Adaptive Media Streaming to Mobile Devices: Challenges, Enhancements, and Recommendations

Video streaming is predicted to become the dominating traffic in mobile broadband networks. At the same time, adaptive HTTP streaming is developing into the preferred way of streaming media over the Internet. In this paper, we evaluate how different components of a streaming system can be optimized when serving content to mobile devices in particular. We first analyze the media traffic from a Norwegian network and media provider. Based on our findings, we outline benefits and challenges for HTTP streaming, on the sender and the receiver side, and we investigate how HTTP-based streaming affects server performance. Furthermore, we discuss various aspects of efficient coding of the video segments from both performance and user perception point of view. The final part of the paper studies efficient adaptation and delivery to mobile devices over wireless networks. We experimentally evaluate and improve adaptation strategies, multilink solutions, and bandwidth prediction techniques. Based on the results from our evaluations, we make recommendations for how an adaptive streaming system should handle mobile devices. Small changes, or simple awareness of how users perceive quality, can often have large effects

Adaptive Bitrate Video Streaming over HTTP in Mobile Wireless Networks

The thesis is produced by Akademika publishing merely in connection with the thesis defence. Kindly direct all inquiries regarding the thesis to the copyright The topic of this dissertation is bitrate adaptive media streaming to receivers in mobile wireless networks. This work was motivated by the recent explosion in popularity of media streaming to mobile devices. Wireless networks will always be bandwidth limited compared to fixed networks due to background noise, limited frequency spectrum, and varying degrees of network coverage and signal strength. Consequently, applications that need to move large amounts of data in a timely manner cannot simply assume that future networks will have sufficient bandwidth at all times. It is therefore important to make the applications themselves able to cope with varying degrees of connectivity. In order to understand the requirements of streaming in 3G mobile networks, we perform a large number of measurements in Telenor’s 3G network in and around Oslo. Using bandwidth traces from these field experiments, we compare commercia

in Experimental Particle Physics

Scientific progress has traditionally been driven forward by the efforts of individual experimentalists and theorists, but the highly complex challenges in today’s science and increasingly powerful technology calls for new methods and tools: Computation, data analysis and collaboration has become essential in most modern sciences. But despite that computer power, data storage, and communication continue to improve exponentially, computational resources are failing to keep up with scientists ’ demands. The purpose of this thesis is to study and develop new systems for computation that will make better use of the resources we have. This thesis will attempt to accomplish this goal by bridging the gap between a local resource management system called Condor and a Grid middleware called ARC that was developed under the NorduGrid project. The culmination of this work is the successful application of the unified Condor/ARC system in the highly demanding ATLAS Data Challenges

Ten Years of Household Micro Data. What Have We Learned?

Administrative register data for Norwegian households are used to analyse the distribution of debt and assets by income, wealth and age group. We find that the cross-sectional distribution is skewed. The distribution of debt across age has changed over time, with more of the debt being held by older households and less by younger ones. A birth-cohort study shows that households in later cohorts have more real debt than households in earlier cohorts when we compare the same life-cycle phase. Credit risk is evaluated using a number of measures and criteria. The overall conclusion is that the share of risky debt is small, but the share may increase significantly if interest rates climb to higher levels or house prices fall

Cultural identity and womens motivation in the Pomak's minority

Artikkelen presenterer utviklingen i etterspørsel etter kreditt og kredittpraksis fra norske banker siden 2008, slik de er representert i Norges Banks utlånsundersøkelse. Norske banker har rapportert om en betydelig innstramming i kredittpraksis i denne perioden. Norges Banks utlånsundersøkelse gir innsikt i årsakene til denne innstrammingen og på hvilken måte bankene har endret sine lånebetingelser. Det var en betydelig innstramming i kredittpraksis mot foretakene under finanskrisen i 2008-2009, mens innstrammingen i kredittpraksis mot husholdningene har kommet mer gradvis, og i stor grad som respons på nye krav og reguleringer fra myndighetene. Vi finner at strammere lånebetingelser rettet mot husholdningene har påvirket kredittveksten i denne sektoren