Re: NXT :: descendant of Bitcoin - Updated Information

Quote from: gimre on February 10, 2014, 01:27:31 PM

Quote from: ChuckOne on February 10, 2014, 11:19:11 AM

I think that's not the point here. Consider this:

Code:

b = f(a)

c = g(b)

d = h(a, c)

Let's assume c results in -2 with a certain b.

Even if c=-2 and c=3 are interchangeable mathematically, h might not work as expected as the pair (a, c) belong together.

So, it could be the case that h(a, -2) != h(a, 3) for the very same a. This must be avoided at any cost.

That IS the case, as h == verify, verify WORKS (validates) on "3" (and it SHOULD work on "3") and doesn't work on "-2",
(that's why you can see those "Generated incorrect block messages")

The point here is: 'SHOULD work on "3"' has to be proved.

Maybe, there are some negative numbers c so that (a, c') validates ALTHOUGH a is invalid. (where c' is the positive equivalent of c)
Maybe not.

So, proof of the algo as well as the code is needed.