Eric Smith wrote: > Kristján Valur Jónsson wrote: >> Aha, thanks, since my wireshark wasn't working. >> I boiled a few pints of water (thanks, Google) and came up with this: >> >> http://support.microsoft.com/kb/175523 >> >> Here is the summary: >> Note that with other implementations of TCP, such as those commonly >> found in many UNIX systems, the connect() fails immediately upon the >> receipt of the first ACK/RST packet, resulting in the awareness of an >> error very quickly. However, this behavior is not specified in the >> RFCs and is left to each implementation to decide. The approach of >> Microsoft platforms is that the system administrator has the freedom >> to adjust TCP performance-related settings to their own tastes, namely >> the maximum retry that defaults to 3. The advantage of this is that >> the service you're trying to reach may have temporarily shut down and >> might resurface in between SYN attempts. In this case, it's convenient >> that the connect() waited long enough to obtain a connection since the >> service really was there. >> >> Yet another "undefined" thing affecting us, Martin. > > I know it's pointless to express my shock here, but I can't resist. It's > truly amazing to me that they'd delay the connect call's failure for a > second by default, in hopes that the other end might come back up > between SYN's. How often could that possibly happen? > When I read it I was tempted to observe they must have been testing Microsoft network services. It is a truly bizarre rationalization of a default that appears to have been taken from DOS-era network client applications. I remember demonstrating the phenomenon on a cli-based Telnet client at least 15 years ago.
regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com