On Thu, Jul 26, 2001 at 04:04:21PM +0200, Rami Cohen wrote:
> Hi Andi,
> Thanks for your comments and your help.
> I'm aware to RFC 793 statement regarding to ACK.
> My problem is that these piggyback ACK can cause duplicate ACK and therefor
> invoke the
> Fast Retransmit mechanism.
> Consider the following situation when the sender send TCP segment and the
> receiver send
> Then the sender send another 3 (or more) segments, and meanwhile it receives 3
> piggyback ACKs that have been sent by the receiver (i.e. the receive send 3
> TCP frame
> before it receives the 3 packets that has been sent by the Sender).
> The sender can assume that these ACKs are duplicate ACK and therefor it
> enters into
> Fast Retransmit although it shouldn't.
> Can you help me with this issue.
The dupack counter only counts acks which do not carry any data ("pure acks")