Area of Mathematics:Algebra and Geometry (EAG) Semester:6ο Course ID: 62203 Course Type:Elective Teaching hours per week: Theory: 4Practice: 0Laboratory: 0 ECTS :5 Eclass: Instructors: Description Bibliography Description Elementary number theory over the integers, key elements from ring theory, quotient ring, homomorphisms, ideals.The law of quadratic reciprocity, quadratic residues, Gauss sums.Field extensions, elements of Galois theory.The Frobenius operator, N-th roots of unity.Irreducible polynomials over finite fields, the cyclotomic reciprocity law, additive polynomials.Simple cryptosystems, Vigenere, Hill, permutation ciphers, stream ciphers. Cryptanalysis.Public key cryptosystems, RSA, baby step-giant step.Elliptic curves, point order, Mordel’s theorem.Elliptic cryptosystems, factorization with elliptic curves.Construction of elliptic curves of given order. Bibliography N. Koblitz. A Course in Number Theory and Cryptography, 2nd edition. Springer, 1994.