Abstract: Elliptic curve cryptosystems allow the use of prime fields with special prime moduli that speed up the finite field arithmetic considerably. Two algorithms for reduction with respect to special moduli have been implemented in software on both a 32-bit and a 64-bit platform and compared to well-known generic modular reduction methods. Timing results for multiplications in prime fields of size between 2^191 and 2^512 are presented and discussed.

Abstract: This book constitutes the refereed proceedings of the Second International Workshop on Multimedia Databases and Image Communication, MDIC 2001, held in Amalfi, Italy, in September 2001. The 16 revised full papers presented together with two invited papers were carefully reviewed and selected for inclusion in the book. The papers are organised in topical sections on image and visual computing applications, multimedia technology, image and visual information querying and browsing, and video indexing and communication.

Abstract: This paper presents an inexpensive cluster-based QoS networking testbed that can be employed to \emulate" different networks for multimedia communication ex-periments. Such a network can be built using standard PC and Ethernet hardware and open-source software components, e.g., IP routing and traÆc control avail- able in recent Linux kernels as well as a Differentiated Services package built atop these building blocks. The testbed can exibly be configured to model various link bandwidths as well as IP routers capable of classifying, queuing (with various disciplines), forward-ing and/or dropping packets and shaping traÆc. The QoS components and facilities of the testbed are in-troduced and initial performance analysis experiments and results are reported. A simple video streaming application under QoS control is presented to show the usefulness of the testbed.

Abstract: The workshop investigated, to what extent can component technology help to enhance the quality of distributed multimedia systems. Especially, to what extent can we achieve better reuse of multimedia content, reuse of code, interoperability, portability and performance. All authors agreed upon the necessity of building distributed multimedia systems of components as opposed to monolithic systems. The granularity of the components is an open issue, it can be stated, however, that most contributors presented solutions with rather heavy-weight components. Some of the presentations required explicitly standardization of multimedia formats, both for content and meta data. Most presenters touched the topic of multimedia-aware standardized middleware. Available middleware standards still do not support to a sufficient extent techniques to provide a guaranteed quality of service, and fit thus not well to be used for distributed multimedia. Multimedia system providers are often not interested to publish their interfaces. Thus, even if the internal design is component-oriented, the rest of the world has not much gain from this. Academic research can push openness and have a positive influence on industry. KEYWORDS Distributed Multimedia Systems, Quality of Service, Middleware, Component based Distributed Multimedia Systems, Adaptivity.