Re: iSCSI: DefaultTime2Wait

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

Bob,

You are right - I will fix it - the text was changed to reflect the fact that the is no "god that holds the function" selection but a selection by the responder that has to respect the rule and yes there is an error at this specific key.

I will attempt your suggested format.

Julo

"Robert D. Russell" <rdr@io.iol.unh.edu> 06/29/2002 01:26 PM Please respond to "Robert D. Russell"

To:        Julian Satran/Haifa/IBM@IBMIL         cc:                 Subject:        iSCSI: DefaultTime2Wait

Julian:

There is another unexplained change between drafts 12 and 13 in
Section 11.16 DefaultTime2Wait

In draft 12 this section contained the sentence:
   "The higher of the two values is selected."
which means that the selection rule for DefaultTime2Wait is "maximum".

In draft 13 this same section contains the sentence:
   "The responder MUST select a value that does not exceed
   the offered value."
which means that the selection rule for DefaultTime2Wait is "minimum".

Again since there was no discussion of this change on the mailing list,
and since it is not listed in the change log, I assume it is another
cut-and-paste error and that the sentence in draft 13 section 11.16
should read:
   "The responder MUST select a value that is not less than
   the offered value."
so that the selection rule for DefaultTime2Wait remains "maximum".

Correct?


There is also a minor typo in Draft 13 Section 11.17 DefaultTime2Retain.
It currently contains the sentence:
    "The responder MUST select a value that does not
      greater the offered value."
Clearly "greater" should be "exceed".


These typos bring up another point about clarification, since there
are minor inconsistencies in the way identical selection rules are
expressed.

The following are all the non-declarative simple-value numeric keys
in draft 13 and the current statement of their selection rules (with
the above corrections for DefaultTime2Wait and DefaultTime2Retain):

11.2  MaxConnections - "The lower of the two numbers is selected."
11.14 MaxBurstSize - "The responder MUST select a value that does not
      exceed the offered value."
11.15 FirstBurstSize - "The responder MUST select a value that does not
      exceed the offered value."
11.16 DefaultTime2Wait - "The responder MUST select a value that is not
      less than the offered value."
11.17 DefaultTime2Retain - "The responder MUST select a value that does not
      exceed the offered value."
11.18 MaxOutstandingR2T - "The responder MUST select a value that does not
      exceed the offered value."
11.21 ErrorRecoveryLevel - "The responder MUST select a value that does not
      exceed the offered value."

I would suggest revising the text for all numerical keys to follow
the model already used for Boolean keys, and that is for each key
to always immediately follow the line stating:
    Default is <value>.
with a line stating:
    Result function is <maximum or minimum>.
This makes it less wordy, more precise and unambiguous.


As a final editorial clarification, since the text in section 4.2.2
"Simple-value negotiations" talks about "the selection rule specific
to the key", perhaps "Result function" in all key descriptions should
be changed to "Selection rule" for consistency.

Thanks for your consideration.


Bob Russell
InterOperability Lab
University of New Hampshire
rdr@iol.unh.edu
603-862-3774