Hi Leonard,
good to have you on the list !
>> I would like to distinct he pretty printing stuff mentioned above and
>> the crypto content made visible and hopefully computer processable from
>> a printed instance.
>>
> We've seen a couple of attempts at this as well - but none that would
> actually work on complex document types like those that can be
> represented by
> PDF. The problem, of course, is the canonicalization of the
> content. How can
> you recreate the electronic content "byte for byte" to match the
> data stream
> that was fed into the hash originally?
Don't worry, the 2D bar code works quite well ! The conductors on the
train scan the code 'on the fly' and I've seen no scanning problems,
even at 250 km/h. I guess there is a bunch of travel data within the bar
code and the human readable part doesn't needs scanning. Anyway : This
works quite well !
I'm not quite familiar with Konrad's use case, maybe he noticed the
problems you mentioned ...
[..]
>
>> If there is a signature field within the
>> given PDF document, we can do the crypto stuff on it. That's it ! We
>> don't need to care about all the PDF layers, dictionaries, versions of
>> forms ...
>>
> Oh, but were it that simple ;).
>
> What about documents you wish to sign that don't have the
> necessary fields
> already present? What about multiple signature workflows? What
> about author
> vs. certifying signatures (or even more interesting, a document
> containing
> both!)?
Oh yes, these are all the problems I like to shy away from ! Remember
the 'please sign here ...' example :
- The required fields MUST be present !
- The request must include some information about the signature to sign
( well, that's a common problem with XMLDSig ). We'll have to find a way
to identify the intended field for signing.
The DSS implementation should care about things it's designed for :
Signing et al.
Leave form handling and PDF creation to the PDF experts !
Greetings
Andreas
___________________________________________________
Andreas Kühne
phone: +49 177 293 24 97
mailto:
Trustable Ltd.
Niederlassung Deutschland
Ströverstr. 18 - 59427 Unna
Amtsgericht Hamm HRB 5868
Directors
Andreas Kühne
Heiko Veit
Company UK
Company No: 5218868
Registered in England and Wales
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Ende der Originalnachricht
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___________________________________________________
Andreas Kühne
phone: +49 177 293 24 97
mailto:
Trustable Ltd.
Niederlassung Deutschland
Ströverstr. 18 - 59427 Unna
Amtsgericht Hamm HRB 5868
Directors
Andreas Kühne
Heiko Veit
Company UK
Company No: 5218868
Registered in England and Wales
