Slovak University of Technology, Bratislava
Faculty of Electrical Engineering and Information Technology
Degree Course: INFORMATICS
Author: Bc. Tomá Tankó
Diploma thesis: Key stream generator based on the theory of generalized cyclotomy in Zpq
Supervisor: RNDr. Hana Lichardová, PhD.
The goal of this work has been to study the theory of generalized cyclotomic numbers, analyse generalized cyclotomic generator of order 2 and 4, design and implement the generalized cyclotomic generator of order 4. Finally, to check if the implemented generator resists the substitution of a generator of the same kind with different parameters.
We have implemented the generalized cyclotomic generator of order 4. Good cryptographical properties of generated sequences are ensured by choosing appropriate parameters of the generator.
On the base of experiments we have analysed the resistance of implemented generator. We have concluded that, in the case of short sequences, we are able to substitute the basic sequence with another up to length 25-30 elements. In the case of long sequences the implemented generator resists the substitution.