Unformatted text preview: cern that there is a hidden agenda, such as laying the groundwork for a national public-key cryptosystem that is in fact vulnerable to being broken by NIST and/or NSA” . One serious question about the security of DSA was raised by Arjen Lenstra and Stuart Haber at Bellcore. This will be discussed later. 3. DSA is slower than RSA . True, more or less. Signature generation speeds are the same, but signature verification can be 10 to 40 times slower with DSA. Key generation, however, is faster. But key generation is irrelevant; a user rarely does it. On the other hand, signature verification is the most common operation. The problem with this criticism is that there are many ways to play with the test parameters, depending on the results you want. Precomputations can speed up DSA signature generation, but don’t always apply. Proponents of RSA use numbers optimized to make their calculations easier; proponents of DSA use their own optimizations. In any case, computers are getting faster all the time. While there is a speed difference, it will not be noticeable in most applications. 4. RSA is a de facto standard. Here are two examples of this complaint. From Robert Follett, the program director of standards at IBM : IBM is concerned that NIST has proposed a standard with a different digital signature scheme rather than adopting the international standard. We have been convinced by users and user organizations that the international standards using RSA will be a prerequisite to the sales of security products in the very near future. From Les Shroyer, vice president and director, corporate MIS and telecommunications, at Motorola : We must have a single, robust, politically-accepted digital signature standard that is usable throughout the world, between both U.S. and non-U.S., and Motorola and non-Motorola entities. The lack of other viable digital signature technology for the last eight years has made RSA a de facto standard.... Motorola and many other comp...
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- Fall '10
- Cryptography, Bruce Schneier, Applied Cryptography, EarthWeb, Search Search Tips