Multimedia-Streaming in Benutzergruppen

At the time being, multimedia services using IP technology like IPTV or video on-demand are a hot topic. Technically, they can be classified under the notion of streaming. A server sends media data in a continuous fashion to one or several clients, which consume and display data portions as soon as they arrive. Using a feedback channel customers may influence the play-back, watching programs time-shifted or pausing the program. An enhancement of such streaming services is to watch those movies with a group of people on several devices in parallel. Similar approaches have been developed using IP multicast. However, users cannot control the presentation: pausing or skipping of more unimportant parts is impossible. Moreover, members cannot be added to the session directly within the application. The costream architecture developed in this works offers a collaborative streaming service without these limitations: People may join others watching a movie or invite others to such a collaborative streaming session. Dependent on the desired course of the session the participants' control operations are executed for all users, or the group is split into subgroups to let watchers follow their own time-lines. A group management controls this by means of user roles. Separate from the group management, the so-called association service provides for streaming session control and synchronization among participants. This separation of duties is advantageous in the sense that standard components can be used: For group management, SIP conferencing servers are suitable, whereas session control can best be handled using RTSP proxies as already used for caching of media data. Eventually, the evaluation of this architecture shows that such a service offers both low latency for clients and an acceptable synchronization of media streams to different client devices. Moreover, the communication overhead compared to usual conferencing or streaming systems is very low.Mit Hilfe der IP-Technologie erbrachte Multimedia-Dienste wie IPTV oder Video-on-Demand sind zur Zeit ein gefragtes Thema. Technisch werden solche Dienste unter dem Begriff "Streaming" eingeordnet. Ein Server sendet Mediendaten kontinuierlich an Empfänger, welche die Daten sofort weiterverarbeiten und anzeigen. Über einen Rückkanal hat der Kunde die Möglichkeit der Einflussnahme auf die Wiedergabe. Eine Weiterentwicklung dieser Streaming-Dienste ist die Möglichkeit, gemeinsam mit anderen denselben Film auf mehreren Geräten anzusehen. Ähnliche Ansätze gibt es im Internet bereits durch IP-Multicast. Allerdings können Benutzer hierbei keinen Einfluss auf die Übertragung nehmen - das Überspringen von Teilen ist zum Beispiel nicht möglich. Andere Benutzer können nicht direkt zur Streaming-Sitzung eingeladen werden. Collaborative Streaming ohne solche Einschränkungen bietet die in dieser Arbeit entwickelte costream-Architektur: Sie erlaubt es, andere zum gemeinsamen Betrachten eines Filmes einzuladen oder sich selbst in eine Benutzergruppe einzuklinken. Abhängig vom gewünschten Ablauf der Sitzung wird die Steuerung für alle Teilnehmer durchgeführt oder die Gruppe aufgeteilt. Eine Gruppenverwaltung regelt dies mit Hilfe von Rollenzuweisungen. Davon getrennt sorgt eine weitere Komponente für die Steuerung der Streaming-Sitzungen und die Synchronisation zwischen Teilnehmern. Diese Aufteilung hat den Vorteil, dass von der IETF entwickelte Standardprotokolle eingesetzt werden können. Für die Gruppenverwaltung sind SIP-Konferenzsysteme geeignet, während für die Sitzungssteuerung ein RTSP-Zwischensystem benutzt wurde. Die Evaluierung dieser Architektur zeigt schließlich, dass ein solcher Dienst nicht nur geringe Wartezeiten aufweist, sondern eine akzeptable Synchronisation der Datenströme auf die verschiedenen Ausgabegeräte der Benutzer erreicht wird. Zudem ist der Zusatzaufwand verglichen mit üblichen Konferenz- oder Streaming-Systemen sehr gering

College Catalog, 2012-2013, Graduate

https://digitalcommons.buffalostate.edu/buffstatecatalogs/1222/thumbnail.jp

College Catalog, 2016-2017, Graduate

https://digitalcommons.buffalostate.edu/buffstatecatalogs/1230/thumbnail.jp

College Catalog, 2015-2016, Graduate

https://digitalcommons.buffalostate.edu/buffstatecatalogs/1228/thumbnail.jp

Undergraduate Catalogue 2005-2007

https://scholarship.shu.edu/undergraduate_catalogues/1005/thumbnail.jp

Integrating Wireless Sensor Networks and Mobile Ad-hoc NETworks for enhanced value-added services

In some situations where the standard telecommunication infrastructure is not available, Mobile Ad hoc NETworks (MANETs) can be deployed to provide the required communication. These networks are established "on the fly" without a need for prior communication organization and are composed of autonomous mobile devices, such as cell phones, PDAs or laptops. In similar conditions, such as in emergency response operations, integrating MANETs and Wireless Sensor Networks (WSNs) can notably enhance the MANET participant's end-user experience. WSNs sense and aggregate ambient information, such as physiological, environmental or physical data related to a nearby phenomenon. The integration, which provides end-user availability to WSN required information, is feasible via gateways. However, when the ambient information collected by WSNs is intended for applications residing in MANETs, centralized and fixed gateways are not practicably feasible. This is mainly due to ad-hoc nature, lack of centralized control and constraints on the end-user devices that are used in MANETs. These devices are usually limited in power and capacity and cannot host centralized gateways. In this thesis we exploit the integration of WSN and MANET in order to provide novel value-added services which enhance the end-user experience of MANET participants. Motivating scenarios are introduced, background information is presented, requirements are derived and the state of the art regarding the integration of WSN with existing networks, including MANETs, is evaluated. Based on the evaluation, none of the existing solutions satisfies all of our derived requirements. Therefore, we propose an overall two-level overlay architecture to integrate WSNs (with mobile sinks) and MANETs. This architecture is based on the distributed gateway and applications which form the P2P overlays. Overlays are application-layer networks which are created on top of the exiting MANET. To interconnect gateway and application overlays we derive corresponding requirements and evaluate the existing approaches. Since none of these approaches fulfills all of our requirements, we propose protocols, mechanisms and design corresponding modules for the interconnection of overlays. Finally we refine our overall architecture based on the interconnection aspects. As a proof of concept, we implement a prototype for the inter-overlay information exchange. This implementation is based on SIP extensions and uses two existing P2P middlewares. We also simulate our prototype using Oversim simulation tool and collect experimental results. Based on these results, we can see that our architecture is a valid and promising approach for interconnecting different P2P overlays and can be deployed to provide the overall solution for WSN and MANET integrated system

La Salle University Undergraduate Catalog 2004-2005

https://digitalcommons.lasalle.edu/course_catalogs/1179/thumbnail.jp

ACUTA Journal of Telecommunications in Higher Education

In This Issue Campus Wireless Needs; DAS lssues to Consider Dead Duck: Don\u27t Let the Next Flap Over Social Media Be Yours New Law Requires Fire Reporting ADVERTORIAL: Centurylink Cloud-Based Services The Never-Ending Conundrum of lllegal Student Downloads Technology and Privacy on the 21st-Century Campus Great Expectations: Cloud Computing Fail to Plan?...Plan to Fail President\u27s Message From the lnterim Executive Director Q&A with the CI

Graduate Catalogue 2007-2009

https://digitalscholarship.tnstate.edu/graduatecatalogues/1000/thumbnail.jp

Undergraduate Catalogue 2007-2008

https://scholarship.shu.edu/undergraduate_catalogues/1003/thumbnail.jp