The discrete logarithm problem based on elliptic and hyperelliptic curves has gained a lot of popularity as a cryptographic primitive. The main reason is that no subexponential algorithm for computing discrete logarithms on small genus curves is currently available, except in very special cases. Therefore curve-based cryptosystems require much smaller key sizes than RSA to attain the same security level. This makes them particularly attractive for implementations on memory-restricted devices like smart cards and in high-security applications.

The Handbook of Elliptic and Hyperelliptic Curve Cryptography introduces the theory and algorithms involved in curve-based cryptography. After a very detailed exposition of the mathematical background, it provides ready-to-implement algorithms for the group operations and computation of pairings. It explores methods for point counting and constructing curves with the complex multiplication method and provides the algorithms in an explicit manner. It also surveys generic methods to compute discrete logarithms and details index calculus methods for hyperelliptic curves. For some special curves the discrete logarithm problem can be transferred to an easier one; the consequences are explained and suggestions for good choices are given. The authors present applications to protocols for discrete-logarithm-based systems (including bilinear structures) and explain the use of elliptic and hyperelliptic curves in factorization and primality proving. Two chapters explore their design and efficient implementations in smart cards. Practical and theoretical aspects of side-channel attacks and countermeasures and a chapter devoted to (pseudo-)random numbergeneration round off the exposition.

The broad coverage of all- important areas makes this book a complete handbook of elliptic and hyperelliptic curve cryptography and an invaluable reference to anyone interested in this exciting field.

The main topic of the volume is to develop efficient algorithms by which one can verify Artin's conjecture for odd two-dimensional representations in a fairly wide range. To do this, one has to determine the number of all representations with given Artin conductor and determinant and to compute the dimension of a corresponding space of cusp forms of weight 1 which is done by exploiting the explicit knowledge of the operation of Hecke operators on modular symbols.
It is hoped that the algorithms developed in the volume can be of use for many other problems related to modular forms.

The series is aimed specifically at publishing peer reviewed reviews and contributions presented at workshops and conferences. Each volume is associated with a particular conference, symposium or workshop. These events cover various topics within pure and applied mathematics and provide up-to-date coverage of new developments, methods and applications.

Die folgende Einflihrung in die Zahlentheorie entstand aus Vorlesungen, die- ich an der Universitiit des Saarlandes gehalten habe; sie urnfa t ziernlich genau den Stoff, der im Verlauf eines Wintersemesters im Rahmen der Vorlesung tiber "Elementare Zahlentheorie" behandelt wurde. Diese Vorlesung hat zwei Ziele: Einerseits sollen moglichst viele Studenten angesprochen werden, denen die Vorlesung "mathematische Allgemeinbil- dung" auf dem Gebiet der Zahlentheorie vermitteln soli; die fiir die Vor- Ie sung notwendigen Voraussetzungen z.B. auf dem Gebiet der Algebra sollen also moglichst gering sein. Tatsiichlich sollte die Kenntnis der algebraischen Grundstrukturen und ihrer elementarsten Eigenschaften geniigen; wenn an einigen Stellen etwas weitergehende Vberlegungen erforderlich sind, wird ver- sucht, diese an Ort und Stelle bereitzustellen. Der Abschnitt tiber abelsche Gruppen kann als Beispiel dazu dienen. Natiirlich mu man fiir diese Vor- gehen auch bezahlen, oft ersetzt das Rechnen zu Fu den eigentlich viel ein- leuchtenderen strukturellen Beweis, die lastigen Nachrechnungen bei Ver- kntipfungen von Restklassen sind ein deutliches Beispiel damr. Andererseits soli die Vorlesung interessierte Studenten auf die Algebraische Zahlentheorie vorbereiten; das Erreichen dieses Ziels sollte durch die Stoff- auswahl untersttitzt werden.