Subject: Re: More TCP changes for review
To: Charles M. Hannum <email@example.com>
From: Greg Troxel <firstname.lastname@example.org>
Date: 01/27/2005 15:45:01
b) NS does not consider whether the send window is being updates
when it decides whether it has a duplicate ack. Why do we?
(Obviously if we didn't, we'd have to change the "goto drop"s to
avoid throwing out the window update.)
If there's a window update, the other side could have sent the ack
becaues of that, rather than because another segment from us arrived.
So it doesn't imply what a dupack implies for congestion control
I don't see any reason not to process urgent pointer updates on
dupacks. I wonder if a case can be made that an urgent pointer update
also disqualifies an ack from being used to clock out another packet.
But it would be odd for a peer to send data and then later decide to
move the urgent pointer.
Greg Troxel <email@example.com>