Scott, Thank you very much for your help! I've posted my question to both tomcat-user and tomcat-dev newsgroup before I sent to you. Here I'll tell more about my program: System: Client ---- Firewall --- [ Web Server - cgi program - mux server ] --- Another Server the data flow for each HTTP POST request as follows (obtained from LanWatch32): The firewall(Raptor) HTTP proxy tends to send one POST request in two parts: HTTP header + HTTP content client(firewall) Web Server cgi program + mux server POST path to cgi program HTTP 1.1 .... other headers --------> Connection: Keep-Alive <----------- HTTP 1.1 100 continue ...... HTTP content ------------> it may take cgi program 1ms --- 100ms to process and send back HTTP reply <------------ HTTP 1.1 200 OK ...... other headers Connection: close HTTP content It happens both on Windows NT + IIS 4.0 and on Windows 2000 Server + IIS 5.0. My program works with Apache + Linux, the connection is never closed if set accordingly. My questions are: What's the parameters related to HTTP 1.1 connection? How to change them? Appreciate very much your kind help! Xuemei ----- Original Message ----- From: Scott Stahlman <[EMAIL PROTECTED]> To: xuemei <[EMAIL PROTECTED]> Sent: Saturday, May 19, 2001 1:01 PM Subject: RE: windows 2K + IIS 5.0 + cgi program + HTTP connection Keep Alive doesn't work Sorry for the late reply. Can you post this question on the newsgroup? It would be a great help, as you can probably imagine I must account for how I spend my time and posting this to the newsgroup allows us to do that. But see if http://support.microsoft.com/support/kb/articles/Q195/1/79.asp helps you at all. Thanks, Scott -----Original Message----- From: xuemei [mailto:[EMAIL PROTECTED]] Sent: Wednesday, May 16, 2001 4:20 AM To: Scott Stahlman Subject: windows 2K + IIS 5.0 + cgi program + HTTP connection Keep Alive doesn't work Hi, Scott I found your email address from the IIS Newsgroup. Sorry to bother you, but I really need some help soon. I just begin to use windows 2k Server and IIS 5.0 for my cgi program. The problem is that the HTTP connection Keep Alive is ON(by default), and the POST request to my cgi program also ask for Connection: Keep-Alive, but IIS always close the connection after sending reply to each request. There's no error at all, and even data is sent back though it's expired to Sender. How can I make HTTP 1.1 persistent connection work with IIS 5.0 on Windows 2000 Server? In fact, I have same problem with IIS 4.0 on NT 4.0 Server. Thank you very very much for your kind help! Xuemei