On 10 feb 2011, at 14:20, neerav panwar wrote:
> I have seen whatever be the receive window size, TCP sens ack after 2 or 3 packets of any length. It doesn't receive data as per window size.
> Exa: If receive window size is 64000 bytes and MSS/MTU is 1460 then ACK should come after 64000/1460 packets. But receiver always sends ack
> after 2 or 3 packets maximum.
> The changes done on tcpackfrequency doesn't pay off on a windows XP.
> What is the way decrease the number of ACKs over the link?
See RFC 2581 part 4.2 :
The delayed ACK algorithm specified in [Bra89] SHOULD be used by a
TCP receiver. When used, a TCP receiver MUST NOT excessively delay
acknowledgments. Specifically, an ACK SHOULD be generated for at
least every second full-sized segment, and MUST be generated within
500 ms of the arrival of the first unacknowledged packet.
(http://www.faqs.org/rfcs/rfc2581.html)
Cheers,
Sake