@techreport{OPUS4-20232,
  type      = {Working Paper},
  title     = {White Paper on Crowdsourced Network and QoE Measurements - Definitions, Use Cases and Challenges},
  editor    = {Hoßfeld, Tobias and Wunderer, Stefan},
  doi       = {10.25972/OPUS-20232},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202327},
  pages     = {24},
  year      = {2020},
  abstract  = {The goal of the white paper at hand is as follows. The definitions of the terms build a framework for discussions around the hype topic 'crowdsourcing'. This serves as a basis for differentiation and a consistent view from different perspectives on crowdsourced network measurements, with the goal to provide a commonly accepted definition in the community. The focus is on the context of mobile and fixed network operators, but also on measurements of different layers (network, application, user layer). In addition, the white paper shows the value of crowdsourcing for selected use cases, e.g., to improve QoE or regulatory issues. Finally, the major challenges and issues for researchers and practitioners are highlighted. This white paper is the outcome of the W{\"u}rzburg seminar on "Crowdsourced Network and QoE Measurements" which took place from 25-26 September 2019 in W{\"u}rzburg, Germany. International experts were invited from industry and academia. They are well known in their communities, having different backgrounds in crowdsourcing, mobile networks, network measurements, network performance, Quality of Service (QoS), and Quality of Experience (QoE). The discussions in the seminar focused on how crowdsourcing will support vendors, operators, and regulators to determine the Quality of Experience in new 5G networks that enable various new applications and network architectures. As a result of the discussions, the need for a white paper manifested, with the goal of providing a scientific discussion of the terms "crowdsourced network measurements" and "crowdsourced QoE measurements", describing relevant use cases for such crowdsourced data, and its underlying challenges. During the seminar, those main topics were identified, intensively discussed in break-out groups, and brought back into the plenum several times. The outcome of the seminar is this white paper at hand which is - to our knowledge - the first one covering the topic of crowdsourced network and QoE measurements.},
  subject      = {Crowdsourcing},
  language  = {en}
}
@phdthesis{Heck2005,
  author    = {Heck, Klaus},
  title     = {Wireless LAN performance studies in the context of 4G networks},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-14896},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2005},
  abstract  = {Wireless communication is nothing new. The first data transmissions based on electromagnetic waves have been successfully performed at the end of the 19th century. However, it took almost another century until the technology was ripe for mass market. The first mobile communication systems based on the transmission of digital data were introduced in the late 1980s. Within just a couple of years they have caused a revolution in the way people communicate. The number of cellular phones started to outnumber the fixed telephone lines in many countries and is still rising. New technologies in 3G systems, such as UMTS, allow higher data rates and support various kinds of multimedia services. Nevertheless, the end of the road in wireless communication is far from being reached. In the near future, the Internet and cellular phone systems are expected to be integrated to a new form of wireless system. Bandwidth requirements for a rich set of wireless services, e.g.\ video telephony, video streaming, online gaming, will be easily met. The transmission of voice data will just be another IP based service. On the other hand, building such a system is by far not an easy task. The problems in the development of the UMTS system showed the high complexity of wireless systems with support for bandwidth-hungry, IP-based services. But the technological challenges are just one difficulty. Telecommunication systems are planned on a world-wide basis, such that standard bodies, governments, institutions, hardware vendors, and service providers have to find agreements and compromises on a number of different topics. In this work, we provide the reader with a discussion of many of the topics involved in the planning of a Wireless LAN system that is capable of being integrated into the 4th generation mobile networks (4G) that is being discussed nowadays. Therefore, it has to be able to cope with interactive voice and video traffic while still offering high data rates for best effort traffic. Let us assume a scenario where a huge office complex is completely covered with Wireless LAN access points. Different antenna systems are applied in order to reduce the number of access points that are needed on the one hand, while optimizing the coverage on the other. No additional infrastructure is implemented. Our goal is to evaluate whether the Wireless LAN technology is capable of dealing with the various demands of such a scenario. First, each single access point has to be capable of supporting best-effort and Quality of Service (QoS) demanding applications simultaneously. The IT infrastructure in our scenario consists solely of Wireless LAN, such that it has to allow users surfing the Web, while others are involved in voice calls or video conferences. Then, there is the problem of overlapping cells. Users attached to one access point produce interference for others. However, the QoS support has to be maintained, which is not an easy task. Finally, there are nomadic users, which roam from one Wireless LAN cell to another even during a voice call. There are mechanisms in the standard that allow for mobility, but their capabilities for QoS support are yet to be studied. This shows the large number of unresolved issues when it comes to Wireless LAN in the context of 4G networks. In this work we want to tackle some of the problems.},
  subject      = {Drahtloses lokales Netz},
  language  = {en}
}
@misc{Feineis2008,
  type      = {Master Thesis},
  author    = {Feineis, Markus},
  title     = {Wortgenaue Annotation digitalisierter mittelalterlicher Handschriften},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30448},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2008},
  abstract  = {No abstract available},
  subject      = {Annotation},
  language  = {de}
}
@article{LohWamserPoigneeetal.2022,
  author    = {Loh, Frank and Wamser, Florian and Poign{\´e}e, Fabian and Geißler, Stefan and Hoßfeld, Tobias},
  title     = {YouTube Dataset on Mobile Streaming for Internet Traffic Modeling and Streaming Analysis},
  series = {Scientific Data},
  volume    = {9},
  journal   = {Scientific Data},
  number    = {1},
  doi       = {10.1038/s41597-022-01418-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300240},
  year      = {2022},
  abstract  = {Around 4.9 billion Internet users worldwide watch billions of hours of online video every day. As a result, streaming is by far the predominant type of traffic in communication networks. According to Google statistics, three out of five video views come from mobile devices. Thus, in view of the continuous technological advances in end devices and increasing mobile use, datasets for mobile streaming are indispensable in research but only sparsely dealt with in literature so far. With this public dataset, we provide 1,081 hours of time-synchronous video measurements at network, transport, and application layer with the native YouTube streaming client on mobile devices. The dataset includes 80 network scenarios with 171 different individual bandwidth settings measured in 5,181 runs with limited bandwidth, 1,939 runs with emulated 3 G/4 G traces, and 4,022 runs with pre-defined bandwidth changes. This corresponds to 332 GB video payload. We present the most relevant quality indicators for scientific use, i.e., initial playback delay, streaming video quality, adaptive video quality changes, video rebuffering events, and streaming phases.},
  language  = {en}
}
@article{CarolusWienrichToerkeetal.2021,
  author    = {Carolus, Astrid and Wienrich, Carolin and T{\"o}rke, Anna and Friedel, Tobias and Schwietering, Christian and Sperzel, Mareike},
  title     = {'Alexa, I feel for you!' Observers' empathetic reactions towards a conversational agent},
  series = {Frontiers in Computer Science},
  volume    = {3},
  journal   = {Frontiers in Computer Science},
  doi       = {10.3389/fcomp.2021.682982},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258807},
  year      = {2021},
  abstract  = {Conversational agents and smart speakers have grown in popularity offering a variety of options for use, which are available through intuitive speech operation. In contrast to the standard dyad of a single user and a device, voice-controlled operations can be observed by further attendees resulting in new, more social usage scenarios. Referring to the concept of 'media equation' and to research on the idea of 'computers as social actors,' which describes the potential of technology to trigger emotional reactions in users, this paper asks for the capacity of smart speakers to elicit empathy in observers of interactions. In a 2 × 2 online experiment, 140 participants watched a video of a man talking to an Amazon Echo either rudely or neutrally (factor 1), addressing it as 'Alexa' or 'Computer' (factor 2). Controlling for participants' trait empathy, the rude treatment results in participants' significantly higher ratings of empathy with the device, compared to the neutral treatment. The form of address had no significant effect. Results were independent of the participants' gender and usage experience indicating a rather universal effect, which confirms the basic idea of the media equation. Implications for users, developers and researchers were discussed in the light of (future) omnipresent voice-based technology interaction scenarios.},
  language  = {en}
}