24 research outputs found
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Message transfer framework for mobile devices using bluetooth low energy
textDespite the increasing availability of mobile devices offering handheld peer to peer communication capabilities, interoperability between heterogeneous mobile device platforms is hampered by the security requirements of their underlying operating systems. Bluetooth Low Energy (BLE) was introduced so that mobile devices could read from sensors with fewer security requirements, presenting an opportunity to allow disparate devices to connect and transfer data. This paper presents a message transfer framework to facilitate arbitrary data transfer using the GATT mechanisms as provided by BLE in the Bluetooth 4.0 specification. The provided implementation library and applications for Android along with a proof of concept application for iOS 8 sustain reliable transfer speeds of 1 KB/s, allowing for a 100KB payload (a small picture, for example) to be sent wirelessly between an Android and iOS device in just over a minute.Electrical and Computer Engineerin
Communication Architecture For Distributed Interactive Simulation (CADIS): Rationale Document Draft
Report is concerned with the necessary communication system protocol data unit standards which must be accepted and adopted for supporting distributed interactive simulation
Klausurtagung des Instituts für Telematik. Mainz 29.-31. März 1998
Der Bericht gibt einen Überblick über aktuelle
Forschungsarbeiten des Instituts für Telematik der Universität
Karlsruhe in den Bereichen Hochleistungskommunikation, verteilte
Systeme, Cooperation&Management und Telekooperation. Er ist in
zwei Teile gegliedert. Der erste beschreibt die persönlichen
Interessensgebiete der wissenschaftlichen Mitarbeiter. Danach folgt
eine Darstellung der Kooperationsprojekte des Instituts. Im Anhang
finden sich aktuelle Eigenveröffentlichungen der Mitarbeiter des
Instituts.
Der Tagungsband entstand im Rahmen der siebten Klausurtagung des
Instituts für Telematik, die vom 29. bis zum 31. März 1998 in
Mainz abgehalten wurde
Quality of service management for non-guaranteed networks
The increasing dominance of multimedia communication posed new requirements for the underlying systems. Multimedia data, formally called continuous media, has time constraints that impose real time limitations for their transmission. Certain levels of service, called Quality of Service (QoS), need to be considered when handling continuous media. The present work utilizes QoS concepts for networks that do not have inherent QoS support. The thesis aims at verifying the possibility of having QoS-controlled communication on non-guaranteed networks. A basic QoS architecture is designed where already existing QoS concepts are adapted to work with non-guaranteed networks. The architecture provides the facilities of QoS specification, mapping, admission, maintenance, monitoring and notification. In addition, a new concept for predictive QoS admission is introduced. The proposed architecture was verified using a prototype system. The results showed an increased percentage of continuous media that arrive on time to their receivers (good put) with higher network loads. The increased good put was at the expense of high network overhead
Application-oriented spatial graph grammars
The Reserved Graph Grammar (RGG) is a general graph grammar formalism that expresses a wide range of visual languages. This paper presents an extension to RGG with the capability of spatial specification. Graph transformation satisfying the spatial specification can be performed in the process of parsing. The RGG with spatial specification can be applied to various types of applications. The paper demonstrates an example for mathematical expression recognition
MAFTIA Conceptual Model and Architecture
This document builds on the work reported in MAFTIA deliverable D1. It contains a refinement of the MAFTIA conceptual model and a discussion of the MAFTIA architecture. It also introduces the work done in WP6 on verification and assessment of security properties, which is reported on in more detail in MAFTIA deliverable D
Netzwerkmanagement und Hochgeschwindigkeits- Kommunikation. Teil XVIII. Seminar SS 98
Der vorliegende Interne Bericht enthält die Beiträge zum Seminar
"Netzwerk-Management und Hochgeschwindigkeits-Kommunikation", das im
Sommersemester 1998 zum achtzehnten Mal stattgefunden hat.
Die Themenauswahl kann grob in folgende 3 Blöcke gegliedert werden:
1. Der erste Block ist Fragen der effizienten Kommunikation mittels ATM
(Asynchronous Transfer Mode) gewidmet. Dabei stehen Vorschläge für eine
Verbesserung der Handhabung von Gruppenkommunikation sowie Verfahren für
sogenannte parallele Pfade im Vordergrund. Ein weiterer Beitrag in diesem Block
erläutert ein integriertes Modell zur benutzergerechten Unterstützung der
Dienstgüte in ATM-Netzen. Weiterhin wird eine Technik vorgestellt, um
IP-basierte Kommunikation mittels ATM-Switching effizienter zu gestalten.
2. Ein zweiter Block behandelt Verfahren zur Unterstützung der Dienstgüte im IP
basierten Internet. Ein Ansatz beschäftigt sich mit der Problematik, dienstgü-
teunterstützende Mechanismen auch im LAN-Bereich zur Verfügung zu stellen. Ein
weiterer Ansatz definiert Konzepte, um eine möglichst einfach und schnell zu
realisierende Unterstützung von Diensten mit unterschiedlicher Charakteristiken
zu erreichen.
3. Der dritte Block umfasst den Themenbereich Sicherheit im Internet. Es werden
mehrere Protokolle vorgestellt und verglichen, die zur Schlüsselverwaltung in
der IP-Sicherheitsarchitektur dienen
Conceptual Model and Architecture of MAFTIA
This deliverable builds on the work reported in [MAFTIA 2000] and [Powell and Stroud 2001]. It contains a further refinement of the MAFTIA conceptual model and a revised discussion of the MAFTIA architecture. It also introduces the work done in MAFTIA on verification and assessment of security properties, which is reported on in more detail in [Adelsbach and Creese 2003
Seamless multimedia delivery within a heterogeneous wireless networks environment: are we there yet?
The increasing popularity of live video streaming from mobile devices such as Facebook Live, Instagram Stories, Snapchat, etc. pressurises the network operators to increase the capacity of their networks. However, a simple increase in system capacity will not be enough without considering the provisioning of Quality of Experience (QoE) as the basis for network control, customer loyalty and retention rate and thus increase in network operators revenue. As QoE is gaining strong momentum especially with increasing users’ quality expectations, the focus is now on proposing innovative solutions to enable QoE when delivering video content over heterogeneous wireless networks. In this context, this paper presents an overview of multimedia delivery solutions, identifies the problems and provides a comprehensive classification of related state-of-the-art approaches following three key directions: adaptation, energy efficiency and multipath content delivery. Discussions, challenges and open issues on the seamless multimedia provisioning faced by the current and next generation of wireless networks are also provided