Wireshark-users: Re: [Wireshark-users] TCP Window Size and MTU/MSS
From: Hansang Bae <for_list_hbae@xxxxxxxxxx>
Date: Sat, 19 Feb 2011 15:01:48 -0500
On 2/10/2011 9:04 AM, Sake Blok wrote:
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)

But some systems will ack after two pkts of any size (which I think is more logical). Windows for example acks after two pkts regardless of size. This leads to less of a chance of a nagle/delayed-ack deadlock.

hsb