



                        Citrix Winview
                        Technical Note

                        Novell, Inc.
                        NetWare NetWare V3.11 
                        Packet Burst NCP Protocol 
                        
                        This technical note is for
                        informational use only and Citrix
                        makes no representations or
                        warranties with respect to the
                        contents or use of this document or
                        of any of third-party products
                        discussed within.


(December 6, 1994)

Citrix Systems
210 University Drive
Suite 700
Coral Springs, FL 33071
Phone (305) 755-0559
FAX   (305) 341-6880


Overview:
---------


        This technical note facilitates the configuration and installation
of 'Burst-Mode' NCP protocol for use between Novell NetWare V3.11 Network 
servers and "WinView for Networks" Application Server Software.

 NOTE: Novell NetWare 3.12 and 4.x integrate Packet Burst Mode Protocol 
       functionality within the Network Operating System (NOS). No modules need 
       to be loaded to enable bursting. Under WinView for Networks, only Vshell 
       (Global Logins) is supported in DOS sessions. Netx will not use the 
       features of Packet Burst.

        
        
        
        The Burst Mode is a special-purpose service protocol provided for NCP
(Netware Core Protocol) read and write requests. It is built on top of IPX; as 
such, it is similar to SPX in that it is a connection-oriented protocol. As a
special-purpose service, it has been optimized to avoid the overhead of acknow-
ledging the delivery of each packet, as does the SPX protocol.

        Although IPX does not require one-request, one-response type communic-
ation, the normal NCP implementation usually does. Burst mode, however, commun-
icates using multi-packet units. A multi-packet unit, including:

        * The IPX headers for each packet
        * the burst headers for each packet
        * and the request or reply, with or without data

is called a Burst. The packets that make up the burst are called fragments. 
Theoretically, on burst may be up to 64K in length.


Disclaimer:
-----------

        The scenarios described in this document have been tested by Citrix
Systems.  Other variations to the scenarios described in this document may work,
however they have not specifically been tested by Citrix.  In order to recreate
the configurations, you should use the specified revision levels of all software
products described in this document and stay within the bounds of the features
and functions described in this document.

        Please note that this technical note is a living document and will be
modified as new information and versions of the software described herein
become availiable.  Make sure you have the latest version of this document
before you begin.  The latest version is always available in the Citrix Forum
on Compuserve.

Requirements:
-------------

        1. Citrix WinView for Networks Version 2.21 or higher

        2. Novell V3.11 FileServer

        3. PBURST.EXE archive from NetWire on CompuServe, or NSEPRO

        4. BURST1.TXT document from NetWire on CompuServe, or NSEPRO


Theory of Operation
-------------------

        A burst transaction occurs from the beginning of the burst request to 
the end of the reply. For example, when a client sends a request to read a file
the burst transaction begins. The fileserver sends a series of packets (burst)
to the workstation, indicating the last packet with an End of Burst flag. When
the client receives that packet, the burst transaction is complete, if there are
no missing fragments. If fragments are missing, the client sends a missing 
fragment list to the server, which then retransmits the missing fragments. This
process continues until all missing fragments are received by the client, or
until a timeout is reached.


Installation
------------

        Implementation and usage of Packet Burst Mode is very straightforward.
This section will cover the steps needed to correctly install and use Burst
Mode. Any files mentioned can be found in the Novell Libraries on CompuServe.
While on CompuServe, type 'GO NETWIRE' to reach the Novell area, and go to the
downloads area.


A. On your NetWare V3.11 Server (3.12 and 4.x have Packet Burst already enabled
   so no modules need to be loaded.), extract the PBURST.EXE archive, and
   place PBURST.NLM in SYS:SYSTEM directory, and type LOAD PBURST  to load
   the NLM.
B. To avoid security problems, on the V.311 server console, type the following
   lines:

   SET ALLOW UNENCRYPTED PASSWORDS=ON
   SET NCP PACKET SIGNATURE OPTION=1

To monitor the Packet Burst client connections, type:
   SET ENABLE PACKET BURST STATISTICS SCREEN=ON

C. the Above lines should also be placed into the AUTOEXEC.NCF file on the
   server, so that Packet Burst will always be active, even after server
   reboots.

For further reference on Packet Burst Protocol, refer to Novell's NSE PRO
support encyclopedia on CD-ROM, keywords 'packet|burst'. The bulk of this 
document was taken from BURST1.TXT from the 94-7 edition of NSEPRO. All
original copyrights and trademarks remain in effect. 


Notes
-----

Novell NetWare 3.12 and 4.x integrate Packet Burst Mode Protocol functionality
within the Network Operating System (NOS). No modules need to be loaded to
enable bursting.

Under WinView for Networks Application Server software, only Vshell (Global 
Logins) is supported in the DOS sessions. Netx (Private Logins) will not
use the features of Packet Burst


Problems
--------

There are no known problems at this time.
