Re: Some strawman ideas concerning <ds:Transforms>

Hi,

Pratik Datta wrote:
> I would like to see if we can achieve this streaming hint with forward 
> compatibility.
>   
+1 to at least trying to achieve that.
> By that I mean, we put in the hint in such a place that older implementations 
> can still verify such a signature by ignoring the hint, whereas newer 
> implementations can take advantage of this hint and do streaming.
>   
Quick Proposal:

        <ds:Reference URI="">
            <?ds:Reference dereference as event stream allowed,
constrained transforms enforced, legacy equivalent processing and
compatible results are hereby stipulated ?>
            <ds:Transforms>
              ...
            </ds:Transforms>
            <ds:DigestMethod Algorithm="..."/>
            <ds:DigestValue>...</ds:DigestValue>
        </ds:Reference>

If  the hints / preconditions are not fulfilled by the ds:Transforms,
throw an error.
> [...] how about adding it as a new attribute to an existing transform?  
> Implementations will probably ignore unknown attributes. Or maybe add a new 
> transformation parameter?
>   
I doubt that extension points will be ignored by applications in
general, hence my preference for a processing-instruction.

Konrad

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