Did anybody ever hear about IP-addresses which get a slow treatment from some http servers ? We have a 195.212.127/24 out of a /16 PA range which is behaving very odd with multiple WEB servers but works fine with most others. When we configure an IP out of 195.212.127/24 on an direct Internet connected workstation, it takes about 1-2 minutes to start loading pages from some WEB servers, but it is fast for all other pages. When we then configure any other address out of this /24 onto the same client, everything works fine. We checked the WEB servers in question and they use various operating systems and Server software, so it does not seem to be a bug on the server side. A bug on the client side can be excluded as well because we tried various clients and it always works fine when an address outside the 195.212.127/24 is used. Routing also can't be the problem because after the "long" break traffic flows smooth. ************************************************************ 195.212.127/24 has for ex. problems with web-sites: http://www.infobel.com http://www.cevi.ch http://www.dropnet.ch No problems with web-sites: http://www.yahoo.com and http://www.google.com http://www.studerus.ch No problems to all of the above pages when using any other client IP address but the same Client Workstation and connectivity. ************************************************************ Sniffering on the client side shows, that the session establish goes through: 1. Client->Server HTTP: GET / HTTP/1.1$ 2. Server->Client TCP: TCP: src = 80, dst = 1944, ack = 0X3A577E76 ACK 3. Client->Server HTTP: HTTP/1.1 200 OK (http data is received now) Using a client address outside the range in question or going to a "good" HTTP-Server, goes through above three steps within some milliseconds. Using an address out of 195.212.127/24 and going to a "bad" HTTP-Server, works fine but then stucks for .5 to 2mins before going to above Step 3 and then all traffic flows smooth. To me it seems like the Servers are doing some intensive investigations on this IP addresses before getting the OK to process them. I have never heard of such a service. DNS/and reverse DNS can be ruled out as well as other, working addresses, are configured the same. Does anybody have any idea what the problem could be ? Thanks Dani