not sure ESTABLISHED TCP traffic will have ACK flag setalways...

seberino at seberino at
Sun Apr 10 05:23:08 CEST 2005

> When the faster sending site sends it's packets to the slower
> site the packets that are sent (1234, 1235, 1236, 1237...) will all
> the same Acknowledgment number set in their packet stating that the
> packet the faster sender receives from the slower client should be
> Sequence number.


Wow!  Thanks again.  You cleared up the last missing piece about ACKs!
So the slow side can ACK multiple sequence numbers with a single
packet.  Likewise, the /fast/ side can send multiple ACKs for
the same repetitive sequence number.  That makes perfect sense.

Now I believe that TCP packets can all have ACKs set on an
ESTABLISHED connection.


P.S. BTW, I'm curious how you knew this level of great info.  Did you
carefully read through RFC 793?  That was jam packed with info but
hard to digest fully.

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