As explained in Section 5.1, U a can obtain [ h(ID i || x s ) ⊕ h(PW i ⊕ K i ) ⊕ K i ] using { g i, j i and e i } extracted [ 28, 29] from SC i, but he cannot obtain the random number K i. Besides, U a cannot obtain the random number R c using M3 = M1 ⊕ R c without having M1 (= h(x s || y s )) and U a fails to obtain M1 (= h(x s || y s )) as discussed in Section 5.1.
If U a extracts [ 28, 29] the values { c i, e i, g i, j i, h} from SC i, we explain in the following that he cannot obtain ID i of C i. To guess ID i from g i = (ID i ||PW i ) ⊕ f i and from j i = (ID i ||PW i ) ⊕ K i, the attacker must have the knowledge of {PW i, f i } and {PW i, K i }, respectively.
But U a cannot obtain f i from g i = (ID i ||PW i ) ⊕ f i as he does not know about user's identity ID i and password PW i.
Further U a cannot obtain K i from j i without knowing ID i and password PW i. Besides, U a cannot compute M1 a (= h(x s || y s )) = (c i ⊕ f i ) as he does not have access to f i.
A version of underdetermination that might threaten realism would thus assert that our postulated complete global theory of the world will have empirically equivalent alternatives with no translation from one to the other being possible, i.e. that we cannot obtain one from the other by reconstruing the predicates of the theory.
"If you do not accept the status quo -- which I do not -- and you cannot obtain an agreement on all the core issues," Mr. Eran said, "then the alternative is to go for a partial solution while keeping the ultimate political objectives of both sides in mind".
We have formerly demonstrated that this short-term culture model (i) cannot be obtained from normal colon tissue, (ii) is exclusively formed by epithelial cancer cells and (iii) is associated with tumour aggressiveness.
You and I cannot, to any degree, obtain the forms of wheat that were grown fifty years ago, let alone one hundred, one thousand, or ten thousand years ago. . . .
How can I ensure I obtain a good reference?
