you will
routinely get to the point where you're out-of-profile.

-Anoop

> -----Original Message-----
> From: Dawkins, Spencer [mailto:Spencer.DAWKINS@xxxxxxxxxxxxxxx]
> Sent: Friday, December 07, 2001 8:14 AM
> To: stds-802-17@xxxxxxxx
> Subject: RE: [RPRWG] Frame reordering for medium priority 
> traffic in Ganda lf?
> 
> 
> 
> Sorry, but I'm still confused. How can reordering 
> out-of-profile TCP traffic make things worse? Either it 
> triggers fast retransmit/fast recovery, so the sending 
> station slows down its sending rate, or it doesn't trigger 
> fast retransmit/fast recovery, so there is no effect.
> 
> Spencer
> 
> -----Original Message-----
> From: Anoop Ghanwani [mailto:anoop@xxxxxxxxxxxxxx]
> Sent: Friday, December 07, 2001 10:05 AM
> To: 'Dawkins, Spencer'; stds-802-17@xxxxxxxx
> Subject: RE: [RPRWG] Frame reordering for medium priority 
> traffic in Ganda lf?
> 
> 
> 
> First, this is not a single station that we're talking about here.
> Second, the out-of-profile traffic was admitted because the
> network thought it could deliver it.  Reordering the traffic might
> actually make things worse.  It's like getting a freebie that might
> make your life worse without telling you about it.
> 
> -Anoop
>