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Re: SDSI syntax
>8) (maybe) allow strong negative assertions (jim is not an officer of
>foo-corp.) - sort of doable with groups, but this may be ungainly
Very good point. Negative caching is often more important than positive.
DNS works well largely because it keeps track of questions it has been
asked and cannot answer. I.e. if you request zorb.ai.mit.edu and it does
not exist then future requests for that address get answered locally,
there is no need to go off to ai.mit.edu for future queries.
I think that there are likely to be many cases where it will be desirable
to say "no" authoratatively.
There is a problem however. In my document signature scheme I deliberately used
only positive assertions to ensure that the system was monotonic (additional
assertions cannot contradict earlier ones). I suspect that Ron chose to avoid
negatives for similar reasons.
There may well be cases where one mifght wish to add in a negative assertion
when one knows that something is untrue. This is in some ways a revocation list
I suppose.
On a different topic, at what point would people find a face to face meeting to
discuss these issues helpfull (if at all)? Now is probably premature, but I'm
asking now because the month of June is probably the latest that one could be
held before September. Is there an concentration of east coast/ west coast
contributors that would make a meeting possible? I ask now because I was in
another group where four of us communicated by email for two years before
finding out that we were actualy living in a 6 mile radius.
Phill
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