This chapter provides additional technical detail about Microsoft 32-bit TCP/IP as implemented in Windows NT. This chapter is intended for network engineers and support professionals who are already familiar with TCP/IP or who have read the TCP/IP chapters in the Networking Supplement for Windows NT Server version 4.0.

Microsoft 32-bit TCP/IP for Windows NT is a high-performance, portable, 32-bit implementation of the industry-standard TCP/IP protocol. Microsoft has adopted TCP/IP as the strategic enterprise network transport for its platforms. The Transmission Control Protocol/Internet Protocol (TCP/IP) suite is a set of networking transports that govern how data passes between networked computers. Please evaluate any changes you make carefully.Chapter 6 - TCP/IP Implementation Details Chapter 6 - TCP/IP Implementation Details It is possible that hardware limits may be exceeded using these settings improperly, causing connectivity problems. NOTE: We have not fully evaluated possible repercussions of this OS change and recommend caution if it is used. Accomplished with following registry values follows by a system reboot:Ĭurrently monitoring 1586 devices with 1% cpu average core load, ~300kbps SNMP traffic on a gig wire Solution was setting the DefaultRecieveWindow & DefaultSendWindow to 64512. The default AFD parameters are badly optimized in Windows 2003 to serve modern applications, especially those using UDP. When (if?) buffer space clears up again, the operation eventually starts to complete again.Īnother user provided an update for this topic:Īfter reading about how the Windows TCP/IP is designed I realized that raising the AFD default buffer sizes might help solving the problem and it did! AFD is the kernel-mode driver that is used to support Windows Sockets applications and an underlying layer to Winsock.

This generally means that there is no buffer space available at the OS level to queue the send. Basically, this error from the UDP sendto operation means that the OS could not complete the sendto operation.

Any idea what the cause could be and if anything can be done to prevent it from happening?Ī. The problem persists for a couple of hours but then disappears. XSocketUDP_Win.cp: sendto errno 10035 (0) (0) Sometimes we lose a lot of UDP packages for some devices and see bunches of this message in the Debug log: We have an intermittent problem on one of our InterMapper servers.

Windows afd buffer default