3067
2009
eng
doctoralthesis
1
2009-08-20
--
2009-08-04
Performance Evaluation of Future Internet Applications and Emerging User Behavior
Leistungsbewertung von zukünftigen Internet-Applikationen und auftretenden Nutzerverhaltens
In future telecommunication systems, we observe an increasing diversity of access networks. The separation of transport services and applications or services leads to multi-network services, i.e., a future service has to work transparently to the underlying network infrastructure. Multi-network services with edge-based intelligence, like P2P file sharing or the Skype VoIP service, impose new traffic control paradigms on the future Internet. Such services adapt the amount of consumed bandwidth to reach different goals. A selfish behavior tries to keep the QoE of a single user above a certain level. Skype, for instance, repeats voice samples depending on the perceived end-to-end loss. From the viewpoint of a single user, the replication of voice data overcomes the degradation caused by packet loss and enables to maintain a certain QoE. The cost for this achievement is a higher amount of consumed bandwidth. However, if the packet loss is caused by congestion in the network, this additionally required bandwidth even worsens the network situation. Altruistic behavior, on the other side, would reduce the bandwidth consumption in such a way that the pressure on the network is released and thus the overall network performance is improved. In this monograph, we analyzed the impact of the overlay, P2P, and QoE paradigms in future Internet applications and the interactions from the observing user behavior. The shift of intelligence toward the edge is accompanied by a change in the emerging user behavior and traffic profile, as well as a change from multi-service networks to multi-networks services. In addition, edge-based intelligence may lead to a higher dynamics in the network topology, since the applications are often controlled by an overlay network, which can rapidly change in size and structure as new nodes can leave or join the overlay network in an entirely distributed manner. As a result, we found that the performance evaluation of such services provides new challenges, since novel key performance factors have to be first identified, like pollution of P2P systems, and appropriate models of the emerging user behavior are required, e.g. taking into account user impatience. As common denominator of the presented studies in this work, we focus on a user-centric view when evaluating the performance of future Internet applications. For a subscriber of a certain application or service, the perceived quality expressed as QoE will be the major criterion of the user's satisfaction with the network and service providers. We selected three different case studies and characterized the application's performance from the end user's point of view. Those are (1) cooperation in mobile P2P file sharing networks, (2) modeling of online TV recording services, and (3) QoE of edge-based VoIP applications. The user-centric approach facilitates the development of new mechanisms to overcome problems arising from the changing user behavior. An example is the proposed CycPriM cooperation strategy, which copes with selfish user behavior in mobile P2P file sharing system. An adequate mechanism has also been shown to be efficient in a heterogeneous B3G network with mobile users conducting vertical handovers between different wireless access technologies. The consideration of the user behavior and the user perceived quality guides to an appropriate modeling of future Internet applications. In the case of the online TV recording service, this enables the comparison between different technical realizations of the system, e.g. using server clusters or P2P technology, to properly dimension the installed network elements and to assess the costs for service providers. Technologies like P2P help to overcome phenomena like flash crowds and improve scalability compared to server clusters, which may get overloaded in such situations. Nevertheless, P2P technology invokes additional challenges and different user behavior to that seen in traditional client/server systems. Beside the willingness to share files and the churn of users, peers may be malicious and offer fake contents to disturb the data dissemination. Finally, the understanding and the quantification of QoE with respect to QoS degradations permits designing sophisticated edge-based applications. To this end, we identified and formulated the IQX hypothesis as an exponential interdependency between QoE and QoS parameters, which we validated for different examples. The appropriate modeling of the emerging user behavior taking into account the user's perceived quality and its interactions with the overlay and P2P paradigm will finally help to design future Internet applications.
Applikationen im heutigen Internet werden immer mehr durch intelligente Endknoten bereitgestellt, deren Kommunikation in logischen, virtuellen Netzwerken, (Overlays) realisiert wird. Die verstärkte Diensterbringung durch solche Overlays, wie zum Beispiel bei Peer-to-Peer Dateitauschbörsen oder Telefonie über das Internet, wird durch einen Paradigmenwechsel von Multi-Service Networks zu Multi-Network Services beschrieben. Während in einem Multi-Service Network verschiedene Dienste innerhalb eines Netzes angeboten werden, beschreibt ein Multi-Network Service die Diensterbringung über verschiedene Netze und Netzzugangstechnologien, wie es im Internet der Fall ist. Dadurch kann die technische Güte des Telekommunikationsdienstes (Quality of Service, QoS) nicht mehr die alleinige Metrik für die Qualität eines Dienstes sein. Stattdessen ist die vom Nutzer erfahrene Dienstgüte (User Perceived Quality of Experience, QoE) zu betrachten. Diese QoE muss entsprechend modelliert werden, um die Performanz von heutigen oder auch zukünftigen Internetapplikationen zu beurteilen. Die Berücksichtigung der QoE beinhaltet unter anderem auch neuartige Verhaltensweisen der Teilnehmer, die ebenfalls modelliert werden müssen. Ein Beispiel ist der Dienstabbruch durch ungeduldige Nutzer beim Herunterladen von Filmen oder bei nicht ausreichender Qualität bei Internet-Telefonie. Durch die Verschiebung der Intelligenz von Applikationen in Richtung Endknoten entstehen neu aufkommende Verhaltensweisen der Teilnehmer und sich ändernde Charakteristika des Netzwerkverkehrs, die sie von klassischen Client-Server-Anwendungen unterscheiden. Beispiele hierfür sind egoistisches oder altruistisches Nutzerverhalten bei der Einbringung von Endnutzer-Ressourcen zur Diensterbringung oder auch bösartiges Nutzerverhalten bei der gezielten Störung eines Dienstes (Pollution). In beiden Fällen sind die zeitdynamischen Verhaltensmuster (Churn, Flash Crowds) zu berücksichtigen. Um die ausgedehnten Overlay. Netze zu planen und zu evaluieren, sind überdies auch neue Leistungsbewertungsmodelle notwendig, damit zum Beispiel die Simulation skaliert oder aber auch zeitdynamische Nutzerverhalten in analytischen Modellen abgebildet wird. Diese Doktorarbeit arbeitet diese Aspekte an drei Anwendungsbeispielen auf: Verteilernetz für Dateiinhalte (Content Distribution Network), Netzwerk-basierte Videorekorder (Online TV Recorder) und Sprachtelefonie über P2P (VoP2P). Die Ergebnisse und Untersuchungen dieser Arbeit gliedern sich entsprechend dieser Anwendungsbeispiele.
urn:nbn:de:bvb:20-opus-37570
3757
10.25972/OPUS-3067
X122543
Tobias Hoßfeld
Würzburger Beiträge zur Leistungsbewertung Verteilter Systeme
01/09
deu
swd
Leistungsbewertung
deu
swd
Peer-to-Peer-Netz
deu
swd
Dienstgüte
deu
swd
Overlay-Netz
deu
swd
Mathematische Modellierung
deu
swd
BitTorrent
deu
swd
Skype
deu
swd
Warteschlangentheorie
deu
uncontrolled
zukünftiges Internet
deu
uncontrolled
vom Nutzer erfahrene Dienstgüte QoE
deu
uncontrolled
Multi-Netzwerk Dienste
deu
uncontrolled
intelligente Applikationen
deu
uncontrolled
Verteilung von Inhalten
eng
uncontrolled
Future Internet
eng
uncontrolled
Quality of Experience QoE
eng
uncontrolled
Multi-Network Service
eng
uncontrolled
Edge-based Intelligence
eng
uncontrolled
Content Distribution
Datenverarbeitung; Informatik
Network Architecture and Design
Network Protocols
Distributed Systems
Systems and Software
open_access
Institut für Informatik
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/3067/hossfeld_diss.pdf
4700
2010
eng
conferenceobject
Nokia Siemens Networks GmbH & Co. KG, Munich, Germany, DOCOMO Communications Laboratories Europe GmbH, Munich, Germany
1
2011-03-08
--
--
A Use Case Driven Approach to Network Virtualization
In today's Internet, services are very different in their requirements on the underlying transport network. In the future, this diversity will increase and it will be more difficult to accommodate all services in a single network. A possible approach to cope with this diversity within future networks is the introduction of support for running isolated networks for different services on top of a single shared physical substrate. This would also enable easy network management and ensure an economically sound operation. End-customers will readily adopt this approach as it enables new and innovative services without being expensive. In order to arrive at a concept that enables this kind of network, it needs to be designed around and constantly checked against realistic use cases. In this contribution, we present three use cases for future networks. We describe functional blocks of a virtual network architecture, which are necessary to support these use cases within the network. Furthermore, we discuss the interfaces needed between the functional blocks and consider standardization issues that arise in order to achieve a global consistent control and management structure of virtual networks.
urn:nbn:de:bvb:20-opus-55611
5561
Accepted at IEEE Kaleidoscope 2010
Dipl.-Inform. Daniel Schlosser
Deutsches Urheberrecht
Daniel Schlosser
Michael Jarschel
Michael Duelli
Tobias Hoßfeld
Klaus Hoffmann
Marco Hoffmann
Hans Jochen Morper
Dan Jurca
Ashiq Khan
deu
swd
Virtualisierung
deu
swd
Datenkommunikationsnetz
deu
swd
Internet
deu
swd
Rechnernetz
deu
uncontrolled
Anwendungsfall
deu
uncontrolled
Netzvirtualisierung
deu
uncontrolled
Standardisierung
eng
uncontrolled
Use case
eng
uncontrolled
network virtualization
eng
uncontrolled
future Internet architecture
eng
uncontrolled
standardization
Datenverarbeitung; Informatik
Systems and Software
open_access
Institut für Informatik
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/4700/Schlosser_Network_Virtualization.pdf
24112
2021
eng
12
21
article
1
--
2021-06-17
--
Uplink vs. Downlink: Machine Learning-Based Quality Prediction for HTTP Adaptive Video Streaming
Streaming video is responsible for the bulk of Internet traffic these days. For this reason, Internet providers and network operators try to make predictions and assessments about the streaming quality for an end user. Current monitoring solutions are based on a variety of different machine learning approaches. The challenge for providers and operators nowadays is that existing approaches require large amounts of data. In this work, the most relevant quality of experience metrics, i.e., the initial playback delay, the video streaming quality, video quality changes, and video rebuffering events, are examined using a voluminous data set of more than 13,000 YouTube video streaming runs that were collected with the native YouTube mobile app. Three Machine Learning models are developed and compared to estimate playback behavior based on uplink request information. The main focus has been on developing a lightweight approach using as few features and as little data as possible, while maintaining state-of-the-art performance.
Sensors
1424-8220
10.3390/s21124172
urn:nbn:de:bvb:20-opus-241121
2021-07-04T04:14:32+00:00
sword
swordwue
attachment; filename=deposit.zip
38aa389c01cf8507d1bcaac0f3814dd2
Sensors 2021, 21(12), 4172; https://doi.org/10.3390/s21124172
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Frank Loh
Fabian Poignée
Florian Wamser
Ferdinand Leidinger
Tobias Hoßfeld
eng
uncontrolled
HTTP adaptive video streaming
eng
uncontrolled
quality of experience prediction
eng
uncontrolled
machine learning
Datenverarbeitung; Informatik
open_access
Institut für Informatik
Import
Förderzeitraum 2021
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/24112/sensors-21-04172-v2.pdf
28415
2021
eng
215
232
2
1
article
1
--
2021-09-13
--
Valid statements by the crowd: statistical measures for precision in crowdsourced mobile measurements
Crowdsourced network measurements (CNMs) are becoming increasingly popular as they assess the performance of a mobile network from the end user's perspective on a large scale. Here, network measurements are performed directly on the end-users' devices, thus taking advantage of the real-world conditions end-users encounter. However, this type of uncontrolled measurement raises questions about its validity and reliability. The problem lies in the nature of this type of data collection. In CNMs, mobile network subscribers are involved to a large extent in the measurement process, and collect data themselves for the operator. The collection of data on user devices in arbitrary locations and at uncontrolled times requires means to ensure validity and reliability. To address this issue, our paper defines concepts and guidelines for analyzing the precision of CNMs; specifically, the number of measurements required to make valid statements. In addition to the formal definition of the aspect, we illustrate the problem and use an extensive sample data set to show possible assessment approaches. This data set consists of more than 20.4 million crowdsourced mobile measurements from across France, measured by a commercial data provider.
Network
2673-8732
10.3390/network1020013
urn:nbn:de:bvb:20-opus-284154
2022-09-03T16:34:12+00:00
sword
swordwue
attachment; filename=deposit.zip
ec89da92b2639b79bcc1b24c66bec6cb
Network (2021) 1:2, 215-232. https://doi.org/10.3390/network1020013
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Florian Wamser
Anika Seufert
Andrew Hall
Stefan Wunderer
Tobias Hoßfeld
eng
uncontrolled
mobile networks
eng
uncontrolled
crowdsourced measurements
eng
uncontrolled
statistical validity
Datenverarbeitung; Informatik
open_access
Institut für Informatik
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28415/network-01-00013-v2.pdf
28081
2022
eng
4
workingpaper
1
2022-07-25
--
--
Identification of Signaling Patterns in Mobile IoT Signaling Traffic
We attempt to identify sequences of signaling dialogs, to strengthen our understanding of the signaling behavior of IoT devices by examining a dataset containing over 270.000 distinct IoT devices whose signaling traffic has been observed over a 31-day period in a 2G network [4]. We propose a set of rules that allows the assembly of signaling dialogs into so-called sessions in order to identify common patterns and lay the foundation for future research in the areas of traffic modeling and anomaly detection.
Würzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)
urn:nbn:de:bvb:20-opus-280819
10.25972/OPUS-28081
publish
true
true
CC BY-SA: Creative-Commons-Lizenz: Namensnennung, Weitergabe unter gleichen Bedingungen 4.0 International
Viktoria Vomhoff
Stefan Geißler
Tobias Hoßfeld
deu
swd
Datennetz
eng
uncontrolled
IoT
Datenverarbeitung; Informatik
General Literature
open_access
Institut für Informatik
Arbeitspapiere (Working Paper)
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28081/Vornhoff_et_al_Signaling_Patterns_WueWoWas22_1570806856.pdf
28082
2022
eng
4
workingpaper
1
2022-07-25
--
--
LoRaWAN Network Planning in Smart Environments: Towards Reliability, Scalability, and Cost Reduction
The goal in this work is to present a guidance for LoRaWAN planning to improve overall reliability for message transmissions and scalability. At the end, the cost component is discussed. Therefore, a five step approach is presented that helps to plan a LoRaWAN deployment step by step: Based on the device locations, an initial gateway placement is suggested followed by in-depth frequency and channel access planning. After an initial planning phase, updates for channel access and the initial gateway planning is suggested that should also be done periodically during network operation. Since current gateway placement approaches are only studied with random channel access, there is a lot of potential in the cell planning phase. Furthermore, the performance of different channel access approaches is highly related on network load, and thus cell size and sensor density. Last, the influence of different cell planning ideas on expected costs are discussed.
Würzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)
urn:nbn:de:bvb:20-opus-280829
10.25972/OPUS-28082
publish
true
true
CC BY-SA: Creative-Commons-Lizenz: Namensnennung, Weitergabe unter gleichen Bedingungen 4.0 International
Frank Loh
Stefan Geißler
Tobias Hoßfeld
deu
swd
Datennetz
eng
uncontrolled
LoRaWan
Datenverarbeitung; Informatik
General Literature
open_access
Institut für Informatik
Arbeitspapiere (Working Paper)
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28082/Loh_et_al_LoRaWAN_WueWoWas22_1570807188.pdf
30241
2022
eng
2
22
article
1
--
2022-01-17
--
Towards LoRaWAN without data loss: studying the performance of different channel access approaches
The Long Range Wide Area Network (LoRaWAN) is one of the fastest growing Internet of Things (IoT) access protocols. It operates in the license free 868 MHz band and gives everyone the possibility to create their own small sensor networks. The drawback of this technology is often unscheduled or random channel access, which leads to message collisions and potential data loss. For that reason, recent literature studies alternative approaches for LoRaWAN channel access. In this work, state-of-the-art random channel access is compared with alternative approaches from the literature by means of collision probability. Furthermore, a time scheduled channel access methodology is presented to completely avoid collisions in LoRaWAN. For this approach, an exhaustive simulation study was conducted and the performance was evaluated with random access cross-traffic. In a general theoretical analysis the limits of the time scheduled approach are discussed to comply with duty cycle regulations in LoRaWAN.
Sensors
1424-8220
10.3390/s22020691
urn:nbn:de:bvb:20-opus-302418
2023-02-03T11:38:55+00:00
sword
swordwue
attachment; filename=deposit.zip
8b0691bbc46cfa791ace05973a733fdf
Sensors (2022) 22:2, 691. https://doi.org/10.3390/s22020691
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Frank Loh
Noah Mehling
Tobias Hoßfeld
eng
uncontrolled
LoRaWAN
eng
uncontrolled
IoT
eng
uncontrolled
channel management
eng
uncontrolled
scheduling
eng
uncontrolled
collision
Datenverarbeitung; Informatik
open_access
Institut für Informatik
Import
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/30241/sensors-22-00691-v2.pdf
28075
2022
eng
5
workingpaper
1
2022-07-25
--
--
Affordable Measurement Setups for Networking Device Latency with Sub-Microsecond Accuracy
This document presents a networking latency measurement setup that focuses on affordability and universal applicability, and can provide sub-microsecond accuracy. It explains the prerequisites, hardware choices, and considerations to respect during measurement. In addition, it discusses the necessity for exhaustive latency measurements when dealing with high availability and low latency requirements. Preliminary results show that the accuracy is within ±0.02 μs when used with the Intel I350-T2 network adapter.
Würzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)
urn:nbn:de:bvb:20-opus-280751
10.25972/OPUS-28075
publish
true
true
CC BY-SA: Creative-Commons-Lizenz: Namensnennung, Weitergabe unter gleichen Bedingungen 4.0 International
Alexej Grigorjew
Philip Diederich
Tobias Hoßfeld
Wolfgang Kellerer
deu
swd
Datennetz
eng
uncontrolled
latency
Datenverarbeitung; Informatik
General Literature
open_access
Institut für Informatik
Arbeitspapiere (Working Paper)
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28075/Grigorjew_et_al_Affordable_Measurement_WueWoWas22_1570809149.pdf
28080
2022
eng
4
workingpaper
1
2022-07-25
--
--
DBM: Decentralized Burst Mitigation for Self-Organizing LoRa Deployments
This work proposes a novel approach to disperse dense transmission intervals and reduce bursty traffic patterns without the need for centralized control. Furthermore, by keeping the mechanism as close to the Long Range Wide Area Network (LoRaWAN) standard as possible the suggested mechanism can be deployed within existing networks and can even be co-deployed with other devices.
Würzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)
urn:nbn:de:bvb:20-opus-280809
10.25972/OPUS-28080
publish
true
true
CC BY-SA: Creative-Commons-Lizenz: Namensnennung, Weitergabe unter gleichen Bedingungen 4.0 International
Simon Raffeck
Stefan Geißler
Tobias Hoßfeld
deu
swd
Datennetz
eng
uncontrolled
LoRa
Datenverarbeitung; Informatik
General Literature
open_access
Institut für Informatik
Arbeitspapiere (Working Paper)
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/28080/Raffeck_et_al_DBM_WueWoWas22_1570806855.pdf
30024
2022
eng
1
9
article
1
--
--
--
YouTube Dataset on Mobile Streaming for Internet Traffic Modeling and Streaming Analysis
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.
Scientific Data
10.1038/s41597-022-01418-y
urn:nbn:de:bvb:20-opus-300240
@articleLoh.2022, author = Loh, Frank and Wamser, Florian and Poignée, Fabian and Geißler, Stefan and Hoßfeld, Tobias, year = 2022, title = YouTube Dataset on Mobile Streaming for Internet Traffic Modeling and Streaming Analysis, volume = 9, number = 1, journal = Scientific Data, doi = 10.1038/s41597-022-01418-y
md5:9f1ddfdd2f495a5fc19de17b18ca7153
2023-01-19T07:09:31+00:00
/tmp/phpUmeu6F
bibtex
63c8ecab186f13.10219644
Scientific Data 2022, 9(1):293. DOI: 10.1038/s41597-022-01418-y
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Frank Loh
Florian Wamser
Fabian Poignée
Stefan Geißler
Tobias Hoßfeld
eng
uncontrolled
internet traffic
eng
uncontrolled
mobile streaming
eng
uncontrolled
YouTube
Datenverarbeitung; Informatik
open_access
Institut für Informatik
Förderzeitraum 2022
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/30024/Scientific_Data_Loh.pdf