On Tue, 2004-10-05 at 04:48, Tony Finch wrote:
On Tue, 5 Oct 2004, John Levine wrote:
We don't understand the scaling issues of any callback scheme, because
nobody's ever tried one on a large scale. Having done my PhD thesis
on databases, I have a reasonably good idea what's involved in
building a database that has the very high update rate that a callback
database needs, and it's a hard problem, since update performance
scales much worse than linearly and is hard to parallelize.
Where does this large update rate come from? Most (all?) of the tag
schemes we have discussed can be verified statelessly, and they don't
have to have per-user data so scaling to hundreds of thousands of users
isn't necessarily a problem either.
Would there be an advantage having a scheme that offered some level of
replay protection when a bounce is detected by way of the signature?
-Doug