The types of communication (central, semi-central, peripheral) Specification of the gnutella-protocol (PING, PONG, QUERY, QUERY-HIT, PUSH - packets) The graphical user interface Limewire and its class structure / Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze und verteilte Systeme der Fakultaet fuer Informatik der TU Chemnitz. Vergleich zentrale, semizentrale und dezentrale Kommunikation, Spezifikation eines P2P-Protokolls des Gnutella-Netzes (PING, PONG, QUERY, QUERY-HIT, PUSH - Pakete) Die graphische Oberflaeche Limewire und deren Struktur

At IAV GmbH, Chemnitz, an embedded platform for high-performance sensor data acquisition has been developed. Sensor data is gathered and preprocessed by two digital signal processors (DSP) which communicate bidirectionally via dual-ported memory with the central controlling instance, a Freescale MCF5484 microcontroller running uClinux. The goal of this thesis is to design, implement, analyze and optimize a real-time communication protocol between both DSPs and the microcontroller. The challenges of this thesis can be defined as follows: • A uClinux driver for the dual-ported RAM must be implemented. This driver has to employ the microcontroller’s internal DMA engine and should be integrated into the Linux kernel’s DMA framework. • The DMA engine must be thoroughly analyzed. Especially interesting is its behavior when concurrently performing data transfers. Potential influence factors onto data transfer performance and timing predictability should be experimentally identified and quantitatively characterized, if possible. • Sensor data from the DSPs to the microcontroller has to meet real-time demands and must be prioritized in some way over status and parameter data from and to the DSPs. • Correct and efficient synchronization is a must. If possible, different synchronization schemes should be compared to each other. • The achievable performance in terms of guaranteed and maximum data throughput between DSP and microcontroller as well as end-to-end bandwidth has to be estimated. • Apart from the DMA engine analysis, a general evaluation of potential and achieved performance, timing predictability and the remaining microcontroller’s processing capacity (if any) should be executed.

Univ., Thèse--Genève, 2006.

Stuttgart, Univ., Diplomarb., 2002.

Techn. Universiẗat, Diss., 2003--Hamburg.

No description available.

This assignment has been performed at location and commissioned by Attendit AB in Jönköping. The task has been to develop a client/server system to access data stored in SQL databases where the client application is developed to run on regular cellular telephones. The importance has been to develop as reliable mobile communication as possible. The functionality that is demanded upon the mobile communication is: • Secured for future versions • Interoperability • Data should not be bugged, modified or disappear unnoticed • Resource efficient We have achieved these demands by developing our own protocol that is on top of the TCP protocol. The difficulty with the development has been to take in mind the limited resources of the mobile phones regarding storage, memory and CPU. The result of this task is a working system with a belonging database which has stable mobile communication as foundation. Server and client is well structure so the system easy can be extended with new different calls to the database. In hence of confidentiality the real system is not presented in this report. Instead we will describe fictitious scenario to exemplify the resolutions to the problems that we have identified.

Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze und verteilte Systeme (Fakultaet fuer Informatik) der TU Chemnitz. Workshop-Thema: Infrastruktur der ¨Digitalen Universitaet¨ Zur unmittelbaren Kommunikation zweier oder mehrerer Kommunikationspartner werden heute sogenannte Instant Messaging Systeme eingesetzt. Der Vortrag zeigt zwei moegliche Ansaetze fuer ein Protokoll, das diese Art von Kommunikation bewerkstelligen kann. Zum einen handelt es sich um das Protokoll einer freien Implementierung eines IM Systems, Jabber. Zum anderen ist dies das Protokoll eines im Rahmen einer Diplomarbeit an der Fakultaet fuer Informatik entstandenen IM Systems, Locom.

The types of communication (central, semi-central, peripheral) Specification of the gnutella-protocol (PING, PONG, QUERY, QUERY-HIT, PUSH - packets) The graphical user interface Limewire and its class structure / Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur Rechnernetze und verteilte Systeme der Fakultaet fuer Informatik der TU Chemnitz. Vergleich zentrale, semizentrale und dezentrale Kommunikation, Spezifikation eines P2P-Protokolls des Gnutella-Netzes (PING, PONG, QUERY, QUERY-HIT, PUSH - Pakete) Die graphische Oberflaeche Limewire und deren Struktur

Workshop Mensch-Computer-Vernetzung Übersicht über die technischen Grundlagen von Web Services Abgrenzung zu anderen RPC-Mechanismen Beispiele für Beschreibungssprachen