Explanation of Gateway Services for NetWare

ID: Q121394


The information in this article applies to:


SUMMARY

The objective of Gateway Services for NetWare (GSNW) is to allow Microsoft networking clients to access files that reside on NetWare servers without having to load NetWare client software. Following is a brief description of how GSNW works.


MORE INFORMATION

GSNW Details

A Server Message Block (SMB) request can come from a variety of Microsoft Networking clients over a variety of network transport protocols. For example, the Microsoft client could be a Windows NT client using Remote Access Service (RAS) to dial into the network or a Windows for Workgroups client attached directly on the network, either using IPX/SPX, TCP/IP, or NetBEUI.

When an SMB request reaches the Windows NTAS file gateway machine, it is initially picked up by the Windows NT Server Service (SRV.SYS) [1].


         --------------------------------------------
         |      Windows NTAS GSNW Gateway           |
         --------------------------------------------
                            |
                            |
--------------------------------------------------------------------

      ---------------------------
[1]   |  SMB file I/O request:  |        -----------------------
      |  open ,create, delete   |----->  | outgoing NCP packet | ---->
      |                         |        -----------------------
      |    Properties:          |
      | share name= \\KOACH     |
      | file path= \SYS\DATA    |
      | file name = MYDATA.DAT  |
      ---------------------------
      |                         |
      |       Transport         |
      |                         |
      --------------------------- 


The MS Networking client sends out the SMB request. If the request is a file manipulation request (a request that requires a file handle to be returned), SRV.SYS uses the above share name, file path, and file name to open the file object [2].




            |------------------------------------------|
            |      Windows NTAS GSNW Gateway           |
            --------------------------------------------
                               |
                               |
     ---------------------------------------------------------
     |        [2]                                 [3]        |
     |   -----------------             -------------------   |
     |   |    SRV.SYS    |             |    NWRDR.SYS    |   |
     |   -----------------             -------------------   |
     ---------------------------------------------------------
                               |
                               |
---------------------------------------------------------------------
incoming SMB packet ----->        outgoing NCP packet -----------> 


In the example above, the object name is \device\nwrdr\koach\sys\data\mydata.dat. SRV.SYS calls the Windows NT API NTCreateFile, passing the object name. The Windows NT I/O manager uses the file object name to call into NWRDR.SYS [3], passing NWRDR.SYS information on the security token of the object that sent the SMB. Based on the security token, NWRDR.SYS determines if the request was from a local account or a remote request. If the request was a remote request, NWRDR.SYS uses the gateway credentials when sending the file manipulation NCP to the NetWare file server [4].


            |------------------------------------------|
            |      Windows NTAS GSNW Gateway           |
            --------------------------------------------
                               |
                               |
----------------------------------------------------------------------

-----------------------               ----------------------------
| Incoming SMB Packet | ---->         |  NCP file I/O request:   |
|                     |               |  open, create, delete    |[4]
-----------------------               |                          |
<BLOCKQUOTE>
                                      |    Properties:           | -->
                                      |  share name= \\KOACH     |
                                      |  file path = \SYS\DAT    |
                                      |  file name = \MYDATA.DAT |
                                      |                          |
                                      ----------------------------
                                      |           IPX            |
                                      ---------------------------- 


NWRDR.SYS returns the file handle to the Windows NT I/O manager, which then returns the file handle to SRV.SYS. Further SMB traffic related to this file manipulation request (for example, if the file manipulation request was to open a file for reading) will be sent directly to NWRDR.SYS by SRV.SYS using the file handle.

NetWare is manufactured by Novell, Inc., a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.

Additional query words: wfw wfwg prodnt 3.1 3.5 hook gsnw


Keywords          : NTInterop ntnetserv ntprotocol 
Version           : winnt:3.5,3.51,4.0
Platform          : winnt 
Issue type        : 

Last Reviewed: July 27, 1999