DOCUMENT:Q117715  13-JUN-2001  [win3x]
TITLE   :Slow Performance over IBM Software Source Routing Bridge
PRODUCT :Microsoft Windows 3.x Retail Product
PROD/VER::3.11
OPER/SYS:
KEYWORDS:kbfile kbgraphxlinkcritical

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3.11

WINDOWS

kbnetwork kbprb kbfile

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The information in this article applies to:

 - Microsoft Windows for Workgroups version 3.11 
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SYMPTOMS
========

Data transfers across a source routing bridge are very slow or appear to hang.

CAUSE
=====

Windows for Workgroups (NetBEUI protocol) over a Token Ring Source Routing
Bridge advertises a Largest Frame (LF) size of 8130 bytes. However, the Maxframe
size is negotiated at 156 bytes. This causes very slow data transfer.

A network trace illustrates the problem:

   Destination   Source        Summary
   Server      WFWClient<00>   NETB D=2B S=16 Session initialize

   NETB: ----- NETBIOS Session Initialize -----
   NETB:
   NETB: Header length = 14, Data length = 0
   NETB: Delimiter = EFFF (NETBIOS)
   NETB: Command = 19
   NETB: Flags = 89
   NETB: 1... .... = NO.ACK ability

   NETB: .... 100. = Largest frame value = 4 <<<8130 bytes -IBM Spec

   NETB: .... ...1 = Version 2.0 or higher

   NETB: Max data receive size = 156     <<< Small Frame size negotiated.

   NETB: Transmit correlator = 0000
   NETB: Response correlator = 0016
   NETB: Remote session number = 43
   NETB: Local session number = 22

If the bridge advertises a size OTHER THAN 8130 bytes, this problem does not
occur.

WORKAROUND
==========

An updated NETBEUI.386 file is available to correct this problem. Replace your
existing NETBEUI.386 file with the updated version. For information about how to
obtain the updated driver, refer to the More Information section below.

The following options allow you to work around this problem:

 - Use the real-mode NetBEUI protocol.

   -or-

 - Execute "Net start Full" at the command prompt before running Windows for
   Workgroups.

   -or-

 - Configure the bridge by changing a Largest Frame size (smaller or larger).

   In a case where an IBM software bridge is used to connect two 16 MB rings, it
   is not possible to change the LF size on the bridge software. In this case,
   you can bring down the network ring to 4 MB, or install a hardware bridge.

NOTE: This problem does not occur on LAN Manager/Windows workstations.

MORE INFORMATION
================

The following file is available for download from the Microsoft Download
Center:

   DownloadDownload Netbeui.exe now
   (http://download.microsoft.com/download/wfw311/Update/1/WFW/EN-US//Netbeui.exe)

For additional information about how to download Microsoft Support files, click
the article number below to view the article in the Microsoft Knowledge Base:

   Q119591 How to Obtain Microsoft Support Files from Online Services

Microsoft used the most current virus detection software available on the date of
posting to scan this file for viruses. Once posted, the file is housed on secure
servers that prevent any unauthorized changes to the file.

STATUS
======

Some of the products discussed here are manufactured by vendors independent of
Microsoft; we make no warranty, implied or otherwise, regarding these products'
performance or reliability.

Additional query words: 3.11 TR bridging client hangs freezes locks

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Keywords          : kbfile kbgraphxlinkcritical 
Technology        : kbAudDeveloper kbWFWSearch kbWFW311
Version           : :3.11

=============================================================================

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