Assistant Professor Mirella Amelia Mioc
Department of Computer Science
Faculty of Automatics and Computers
“Politehnica” University of Timisoara
Bd. V. Parvan nr. 2
Timisoara, 300223
ROMANIA
E-mail: mirella.mioc@cs.upt.ro

Abstract: All over the world in today’s global activities the continuous development of information technology has an important impact.
There are a lot of applications using shift registers in cryptography, coding theory and wireless system communication.
A Linear Feedback Shift Register is always the kernel of any digital system based on pseudorandom bits sequences.
Some important aspects are developed for working in Galois Fields using irreducible polynomials.
Such kind of methods are used more and more often in cryptosystems, convolutional codes, error correcting and detecting codes.
For example, the Advanced Encryption System (Rijndael) is based on using a grade 8 Irreducible Polynomials in a Galois Field.
Sometimes it’s necessary to choose between different scheme of shift registers generators of pseudorandom sequences. A comparison of functioning for such scheme is useful for a better understanding. For this goal there is the possibility to simulate the functioning with some programs or to experiment with a hardware model.
Both of these methods demonstrated that the Linear Feedback Shift Register and Multiple Input- Output Shift Register have the same function.
Based on the mathematical grounds, there are relations for calculating each of the weights of an irreducible polynomials.
Other aspects presented are focused on the convolutional codes.
The two complementary parts of a cryptosystem for coding and decoding offer a great variety of possibilities in choosing alternatives from cryptographic algorithms, as Rijndael, Reed-Solomon and other algorithms based on convolutional codes, as Viterbi.
Other aspects analised are in the frame of using Shift Registers in detecting and correcting communication errors.

Brief Biography of the Speaker:
Mirella Amelia Mioc graduated in 1981 the Faculty of Electrotehnics, Computer Science, of the „Traian Vuia” Polytehnic Institute of Timisoara;
Presently she is Assistant Professor in the Department of Computer Science from „Politehnica” University of Timisoara.
The main field of interest consists of analizing the use of shift registers in cryptography and coding theory, the subject of her PhD.
Her scientific activity concerns:
-Number theory;
-Numerical Methods for mathematics;
-Information Theory;
-Programming languages: Pascal, C, C++, Lisp, ML, Java;
-Fundamental concepts of programming languages;
-Study of using shift registers in cryptography and coding theory.
She is the author of:
-3 books about programming languages Pascal and C;
-4 guiding laboratories -numerical methods and programming languages ;
-25 scientific papers published in conference proceedings and journals in country and abroad.
She performed scientific activities in some foreign univesities:
-Technische Universitat Berlin, Germany
-Technical University of Budapest, Hungary;
-Universite Libre de Bruxelles, Belgium;
-Universite de Liege, Belgium;
-Universite Pierre et Marie Curie ( VI ) of Paris, France.
She participated in several EU founded projects in TEMPUS, LEONARDO and ERASMUS and also took part in some grants and agreements in research.