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A question about the Object identifier type length
determinant coding - Standard
ISO/CEI 8825-2 (1996) understanding problem :
How to encode a length determinant ?
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ISO/CEI 8825-2 (1996) standard specifies in the 23
chapter how to encode an
Object identifier type. It is declared that a "n"
value length determinant
encoding precedes the whole object field-list
encoding. Moreover, it
is specified that "n" must be encoded as a semi
constrained whole number octet
count.
In the chapter 10.7, about the encoding of a
semi-constrained whole number,
it is written in 10.7.2 what to do in order to encode,
but the "lower bound"
value : lb need to be known. Normaly, the type
notation has determined the "lb"
value. But no information is specified about the lb
value in the ISO/CEI
8824-1 (1996) nore in the ISO/CEI 8825-2 (1996) 23
chapter.
What is the lb value ?
Can we consider the 10.7.4 treatment ?
The 10.7.4 specifies that the ("n" -"lb") value shall
be encoded as a non-
negative-binary-integer in an octet-aligned-bit-field
with the minimum number
of octets as specified in 10.3.
In my present case, "n" = 5.
I would like to be certain that the best mean to code
the length determinant in
this case, is to encode it on only one octet with:
00000101.
All information that may help me about these problems
is welcome.
Sincerely,
Laurent ROBERT
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