Final Assignment

The final reading assignment concerns itself with what has been hailed recently as the "future" of not only cryptology, but all of computing. Namely, the use of quantum mechanics to somehow create a quantum computer which operates on a completely different premise than that of normal computers. Though the quantum mechanics are somewhat complicated, the basic premise of the system is the utilization of the "spins" or orientations of subatomic particles to represent unique information. The challenge for this system of computing is that there is not currently a known way to consistently and accurately measure these subatomic particles without changing the states that they are in and thus changing the data.

If quantum computing can be realized, however, it represents an almost unimaginable leap in computing power because it allows for computations to be done parralell to one another rather than sequentially. Thus, if a problem can be broken into parts, each part can be computed simultaneously rather than in order to develop a massively faster machine. This would lead to the brute force attack becoming much more feasible and would effectively eliminate el gamal and RSA as viable cryptosystems. Quantum computers would, however, be able to use their new power towards the application of more advanced cryptosystems and the "battle between cryptology and cryptanalysis" would suppossedly continue.

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Chapter five deals with the advanced encryption standard Rijndael which is an encryption system based on symmetric key standards meant to replace DES which has recently been deemed as too insecure for commercial use. Rijndael was one of many finalists basically elicited due to a competition. Thus, the algorithm is perhaps not perfect and, as the book mentions, the other four finalists may be used in future crypto-systems. Rinndael, aside from having difficult computation, is based on the application of rounds, 10 for a 128 byte, otherwise 12 or 14 for other variations. The application was somewhat difficult to understand because it involves basically four different encryptions: the three transformations and then an XOR operation.

The significant part of this reading is mainly that this is a departure from the public key cryptosystems and indicates that despite the effectiveness of RSA and el gamal systems, symmetric key cryptosystems are still more efficient and cost effective than the public key counterparts. Rijndael is a block-cipher, indicating that this is still the preferred method of encryption for symmetric systems and, hopefully will be improved upon to make a truly secure symmetric system other than a one time pad.