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Re: IA5 String...



>>    There was a lot of energy around S/MIME. People are implementing
>> it. Internally, it's pretty kludgely, but it does provide pretty good
>> cryptographic services. (as an aside, my favorite kludge anecdote is
>> the fact that X.509 certificates use an IA5 character set rather than
>> ASCII, so that the @ in email addresses has to be represented as (a)
>> instead).
>
>Wow, is this true?  I dont think so.  The CCITT document I have (CCITT
>T.50) mentions that an @ sign (Commercial at) is a member of the IRV.
>>From what I understand IA5 basically means US ASCII.  
>
>Alex
>

If people are going to criticize X.509, they ought to at least get their facts 
straight, beginning with the difference between Printable String (standardized 
around the time of the IBM 1403 printer with its 48 character print chain) and 
some of the more extended alphabets. In particular, X.500 has been amended to 
include BMPString within DirectoryString, and BMPString is essentially Unicode. 
Now, there may be some who would argue that a 16 bit character isn't sufficient 
to represent every language in the galaxy (Old High Martian may have some 
additional requirements), but as a first approximation it should certainly good 
enough. 

And one of the virtues of ASN.1 is that a compliant implemtnation shouldn't 
have to be concerned with such details as the alphabet that is used.


Bob

Robert R. Jueneman
GTE Laboratories
40 Sylvan Road
Waltham, MA 02254
[email protected]
1-617/466-2820

"The opinions expressed are my own, and may not 
reflect the official position of GTE, if any, on this subject."