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Q168599: SMS: Brief Overview of PGC for Windows 95 Clients in SMS 1.2

Article: Q168599
Product(s): Microsoft Systems Management Server
Version(s): winnt:1.2
Operating System(s): 
Keyword(s): kbnetwork kbsetup kbPGC smssetup smsappman smspgc kbSMSAppMan
Last Modified: 31-JUL-2001

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The information in this article applies to:

- Microsoft Systems Management Server version 1.2 
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SUMMARY
=======

This article provides a brief overview of 32-bit Program Group Control (PGC) for
Windows 95 clients in Systems Management Server 1.2.

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

In previous versions of Systems Management Server, PGC monitored and
reconfigured Windows registry settings each time an application was launched
using the Appstart functionality of PGC. This was done so that PGC would be able
to provide dynamic server selection at launch time. For this to work, a special
application (called Smssetup.exe) was required to perform these changes. This
implementation proved to be difficult to support, and a better solution now
exists for Windows 95.

Under Windows 95, Program Group Control performs server name substitution at the
file system level instead of reconfiguring the application at launch time. The
application gets installed normally, and then when it tries to use any of its
components, PGC recognizes that the application was installed from a Systems
Management Server package, connects to the Systems Management Server share point
at the file system level, and then the application can access the necessary
files. This functionality is only available to applications that are capable of
running from a UNC path (for example, \\servername\sharepoint).

The Systems Management Server Router technology (Program Group Control's file
system redirection capability) is implemented as a VxD file system driver called
Smsroutr.vxd. Applications that use the Systems Management Server Router
technology only deliver the application's setup icon to the user's desktop.
After the user installs the application from the icon delivered by Systems
Management Server, the application should be run from the icons created by the
setup program. Choosing the Systems Management Server-delivered icon will only
reinstall the application.

The implementation of Program Group Control for Windows NT clients has always
been 32-bit, but its functionality is identical to that of the 16-bit PGC that
runs on Windows 3.x clients. The new functionality of PGC under Windows 95 is
not available to Windows NT clients using Systems Management Server. Windows NT
clients run the shared application successfully, but only from the server that
the application was installed from. Therefore, load balancing and fault
tolerance will not be available for Windows NT clients.

NETWORK NAMING PROVIDER
-----------------------

Network Naming Provider (NNP) is a system application (running at Ring 3) that
provides the non-real time component of the Systems Management Server Router.
NNP loads at boot time, reads the system registry for Systems Management Server
information, formats that information, and passes it to the Logical Network
Redirector (LNR). In addition, NNP verifies server and share status as needed,
and updates the information for LNR.

LOGICAL NETWORK REDIRECTOR
--------------------------

Logical Network Redirector (LNR) is a Windows 95 system VxD (running at Ring 0)
that contains the real-time portion of Systems Management Server Router. LNR
loads at startup, hooks the installable file system (IFS) manager, and is
transparent to user applications. LNR is used to monitor appropriate file
operations for accesses to Systems Management Server controlled resources and
when necessary to redirect operations that fail to an alternate path. In
addition, LNR does load leveling on the initial use of a share.

Additional query words: prodsms win95 SMSRouter

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Keywords          : kbnetwork kbsetup kbPGC smssetup smsappman smspgc kbSMSAppMan 
Technology        : kbSMSSearch kbSMS120
Version           : winnt:1.2
Issue type        : kbinfo

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