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Q125625: Software Compression Compatibility in Windows NT 3.5 RAS

Article: Q125625
Product(s): Windows for Workgroups and Windows NT Networking Issues
Version(s): winnt:3.5
Operating System(s): 
Keyword(s): kbbuglist
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 3.5 
- Microsoft Windows NT Server version 3.5 
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SUMMARY
=======

Several fixes were made to Windows NT Remote Access Service (RAS) that are
included in the latest U.S. Service Pack for Windows NT version 3.5. This
article provides background information on client compatibility with RAS.

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

NOTE: If you don't already have RAS installed, install it from your original
Windows NT installation media before applying the Service Pack.

RAS Software Compression Compatibility with Windows for Workgroups 3.11

and Windows NT 3.1
------------------

In addition to other fixes, the Service Pack installs files that make Windows NT
3.5 software compression compatible with Windows for Workgroups 3.11 and Windows
NT 3.1. Throughput should improve significantly unless previously compressed
files are copied. For best performance, Microsoft suggests you configure the RAS
client software on Windows for Workgroups 3.11, Windows NT 3.1, and Windows NT
3.51 (or Windows NT 3.5 with Service Pack 2 installed) as follows:

1. In Remote Access, make sure the Disable Software Compression option in the
  Options menu is not selected.

2. Choose the Edit button, then choose the Modem button, and select the
  following:

   - Enable Hardware Flow Control

   - Enable Modem Error Control

  Clear the Enable Modem Compression check box so software compression and modem
  compression are not used at the same time (as this reduces throughput).

Windows NT Servers and Clients and RAS Software Compression
-----------------------------------------------------------

If you install the Service Pack on a Windows NT 3.5 RAS server, unmodified
Windows NT 3.5 RAS clients do not lose software compression compatibility when
calling the RAS server. Windows for Workgroups 3.11 and Windows NT 3.1 RAS
clients can use RAS software compression without any need for new files, except
as noted below.

All copies of Windows NT 3.5 have RAS software compression built-in. Only Windows
NT 3.5 computers that are acting as RAS servers need the Service Pack for
compression compatibility with Windows NT 3.1 and Windows for Workgroups 3.11
RAS clients. However, because of several code improvements, Microsoft recommends
that you also apply this patch to Windows NT 3.5 RAS clients. The patch is
required for RAS software compression compatibility when you call a Windows NT
3.1 or Windows for Workgroups 3.11 RAS server from a Windows NT 3.5 RAS client.

Software Compression in Windows for Workgroups 3.11

and Windows NT 3.1 RAS Clients
------------------------------

Software compression is available, by default, in the following RAS clients
unless you select Disable Software Compression from the Options menu, or you
purchased your copy of Windows for Workgroups 3.11 or Windows NT 3.1 after
February 1994. You can tell whether or not you have RAS software compression by
using the following information:

Windows for Workgroups 3.11:

  Filename     Bytes   Compression
  --------------------------------
  RASMAC.386   49209   Yes
  RASMAC.386   27193   No

Windows NT 3.1:

  Filename       Bytes    Compression
  -----------------------------------
  ASYNCMAC.SYS   53188    Yes
  ASYNCMAC.SYS   53716    Yes
  ASYNCMAC.SYS   33732    No

NOTE: The Windows NT 3.1 and Windows for Workgroups 3.11 RAS compression files
can be obtained from the SUPPORT\RAS directory on the Windows NT 3.5 U.S.
Service Pack 2 compact disc.

STATUS
======

These fixes are included in the latest Windows NT 3.5 U.S. Service Pack. For
information on obtaining the Service Pack, query on the following word in the
Microsoft Knowledge Base (without the spaces):

  " S E R V P A C K " (without the quotation marks)

Additional query words: prodnt

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Keywords          :  kbbuglist
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTSsearch kbWinNTS350 kbWinNTS350search
Version           : winnt:3.5

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