Hi, i observed windows 7 TCP stack (in my PC) always sends TCP ACK message to server(sender) after receiving two segments(1460 byte X 2) even though receiver window size 17520 byte. i feel if we can wait more segments to receive and send ACK can improve data speed. can anyone help me to understand how windows 7 TCP stack behaves. regards DT

Hi DT, Thank you for the post. As the symptom is on Windows 7 computer, I suggest you post it to Windows 7 forum for the explanation. http://social.technet.microsoft.com/Forums/en/category/w7itpro Thank you for your understanding. RegardsRick Tan TechNet Community Support