DANILO GLIGOROSKI
Danilo Gligoroski is a professor of Information Security and Cryptography at the Department of Telematics, at the Norwegian University of Science and Technology – Trondheim, Norway. He received his Ph.D. at the Cyril and Methodius’ University of Skopje in 1997 in the field of Computer Science. His research interests are Cryptography, Computer Security, Discrete algorithms, Information Theory and Coding.
BOTTLENECKS IN APPLIED DIGITAL SIGNATURES SCHEMES
A classical way for allocating bottlenecks in digital signature schemes is to measure the efficiency of the signing and the verification parts. For example, if the process is such that the company server receives a lot of signed transactions from individual clients and have to verify every signature, then an obvious choice would be to use a signature schneme that can do faster verification, while the individual signatures can be produced in a somewhat slower manner (RSA signatures with small public exponents have that property). On the other hand, if a company needs to send a bulk of signed invoices to hundreds of thousands (or millions) of users, then the signing speed is important (elliptical curve signature schemes are usually faster in signing than RSA or DSA signature schemes). However, with the advent of new standards and new technological advancements in medical equipment, especially in real-time teleradiology and mammography, the issue of whether the signing or verification is fast or slow does not at all influence the efficiency of the overall signature scheme. There, the speed of the used hash function is the real bottleneck, taking even up to 99.7% of the time spent on signing or verification. In his talk he will demonstrate several use case scenarios with several typical average sizes, starting from 16 KB (typical PDF files in financial transactions) up to files with a size of 160 MB – images obtained by mammographic scanners. Additionally, from the same perspective He will gives a what-if analysis that includes several new cryptographic hash functions from the ongoing SHA-3 competition.
