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    RE: Section 4.1 clarifications



    Julo,
    
    > The integer representation was discussed a long time ago on the
    > list and it was decided that decimal should be allowed as it might
    > be copied from some human readable tables. I would hate to make
    > this type of changes this late.
    
    I agree that decimal encoding should be retained for NUMERIC CONSTANTS, for
    the reasons you state.  However, I do not believe it makes any sense to
    allow decimal representations of BINARY ITEMS.
    
    I think a concrete example might help here.  I am in the process of
    implementing CHAP authentication.  Section 10.5 of the spec states that
    CHAP_A and CHAP_I are "numbers" and CHAP_C and CHAP_R are "binary items and
    their binary length (not the length of the character string that represents
    them in encoded form) MUST not exceed 1024 bytes."
    
    When I parse CHAP_A and CHAP_I, which I'm calling "numeric constants," I'll
    allow decimal or hexadecimal representations, but I certainly won't be able
    to cope with a number whose decoded value is wider than 4 bytes . . . and I
    doubt that anyone else will, either.  [Let's face the fact that unless they
    are explicitly told to expect decoded values longer than, say, 4 bytes,
    implementers will use stroul() or its equivalent in a situation like this.]
    
    When I parse CHAP_C and CHAP_R, which I'm calling "binary items," I expect
    numbers whose decoded values could be up to 1024 bytes long.  I can easily
    convert hexadecimal or base-64 representations of such values into binary
    data; however, I WILL NOT be able to cope with decimal encoding, which in
    this case could have up to 2,467 digits . . . and I doubt that anyone else
    will, either.  (The "human readable tables" argument goes out the window in
    this case as well . . . who will be typing those 2,467 decimal digits?)
    
    As the wording of Section 10.5 already shows, there is a need to make a
    distinction between "numeric constants" ("numbers") and "binary items."  I
    am only suggesting that this be done consistently throughout the spec, with
    a single clear definition for each term.
    
    Michael
    
    --
    Michael J. Krueger              mailto:michael.krueger@windriver.com
    Wind River Networks                         http://www.windriver.com
    500 Wind River Way                               phone: 510-749-2130
    Alameda, CA  94501                                 fax: 510-749-2010
    


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Last updated: Thu Apr 25 17:18:27 2002
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