
              NOVELL TECHNICAL INFORMATION DOCUMENT

TITLE:              Packet Burst Files for WAN Links
DOCUMENT ID:        TID014298
DOCUMENT REVISION:  B
DATE:               21JAN94
ALERT STATUS:       Yellow
INFORMATION TYPE:   Symptom Solution
README FOR:         PBURST.EXE

NOVELL PRODUCT and VERSION:
NetWare 3.11
NetWare 3.12
NetWare 4.01

ABSTRACT:

This file contains Packet Burst files that implement a new packet burst
algorithm for WAN links.  PBURST.NLM is for use on NetWare v3.11 file servers
and PBWANFIX.NLM with patchman are for either the v3.12 or v4.01 NetWare
O/S's.  The packet burst files contained in this file need to be used with the
v1.10 VLMs contained in DOSUPx.EXE to allow the new packet burst algorithm to
function.  Fixes saturation of WAN links with resent packets from a previous
burst, that were already received at the other side of the WAN link.


DISCLAIMER
THE ORIGIN OF THIS INFORMATION MAY BE INTERNAL OR EXTERNAL TO NOVELL.  NOVELL
MAKES EVERY EFFORT WITHIN ITS MEANS TO VERIFY THIS INFORMATION.  HOWEVER, THE
INFORMATION PROVIDED IN THIS DOCUMENT IS FOR YOUR INFORMATION ONLY.  NOVELL
MAKES NO EXPLICIT OR IMPLIED CLAIMS TO THE VALIDITY OF THIS INFORMATION.


SYMPTOM

     Saturation of WAN links with resent packets from a previous burst, that
     were already received at the other side of the WAN link.  Disabling
     packet burst increases the throughput over WAN links.

SOLUTION

     Apply PBURST.EXE

     Self-Extracting File Name:  PBURST.EXE     Revision:  B

     Files Included     Size     Date      Time

     \
       PBURST.TXT         (This File)      
       PBURST.NLM      95752   11-04-93    4:32p
      APPNOTE.TXT      32917   11-16-93    2:19p
     \PBWANFIX.312\
        PM312.DOC       3693   11-11-93    4:33p
        PM312.NLM       8909   11-11-93   11:52a
     PBWANFIX.NLM       1344   10-18-93   11:40a
     \PBWANFIX.401\
        PM401.DOC       3682   11-08-93    2:47p
        PM401.NLM       8113   08-26-93   10:38a
     PBWANFIX.NLM       1291   10-18-93   11:39a


     Installation Instructions:

     Extracting this file will cause a PBWANFIX.312 and a PBWANFIX.401
     directory and associated files to be created.

     For a file server v3.11 Operating system:

     1)   Copy PBURST.NLM to the SYS:SYSTEM directory, or the local drive on
          the file server.
     2)   At the console, type LOAD PBURST
     3)   Add LOAD PBURST.NLM to the file server's autoexec.ncf, to ensure
          that Packet Burst is loaded each time the server is re-booted.

     For a file server v3.12 Operating system:

     1)   Copy PM312.NLM and PBWANFIX.NLM from the PBWANFIX.312 directory in
          this zip file, to the SYS:SYSTEM directory, or the local drive on
          the file server.
     2)   At the console, first type LOAD PM312
     3)   At the console, then type LOAD PBWANFIX
     4)   Add LOAD PM312 and LOAD PBWANFIX to the file server's autoexec.ncf,
          to ensure that Packet Burst is loaded each time the server is
          re-booted.

     NOTE:     This version of patchman for 3.12 cannot be loaded from the
               server's startup.ncf file.

     For a file server v4.01 Operating system:

     1)   Copy PM401.NLM and PBWANFIX.NLM from the PBWANFIX.401 directory in
          this zip file, to the SYS:SYSTEM directory, or the local drive on
          the file server.
     2)   At the console, first type LOAD PM401
     3)   At the console, then type LOAD PBWANFIX
     4)   Add LOAD PM401 and LOAD PBWANFIX to the file server's autoexec.ncf,
          to ensure that Packet Burst is loaded each time the server is
          re-booted.

     GENERAL INSTALL INFORMATION FOR PATCHMAN/PATCHES:

     Dynamic patches are loaded at the file server console as NetWare Loadable
     Modules and require PM401.NLM or PM312.NLM to be loaded.

     It is recommended that the command "LOAD <patch name>" be placed in the
     server's AUTOEXEC.NCF file to ensure that the patch is always in effect
     when the server is initially brought up.

     Since they are NLM's, the patches can be loaded and unloaded without ever
     having to bring the server down. Once loaded, the Operating System is
     patched and ready to go.

     Unloading the patches will restore the Operating System to its original
     "un-patched" state.

          Installation:

     To install a specific patch or patches, simply place the patch file in
     the same directory as the other NLM files (SYS:SYSTEM or DOS partition),
     and type "LOAD <patch name>" for each patch you wish to load.  Once a
     patch has loaded, all changes are in effect until it is unloaded.  If an
     error message appears, contact Novell Technical Support.  As suggested
     above, you will probably want to enter the LOAD commands into your
     AUTOEXEC.NCF file to insure that the patches are loaded automatically.  

     MODIFICATIONS INCLUDED WITH THESE FILES:

     Short write timeouts don't work well over WAN links, because the server
     doesn't have a good idea of the transport time.  We now will prevent the
     server from asking for data that is currently in transit from the client.
     Also changed packet burst so that when it gets a duplicate read request,
     it will only reply with a short piece of the data, rather than replaying
     the whole burst - thus causing the client to ask for individual pieces
     with system packets (for the case where the initial packet was really
     dropped.)  The benefit is when "read data" over a WAN link is already in
     route to the client, but the client hasn't seen it yet, we; 1) still get
     the data we have already sent, 2) we will not flood the line with
     unnecessary duplicate packets.

     Moving timeout algorithm has been removed.  Timeouts now are based off
     the initial round trip time calculated as connect time.  If the LIP echo
     socket is not supported on a server (i.e. 2.x NetWare, or 3.11 without
     PBURST loaded), a default of (MLID transport time * 4 + 10) ticks is
     used.  Workstations connected to WANs may override this with a NET.CFG
     command "MINIMUM TIME TO NET"

     This is needed for bridged WAN/Satellite configurations where the
     time-to-net we get from the router is much too low.  This NET.CFG
     parameter must be used in these configurations when the server on the
     other side of the link is NetWare v2.x, or NetWare 3.11 (without
     PBURST.NLM loaded) since these servers don't support the echo socket
     which we use to measure the actual time to net.  This parameter may also
     be needed when using a link of 2400 baud or less.  The parameter value is
     in milliseconds (a value of 1000 = 1 sec).


     ASSOCIATED NET.CFG PARAMETERS FOR THIS VERSION OF VLMs:

          PB BUFFERS = n   (0-10)    default=3  

     Note:     0 is disabled, non-zero is enabled.  See APPNOTE.TXT pages 6
               and 7 for an explanation of the changes to this parameter, and
               influence this parameter has on performance/memory.

          PBURST READ WINDOW SIZE = n   (3-255)    default=16

     Note:     See "Window Size in the VLMs" pages 8-10 in APPNOTE.TXT for an
               explanation of this parameter.

          PBURST WRITE WINDOW SIZE = n   (3-255)    default=10

     Note:     See "Window Size in the VLMs" pages 8-10 in APPNOTE.TXT for an
               explanation of this parameter.

          MINIMUM TIME TO NET = n   (0-65535)

     Overrides the "time-to-net" value defined by the local router during
     connection time.  This parameter is used for bridged WAN/Satellite links
     with "time-to-net" values set to low for workstations under the following
     conditions to make a connection:

     1.   The server on the other side of the link is a non-pburst 3.x or
          below server.

     2.   The transfer rate for the link is 2400 baud or less.

     Note:     The value is set in milliseconds.  i.e. MINIMUM TIME TO NET =
               10000  would set the value to 10 seconds.

     If the w/s cannot make an initial connection, try increasing this
     parameter.  In a packet bursting environment, the value will adjust back
     down after the initial connection, to a more optimal value.  HOWEVER, if
     the workstation connects to a non-bursting server, this value stays at
     the value set in the net.cfg.  If this value is artificially high, it may
     adversely affect performance.


          GENERAL

     The December 1993 "NetWare Application Notes" has an article covering
     VSAT (Very Small Aperture Terminal) and


     Solution Specifics:

          PBURST.NLM     95,736 10-07-93 11:40 v2.02 NCP Packet Burst Support,
                         Large Internet Packets And Packet Signatures.

          PBWANFIX.NLM   1,344 10-18-93 11:40 v1.00 312 patch to fix Packet
                         Burst packet storms on WANs (931018)

          PM312.NLM      9,586  8-31-93  2:35 v1.10 Patch Manager for NetWare
                         v3.12 (930831)

          PBWANFIX.NLM   1,291 10-18-93 11:39 v1.00 401 patch to fix Packet
                         Burst packet storms on WANs (931018)

          PM401.NLM      8,113  8-26-93 10:38 v1.11 Patch Manager for NetWare
                         v4.01 (930826)

          PBURST.TXT     (This File)

          APPNOTE.TXT    is a reprint of the November 1993 appnote comparing
                         packet burst under the BNETX vs. VLM environments. 
                         Satellite delay influences on packet burst.

