RE: iSCSI: keys/parameter dependence

["Julian Satran" <Julian_Satran@il.ibm.com>]

The text should read now:

       If DataSequenceInOrder is set to Yes, a target may retry at most the
       last R2T, and an initiator may at most request retransmission for
       the last read data sequence.  For this reason if ErrorRecoveryLevel
       is not 0 and DataSequenceInOrder is set to Yes then MaxOustandingR2T
       MUST be set to 1.

 Julo


                                                                                                                                               
                      "Robert D.                                                                                                               
                      Russell"                 To:       ips@ece.cmu.edu                                                                       
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                      du>                      Subject:  RE: iSCSI: keys/parameter dependence                                                  
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                      06/06/2002 06:07                                                                                                         
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                      Please respond to                                                                                                        
                      "Robert D.                                                                                                               
                      Russell"                                                                                                                 
                                                                                                                                               
                                                                                                                                               



Julian:

I came across another dependency in draft 12-96 (but it has been
in the drafts for some time):

The end of section 11.20 says:

   "If ErrorRecoveryLevel is not 0 and if DataSequenceInOrder is set to
   Yes, a target may retry at most the last R2T, and an initiator may at
   most request retransmission for the last read data sequence.
   MaxOutstandingR2T MUST be set to 1 in this case."

It is unclear to me from reading this just what the "in this case"
refers to -- does it mean:

1) if MaxOutstandingR2T is not 1 then the target may not retry and
   the initiator may not request retransmission.

or

2) the combination ErrorRecoveryLevel > 0 and DataSequenceInOrder=Yes
   requires MaxOutStandingR2T=1.

If the first interpretation is correct, then this is not really a
dependency between the keys, but a subtle restriction on behavior
from a certain combination of keys.

If the second interpretation is correct, then this is a dependency
between keys.

Whichever interpretation is correct, I would suggest that the statement
in section 11.20 be reworded to make the interpretation unambiguous.

Thanks,
Bob Russell