Author: fermineutronfermineutron
Date: Nov 10, 2006 16:48
Most experts argue that the quantum computers (QC) will require change
of assimetric key encryption systems. That is, the factorng of a large
number will no longer be a diffucult problem, since QC will be able to
use all possible values for prime numbers simmultaneously hence
yeilding correct pair which factors a given long number in several
clock cycles.
Now it seems to me that the problems with using cryptography when
attacker has a QM will not stop there. It is customary o assume that
attacker knows the encription algorythm and can intercept lots of data
encrypted with the same key as the messege he is trying to decrypt.
So if attacker is trying to breake encrypted text E2 and has plain text
T1 and its encrypted version E1, using the same key as used for E2, all
attaker has to do is to find a key which decrypts E1 into T1. If
quantum computers can do basic math they also can do more complex
operations, which will take loger, but will just like basic math use
all possible input output values simmultaneously, hence atacker can use
all possible keys in 1 operation (here operation is not a clock cycle
but a time required to do 1 encryption) to encrypt T1 into En and see
which En=E1, hence yeilding the key for E2.
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