(Item 8322) Add DLUR segmentation support for short RSP(BIND) LUs               
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Several products have raised concerns with the current DLUR WBRI                
processing for SLUs sending short RSP(BIND)s.  The DLUR and NCP both            
assume that such a SLU cannot handle segments (indicating WBRI set on).         
However, when a PIU too large to be sent on the downstream link to the          
SLU is received, the DLUR will UNBIND the LU-LU session while the NCP           
will segment the message.                                                       
                                                                                
This is a mismatch of function putting the DLUR at a disadvantage (even         
though it is doing the right thing).  For easier migration, the DLUR            
should follow the NCP's procedure.                                              
                                                                                
The proposed solution is based on the realizations that:                        
                                                                                
   1) For APPN, WBRI has meaning for a hop, not the LU itself.  When            
      DLUR sets WBRI, it is indicating its own ability to handle                
      segments from the upstream hop, not the SLU's ability.                    
                                                                                
   2) When a SLU returns a short +RSP(BIND) for a BIND request whose            
      max RU size exceeded the downstream link capability, one can              
      infer an implied capability to accept segments at the SLU.                
      Detecting those conditions, a DLUR BF could send segments to              
      the SLU.                                                                  
                                                                                
   3) Some DLURs with memory constraints may be concerned that the              
      whole PIU sent from the PLU may exceed their capacity to                  
      receive it.  With segmentation on the downstream link now                 
      allowed, the DLUR could set WBRI off and accept segments from             
      the PLU but not reassemble them before sending anything to the            
      SLU.  The DLUR could pass the segments on to the SLU, or if the           
      PLU segment was too large for the link, break the PLU segment             
      up into multiple segments and send them to the SLU.                       
                                                                                
Therefore, it is proposed that the DLUR WBRI processing be updated with:        
                                                                                
   * if WBRI is reserved, act as if DLUR received WBRI=0; if segments           
     are received from the PLU, the DLUR can either:                            
                                                                                
       - reassemble the segments and attempt to send the whole                  
         message to the SLU (only if the DLUR supports segment                  
         reassembly); if the reassembled message is too                         
         large, the DLUR can segment the message and send the                   
         segments to the SLU                                                    
                                                                                
       - attempt to send the segments received from the PLU to                  
         the SLU; if a segment is too large, the DLUR can segment               
         the PLU segment and send the new segments to the SLU