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Publications VS: Bibliography 2013 BibTeX

 
@inproceedings {INPROC-2013-67,
   author = {Simon Gansel and Stephan Schnitzer and Frank D{\"u}rr and Kurt Rothermel and Christian Maih{\"o}fer},
   title = {{Towards Virtualization Concepts for Novel Automotive HMI Systems}},
   booktitle = {Proceedings of 4th IFIP TC 10 International Embedded Systems Symposium, IESS 2013, Paderborn, Germany, June 17-19, 2013.},
   publisher = {Springer Berlin Heidelberg},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   series = {Embedded Systems: Design, Analysis and Verification},
   volume = {403},
   pages = {193--204},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   isbn = {978-3-642-38853-8},
   isbn = {10.1007/978-3-642-38853-8_18},
   keywords = {Virtualization; Automotive HMI},
   language = {English},
   cr-category = {H.5.2 Information Interfaces and Presentation User Interfaces,     J.7 Computers in Other Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-67/INPROC-2013-67.pdf,     http://link.springer.com/chapter/10.1007%2F978-3-642-38853-8_18},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Many innovations in the automotive industry are based on electronics and software, which has led to a steady increase of electronic control units (ECU) in cars. This brought up serious scalability and complexity issues in terms of cost, installation space, and energy consumption. In order to tackle these problems, there is a strong interest to consolidate ECUs using virtualization technologies. However, current efforts largely neglect legal constraints and certification issues and the resulting technical requirements. In this paper, we focus on the consolidation of graphics hardware through virtualization, which received a lot of interest in the car industry due to the growing relevance of HMI systems such as head unit and instrument cluster in modern cars. First, we investigate relevant ISO standards and legal requirements and derive seven technical requirements for a virtualized automotive HMI system. Based on these requirements, we present the concept for a Virtualized Automotive Graphics System (VAGS) that allows for the consolidation of mixed-criticality graphics ECUs.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-67&engl=1}
}
@inproceedings {INPROC-2013-62,
   author = {Kirak Hong and Beate Ottenw{\"a}lder and Umakishore Ramachandran},
   title = {{Scalable Spatio-temporal Analysis on Distributed Camera Networks}},
   booktitle = {Proceedings of the 7th International Symposium on Intelligent Distributed Computing (IDC 2013)},
   publisher = {Springer International Publishing},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   series = {Studies in Computational Intelligence},
   volume = {511},
   pages = {131--140},
   type = {Conference Paper},
   month = {September},
   year = {2013},
   doi = {10.1007/978-3-319-01571-2_16},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-62/INPROC-2013-62.pdf,     http://link.springer.com/chapter/10.1007/978-3-319-01571-2_16},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Technological advances and the low cost of sensors enable the deployment of large-scale camera networks in airports and metropolises. A well-known technique, called spatio-temporal analysis, enables detecting anomalies such as an individual entering into a restricted area without permission. Spatio-temporal analysis requires a large amount of system resources to infer locations of occupants in real-time. In particular, state update becomes a bottleneck due to computation and communication overhead to update possibly large application state. In this paper we propose a system design and mechanisms for scalable spatio-temporal analysis. We present a distributed system architecture including smart cameras and distributed worker nodes in the cloud to enable real-time spatio-temporal analysis on large-scale camera networks. Furthermore we propose and implement a couple of selective update mechanisms to further improve scalability of our system by reducing the communication cost for state update.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-62&engl=1}
}
@inproceedings {INPROC-2013-59,
   author = {Marius Wernke and Frank D{\"u}rr and Kurt Rothermel},
   title = {{Protecting Movement Trajectories through Fragmentation}},
   booktitle = {Proceedings of the Tenth Annual International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MobiQuitous '13)},
   address = {Tokyo, Japan},
   publisher = {ICST},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {1--12},
   type = {Conference Paper},
   month = {December},
   year = {2013},
   keywords = {Location based applications; position sharing; privacy},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-59/INPROC-2013-59.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Location-based applications (LBAs) like geo-social networks, points of interest finders, and real-time traffic monitoring applications have entered people's daily life. Advanced LBAs rely on location services (LSs) managing movement trajectories of multiple users in a scalable fashion. However, exposing trajectory information raises user privacy concerns, in particular if LSs are non-trusted. For instance, an attacker compromising an LS can use the retrieved user trajectory for stalking, mugging, or to trace user movement. To limit the misuse of trajectory data, we present a new approach for the secure management of trajectories on non-trusted servers. Instead of providing the complete trajectory of a user to a single LS, we split up the trajectory into a set of fragments and distribute the fragments among LSs of different providers. By distributing fragments, we avoid a single point of failure in case of compromised LSs, while different LBAs can still reconstruct the trajectory based on user-defined access rights. In our evaluation, we show the effectiveness of our approach by using real world trajectories and realistic attackers using map knowledge and statistical information to predict and reconstruct the user's movement. Location management, fragmentation, trajectories, privacy},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-59&engl=1}
}
@inproceedings {INPROC-2013-57,
   author = {Susanne Becker and Michael Peter and Dieter Fritsch and Damian Philipp and Patrick Baier and Christoph Dibak},
   title = {{Combined grammar for the modeling of building interiors}},
   booktitle = {ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences},
   address = {Kapstadt, S{\"u}dafrika},
   publisher = {International Society for Photogrammetry and Remote Sensing},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   series = {ISPRS Acquisition and Modelling of Indoor and Enclosed Environments},
   volume = {II-4/W1},
   pages = {1--6},
   type = {Conference Paper},
   month = {December},
   year = {2013},
   keywords = {Public Sensing; Opportunistic Sensing; Smartphone; Indoor; Mapping},
   language = {German},
   cr-category = {J.5 Arts and Humanities,     C.2.4 Distributed Systems},
   contact = {Susanne Becker susanne.becker@ifp.uni-stuttgart.de},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {As spatial grammars have proven successful and efficient to deliver LoD3 models, the next challenge is their extension to indoor applications, leading to LoD4 models. Therefore, a combined indoor grammar for the automatic generation of indoor models from erroneous and incomplete observation data is presented. In building interiors where inaccurate observation data is available, the grammar can be used to make the reconstruction process robust, and verify the reconstructed geometries. In unobserved building interiors, the grammar can generate hypotheses about possible indoor geometries matching the style of the rest of the building. The grammar combines concepts from L-systems and split grammars. It is designed in such way that it can be derived from observation data fully automatically. Thus, manual predefinitions of the grammar rules usually required to tune the grammar to a specific building style, become obsolete. The potential benefit of using our grammar as support for indoor modeling is evaluated based on an example where the grammar has been applied to automatically generate an indoor model from erroneous and incomplete traces gathered by foot-mounted MEMS/IMU positioning systems.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-57&engl=1}
}
@inproceedings {INPROC-2013-52,
   author = {Damian Philipp and Jaroslaw Stachowiak and Frank D{\"u}rr and Kurt Rothermel},
   title = {{Model-Driven Public Sensing in Sparse Networks}},
   booktitle = {Proceedings of the 10th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services},
   publisher = {Springer},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   series = {LNCS},
   pages = {1--12},
   type = {Conference Paper},
   month = {December},
   year = {2013},
   keywords = {model-driven; energy optimization; public sensing; opportunistic sensing; adaptive algorithm; mobility},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-52/INPROC-2013-52.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Public Sensing (PS) is a recent trend for building large-scale sensor data acquisition systems using commodity smartphones. Limiting the energy drain on participating devices is a major challenge for PS, as otherwise people will stop sharing their resources with the PS system. Existing solutions for limiting the energy drain through model-driven optimizations are limited to dense networks where there is a high probability for every point of interest to be covered by a smartphone. In this work, we present an adaptive model-driven PS system that deals with both dense and sparse networks. Our evaluations show that this approach improves data quality by up to 41 percentage points while enabling the system to run with a greatly reduced number of participating smartphones. Furthermore, we can save up to 81\% of energy for communication and sensing while providing data matching an error bound of 1°C up to 96\% of the time.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-52&engl=1}
}
@inproceedings {INPROC-2013-51,
   author = {Marius Wernke and Frank D{\"u}rr and Kurt Rothermel},
   title = {{Speed Protection Algorithms for Privacy-aware Location Management}},
   booktitle = {Proceedings of the IEEE 9th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob 2013).},
   address = {Lyon, France},
   publisher = {IEEE Xplore},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {355--362},
   type = {Conference Paper},
   month = {October},
   year = {2013},
   keywords = {Location-based applications; location-based services; speed protection; movement trajectory; location management; location privacy},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-51/INPROC-2013-51.pdf,     www.ieeexplore.ieee.org,     www.PriLoc.de},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Nowadays, millions of users share their complete movement trajectory online when using real-time traffic monitoring applications, pay-as-you-drive insurances, or when sharing their last road trip with friends. However, many users still hesitate to use location-based applications as they are not willing to reveal, for instance, their driving behavior or the occurrence of a speeding violation. Therefore, we present novel speed protection algorithms protecting users from revealing a violation of given speed limits when using location-based applications. Our algorithms support time-based and distance-based position updates. To protect positions indicating a speeding violation, we either adjust temporal information by delaying position updates or adjust their spatial information. We evaluate our algorithms by using real world traces and show that the protected movement trajectory of the user is of high quality even after removing speeding violations.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-51&engl=1}
}
@inproceedings {INPROC-2013-35,
   author = {Patrick Baier and Frank D{\"u}rr and Kurt Rothermel},
   title = {{Efficient Distribution of Sensing Queries in Public Sensing Systems}},
   booktitle = {Proceedings of the 10th IEEE International Conference on Mobile Ad-hoc and Sensor Systems (MASS 2013)},
   publisher = {IEEE Computer Society},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {1--9},
   type = {Conference Paper},
   month = {October},
   year = {2013},
   language = {German},
   cr-category = {C.2 Computer-Communication Networks},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-35/INPROC-2013-35.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {The advent of mobile phones paved the way for a new paradigm for gathering sensor data termed Public Sensing (PS). PS uses built-in sensors of mobile devices to opportunistically gather sensor data. For instance, the microphones of a crowd of mobile phones can be used to capture sound samples, which can be used to construct a city noise map. A great challenge of PS is to reduce the energy consumption of mobile devices since otherwise users might not be willing to participate. One crucial part in the overall power consumption is the energy required for the communication between the mobile devices and the infrastructure. In particular, the communication required for sending sensing queries to mobile devices has been largely neglected in the related work so far. Therefore, in this paper, we address the problem of minimizing communication costs for the distribution of sensing queries. While existing systems simply broadcast sensing queries to all devices, we use a selective strategy by addressing only a subset of devices. In order not to negatively affect the quality of sensing w.r.t. completeness, this subset is carefully chosen based on a probabilistic sensing model that defines the probability of mobile devices to successfully perform a given sensing query. Our evaluations show that with our optimized sensing query distribution, the energy consumption can be reduced by more than 70\% without significantly reducing the quality of sensing.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-35&engl=1}
}
@inproceedings {INPROC-2013-33,
   author = {Patrick Baier and Frank D{\"u}rr and Kurt Rothermel},
   title = {{Opportunistic Position Update Protocols for Mobile Devices}},
   booktitle = {Proceedings of the International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp 2013)},
   publisher = {ACM},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {1--9},
   type = {Conference Paper},
   month = {September},
   year = {2013},
   language = {English},
   cr-category = {C.2 Computer-Communication Networks},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-33/INPROC-2013-33.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Many location-based applications such as geo-social networks rely on location services storing mobile object positions. To update positions on location servers, position update protocols are used. On the one hand, these protocols decide when an update has to be sent to ensure a certain quality of position information. On the other hand, they try to minimize the energy consumption of the mobile device by reducing communication to a minimum. In this paper, we show how to improve the energy efficiency of different update protocols by taking the energy characteristics of the mobile network interface into account. In particular, we show that the energy consumption can be reduced on average by 70\% using an opportunistic update strategy sending position updates together with messages of other applications. We present a Markov model to predict the arrival of messages and an online optimization algorithm calculating an optimized schedule to send position updates.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-33&engl=1}
}
@inproceedings {INPROC-2013-31,
   author = {Kirak Hong and David Lillethun and Umakishore Ramachandran and Beate Ottenw{\"a}lder and Boris Koldehofe},
   title = {{Mobile Fog: A Programming Model for Large-Scale Applications on the Internet of Things}},
   booktitle = {Proceedings of the 2nd MCC Workshop on Mobile Cloud Computing},
   address = {Hong Kong, China},
   publisher = {ACM Press},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {15--20},
   type = {Conference Paper},
   month = {August},
   year = {2013},
   doi = {10.1145/2491266.2491270},
   keywords = {fog computing; cloud computing; programming model; Internet of Things; future Internet applications; situation awareness applications},
   language = {English},
   cr-category = {C.2.1 Network Architecture and Design,     C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-31/INPROC-2013-31.pdf,     http://doi.acm.org/10.1145/2491266.2491270},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {The ubiquitous deployment of mobile and sensor devices is creating a new environment, namely the Internet of Things(IoT), that enables a wide range of future Internet applications. In this work, we present Mobile Fog, a high level programming model for future Internet applications that are geospatially distributed, large-scale, and latency-sensitive. We analyze use cases for the programming model with camera network and connected vehicle applications to show the efficacy of Mobile Fog We also evaluate application performance through simulation.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-31&engl=1}
}
@inproceedings {INPROC-2013-29,
   author = {Kirak Hong and David Lillethun and Umakishore Ramachandran and Beate Ottenw{\"a}lder and Boris Koldehofe},
   title = {{Opportunistic Spatio-temporal Event Processing for Mobile Situation Awareness}},
   booktitle = {Proceedings of the 7th ACM International Conference on Distributed Event-Based Systems (DEBS)},
   address = {Arlington, Texas, USA},
   publisher = {ACM Press},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {195--206},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   doi = {10.1145/2488222.2488266},
   keywords = {mobility; complex event processing; situation awareness},
   language = {English},
   cr-category = {C.2.1 Network Architecture and Design,     C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-29/INPROC-2013-29.pdf,     http://doi.acm.org/10.1145/2488222.2488266},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {With the proliferation of mobile devices and sensors, mobile situation awareness is becoming an important class of applications. The key requirement of this class of applications is low-latency processing of events stemming from sensordata in order to provide timely situational information to mobile users.To satisfy the latency requirement, we propose a spatio-temporal event processing system that uses prediction-based continuous query handling. Our system predicts future query regions for moving consumers and starts processing events early so that the live situational information is available when the consumer reaches the future location. In contrast to existing systems, our system provides timely information about a consumer's current position by hiding computation latency for processing recent events. To evaluate our system, we measure the quality of results and timeliness of live situational information with various query parameters. Our evaluation shows that we can achieve highly meaningful query results with near-zero latency in most cases.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-29&engl=1}
}
@inproceedings {INPROC-2013-28,
   author = {Beate Ottenw{\"a}lder and Boris Koldehofe and Kurt Rothermel and Umakishore Ramachandran},
   title = {{MigCEP: Operator Migration for Mobility Driven Distributed Complex Event Processing}},
   booktitle = {Proceedings of the 7th ACM International Conference on Distributed Event-Based Systems (DEBS)},
   address = {Arlington, Texas, USA},
   publisher = {ACM Press},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {183--194},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   doi = {10.1145/2488222.2488265},
   keywords = {complex event processing; migration; mobility},
   language = {English},
   cr-category = {C.2.1 Network Architecture and Design,     C.2.4 Distributed Systems,     E.1 Data Structures},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-28/INPROC-2013-28.pdf,     http://doi.acm.org/10.1145/2488222.2488265},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {A recent trend in communication networks --- sometimes referred to as fog computing --- offers to execute computational tasks close to the access points of the networks. This enables real-time applications, like mobile Complex Event Processing (CEP), to significantly reduce end-to-end latencies and bandwidth usage. Most work studying the placement of operators in such an environment completely disregards the migration costs. However, the mobility of users requires frequent migration of operators, together with possibly large state information, to meet latency restrictions and save bandwidth in the infrastructure. This paper presents a placement and migration method for providers of infrastructures that incorporate cloud and fog resources. It ensures application-defined end-to-end latency restrictions and reduces the network utilization by planning the migration ahead of time. Furthermore, we present how the application knowledge of the CEP system can be used to improve current live migration techniques for Virtual Machines to reduce the required bandwidth during the migration. Our evaluations show that we safe up to 49\% of the network utilization with perfect knowledge about a users mobility pattern and up to 27\% of the network utilization when considering the uncertainty of those patterns.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-28&engl=1}
}
@inproceedings {INPROC-2013-27,
   author = {Boris Koldehofe and Frank D{\"u}rr and Muhammad Adnan Tariq},
   title = {{Event-based Systems Meet Software-defined Networking}},
   booktitle = {Proceedings of the 7th ACM International Conference on Distributed Event-Based Systems (DEBS)},
   publisher = {ACM},
   institution = {University of Stuttgart, Faculty of Computer Science, Germany},
   pages = {271--280},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   doi = {10.1145/2488222.2488270},
   keywords = {Software-defined Networking, Event-based Systems, Content-based Routing, Publish/Subscribe, Network Virtualization},
   language = {English},
   cr-category = {C.2.1 Network Architecture and Design,     C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-27/INPROC-2013-27.pdf,     http://dx.doi.org/10.1145/2488222.2488270},
   department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Distributed Systems},
   abstract = {Software-defined networking (SDN) is a recent development in the area of communication networks with tremendous support by key players building the next generation of computer hardware and software. This development will have significant impact on how communication middleware---in particular, future distributed event-based systems---can be designed. While currently the communication middleware has no possibility to directly influence the properties of its underlying communication channels on the network layer, SDN enables communication middleware to control and flexibly adapt the forwarding of communication flows in the underlying network. In addition to the immediate implication to local area networks such as data center networks, campus networks, or company networks, novel trends like network virtualization may even support Internet-wide distributed applications to benefit from SDN in the future. This paper gives an introduction on how to utilize SDN-concepts for improving the performance of event-based middleware and to test their behavior.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-27&engl=1}
}
@inproceedings {INPROC-2013-26,
   author = {Boris Koldehofe and Ruben Mayer and Umakishore Ramachandran and Kurt Rothermel and Marco V{\"o}lz},
   title = {{Rollback-Recovery without Checkpoints in Distributed Event Processing Systems}},
   booktitle = {Proceedings of the 7th ACM International Conference on Distributed Event-Based Systems (DEBS)},
   publisher = {ACM},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {27--38},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   doi = {10.1145/2488222.2488259},
   keywords = {Reliability; Recovery; Complex Event Processing},
   language = {English},
   cr-category = {C.2.4 Distributed Systems,     C.4 Performance of Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-26/INPROC-2013-26.pdf,     http://dx.doi.org/10.1145/2488222.2488259},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Reliability is of critical importance to many applications involving distributed event processing systems. Especially the use of stateful operators makes it challenging to provide efficient recovery from failures and to ensure consistent event streams. Even during failure-free execution, state-of-the-art methods for achieving reliability incur significant overhead at run-time concerning computational resources, event traffic, and event detection time. This paper proposes a novel method for rollback-recovery that allows for recovery from multiple simultaneous operator failures, but eliminates the need for persistent checkpoints. Thereby, the operator state is preserved in savepoints at points in time when its execution solely depends on the state of incoming event streams which are reproducible by predecessor operators. We propose an expressive event processing model to determine savepoints and algorithms for their coordination in a distributed operator network. Evaluations show that very low overhead at failure-free execution in comparison to other approaches is achieved.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-26&engl=1}
}
@inproceedings {INPROC-2013-23,
   author = {Muhammad Adnan Tariq and Boris Koldehofe and Kurt Rothermel},
   title = {{Efficient content-based routing with network topology inference}},
   booktitle = {Proceedings of the 7th ACM International Conference on Distributed Event-Based Systems (DEBS)},
   address = {Arlington, Texas, USA},
   publisher = {ACM},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {51--62},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   doi = {10.1145/2488222.2488262},
   keywords = {QoS; quality of service; network inference; underlay awareness; delay; bandwidth; content-based; publish/subscribe; event-based},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-23/INPROC-2013-23.pdf,     http://doi.acm.org/10.1145/2488222.2488262},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Content-based publish/subscribe has gained high popularity for large-scale dissemination of dynamic content. Yet it is highly challenging to enable communication-efficient dissemination of content in such systems, especially in the absence of a broker infrastructure. This paper presents a novel approach that exploits the knowledge of event traffic, user subscriptions and topology of the underlying physical network to perform efficient routing in a publish/subscribe system. In particular, mechanisms are developed to discover the underlay topology among subscribers and publishers in a distributed manner. The information of the topology and the proximity between the subscribers to receive similar events is then used to construct a routing overlay with low communication cost. Our evaluations show that for internet-like topologies the proposed inference mechanisms are capable of modeling an underlay in an efficient and accurate manner. Furthermore, the approach yields a significant reduction in routing cost in comparison to the state of the art.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-23&engl=1}
}
@inproceedings {INPROC-2013-22,
   author = {Frank D{\"u}rr},
   title = {{Improving the Efficiency of Cloud Infrastructures with Elastic Tandem Machines}},
   booktitle = {Proceedings of the 6th International Conference on Cloud Computing (Cloud 2013)},
   address = {Santa Clara, CA, USA},
   publisher = {IEEE Computer Society},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {1--8},
   type = {Conference Paper},
   month = {June},
   year = {2013},
   keywords = {cloud computing; infrastructure as a service; efficiency; energy, elasticity; scaling; system on a chip; software-defined networking; green computing},
   language = {English},
   cr-category = {C.2.3 Network Operations,     C.2.4 Distributed Systems,     C.2.1 Network Architecture and Design,     C.4 Performance of Systems,     C.5 Computer System Implementation,     H.3.4 Information Storage and Retrieval Systems and Software},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-22/INPROC-2013-22.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {In this paper, we propose a concept for improving the energy efficiency and resource utilization of cloud infrastructures by combining the benefits of heterogeneous machine instances. The basic idea is to integrate low-power system on a chip (SoC) machines and high-power virtual machine instances into so-called Elastic Tandem Machine Instances (ETMI). The low-power machine serves low load and is always running to ensure the availability of the ETMI. When load rises, the ETMI scales up automatically by starting the high-power instance and handing over traffic to it. For the non-disruptive transition from low-power to high-power machines and vice versa, we present a handover mechanism based on software-defined networking technologies. Our evaluations show the applicability of low-power SoC machines to serve low load efficiently as well as the desired scalability properties of ETMIs.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-22&engl=1}
}
@inproceedings {INPROC-2013-04,
   author = {Damian Philipp and Jaroslaw Stachowiak and Patrick Alt and Frank D{\"u}rr and Kurt Rothermel},
   title = {{DrOPS: Model-Driven Optimization for Public Sensing Systems}},
   booktitle = {2013 IEEE International Conference on Pervasive Computing and Communications (PerCom 2013)},
   address = {San Diego, CA, USA},
   publisher = {IEEE Computer Society},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {185--192},
   type = {Conference Paper},
   month = {March},
   year = {2013},
   doi = {10.1109/PerCom.2013.6526731},
   keywords = {Data acquisition; Distributed computing; Wireless sensor networks; Public Sensing; Opportunistic Sensing; Smartphone; Model-Driven Data Acquisition; Quality aware; Adaptive, autonomic and context-aware computing; Energy-efficient and green pervasive computing; Innovative pervasive computing applications; Pervasive opportunistic communications and applications; Participatory, opportunistic and social sensing; Sensors and RFID in pervasive systems; Smart devices and intelligent environments},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-04/INPROC-2013-04.pdf,     http://www.comnsense.de,     http://dx.doi.org/10.1109/PerCom.2013.6526731},
   contact = {Damian Philipp damian.philipp@ipvs.uni-stuttgart.de},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {The proliferation of modern smartphones has given rise to Public Sensing, a new paradigm for data acquisition systems utilizing smartphones of mobile participants. In this paper, we present DrOPS, a system for improving the efficiency of data acquisition in Public Sensing systems. DrOPS utilizes a model-driven approach, where the number of required readings from mobile smartphones is reduced by inferring readings from the model. Furthermore, the model can be used to infer readings for positions where no sensor is available. The model is directly constructed from the observed phenomenon in an online fashion. Using such models together with a client-specified quality bound, we can significantly reduce the effort for data acquisition while still reporting data of required quality to the client. To this effect, we develop a set of online learning and control algorithms to create and validate the model of the observed phenomenon and present a sensing task execution system utilizing our algorithms in this paper. Our evaluations show that we obtain models in a matter of just hours or even minutes. Using the model-driven approach for optimizing the data acquisition, we can save up to 80\% of energy for communication and provide inferred temperature readings for uncovered positions matching an error-bound of 1°C up to 100\% of the time.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-04&engl=1}
}
@inproceedings {INPROC-2013-01,
   author = {Bj{\"o}rn Schilling and Boris Koldehofe and Kurt Rothermel and Umakishore Ramachandran},
   title = {{Access Policy Consolidation for Complex Event Processing}},
   booktitle = {IEEE Conference on Networked Systems (NetSys)},
   publisher = {IEEE},
   institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany},
   pages = {92--101},
   type = {Conference Paper},
   month = {March},
   year = {2013},
   doi = {10.1109/NetSys.2013.18},
   keywords = {Event processing; Complex event processing; CEP; Security; Access Control; Bayesian network},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2013-01/INPROC-2013-01.pdf},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {In distributed complex event processing, event streams are processed over a chain of subsequent operators. For large-scale applications like a logistic chain these operators may be hosted by different entities and thus are spread over different security domains. Current approaches for complex event processing cannot preserve the privacy of an operator’s incoming event streams. An adversary may infer the original input stream from its legally received event streams. In this paper we present a fine-grained access management for complex event processing. We show how to enforce privacy of events throughout the chain of dependent operators by specifying appropriate access policies and proposing an algorithm for policy consolidation. Furthermore, we introduce the calculation of obfuscation achieved in a correlation step. This allows us to ignore access requirements once a sufficient obfuscation level has been achieved, the proposed algorithms is capable to reduce the required overhead in the enforcement of access policies. We prove correctness and evaluate the cost in establishing policy consolidation.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2013-01&engl=1}
}
@article {ART-2013-13,
   author = {Hannes Wolf and Klaus Herrmann and Kurt Rothermel},
   title = {{Dealing with uncertainty: Robust workflow navigation in the healthcare domain}},
   journal = {ACM Transactions on Intelligent Systems and Technology (TIST)},
   address = {New York, NY, USA},
   publisher = {ACM},
   volume = {4},
   number = {4},
   type = {Article in Journal},
   month = {September},
   year = {2013},
   doi = {10.1145/2508037.2508046},
   issn = {2157-6904},
   language = {English},
   cr-category = {C.2.4 Distributed Systems,     H.4.1 Office Automation},
   ee = {http://doi.acm.org/10.1145/2508037.2508046},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Processes in the healthcare domain are characterized by coarsely predefined recurring procedures that are flexibly adapted by the personnel to suite-specific situations. In this setting, a workflow management system that gives guidance and documents the personnel's actions can lead to a higher quality of care, fewer mistakes, and higher efficiency. However, most existing workflow management systems enforce rigid inflexible workflows and rely on direct manual input. Both are inadequate for healthcare processes. In particular, direct manual input is not possible in most cases since (1) it would distract the personnel even in critical situations and (2) it would violate fundamental hygiene principles by requiring disinfected doctors and nurses to touch input devices. The solution could be activity recognition systems that use sensor data (e.g., audio and acceleration data) to infer the current activities by the personnel and provide input to a workflow (e.g., informing it that a certain activity is finished now). However, state-of-the-art activity recognition technologies have difficulties in providing reliable information. We describe a comprehensive framework tailored for flexible human-centric healthcare processes that improves the reliability of activity recognition data. We present a set of mechanisms that exploit the application knowledge encoded in workflows in order to reduce the uncertainty of this data, thus enabling unobtrusive robust healthcare workflows. We evaluate our work based on a real-world case study and show that the robustness of unobtrusive healthcare workflows can be increased to an absolute value of up to 91\% (compared to only 12\% with a classical workflow system). This is a major breakthrough that paves the way towards future IT-enabled healthcare systems.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2013-13&engl=1}
}
@article {ART-2013-04,
   author = {Anders Gidenstam and Boris Koldehofe and Marina Papatriantafilou and Philippas Tsigas},
   title = {{Scalable group communication supporting configurable levels of consistency}},
   journal = {Concurrency and Computation: Practice and Experience},
   publisher = {John Wiley \& Sons, Ltd.},
   volume = {25},
   number = {5},
   pages = {649--671},
   type = {Article in Journal},
   month = {January},
   year = {2013},
   doi = {10.1002/cpe.1801},
   keywords = {Distributed Systems, Group Communication, Consistency},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Group communication is deployed in many evolving Internet-scale cooperative applications such as multiplayer online games and virtual worlds to efficiently support interaction on information relevant to a potentially very large number of users or objects. Especially peer-to-peer based group communication protocols have evolved as a promising approach to allow intercommunication between many distributed peers. Yet, the delivery semantics of robust and scalable protocols such as gossiping is not sufficient to support consistency semantics beyond eventual consistency because no relationship on the order of events is enforced. On the other hand, traditional consistency models provided by reliable group communication providing causal or even total order are restricted to support only small groups. This article proposes the cluster consistency model which bridges the gap between traditional and current approaches in supporting both scalability and ordered event delivery. We introduce a dynamic and fault tolerant cluster management method that can coordinate concurrent access to resources in a peer-to-peer system and can be used to establish fault-tolerant configurable cluster consistency with predictable reliability, running on top of decentralised probabilistic protocols supporting scalable group communication. This is achieved by a general two-layered architecture that can be applied on top of the standard Internet communication layers and offers a modular, layered set of services to the applications that need them. Further, we present a fault-tolerant method implementing causal cluster consistency with predictable reliability, running on top of decentralised probabilistic protocols supporting group communication. This paper provides analytical and experimental evaluation of the properties regarding the fault tolerance of the approach. Furthermore, our experimental study, conducted by implementing and evaluating the two-layered architecture on top of standard Internet transport services, shows that the approach scales well, imposes an even load on the system, and provides high-probability reliability guarantees.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2013-04&engl=1}
}
@article {ART-2013-02,
   author = {Marius Wernke and Frank D{\"u}rr and Kurt Rothermel},
   title = {{PShare: Ensuring location privacy in non-trusted systems through multi-secret sharing}},
   journal = {Pervasive and Mobile Computing},
   publisher = {Elsevier},
   pages = {1--17},
   type = {Article in Journal},
   month = {February},
   year = {2013},
   doi = {10.1016/j.pmcj.2013.01.001},
   keywords = {Location-based applications; Privacy; Position sharing; Location management},
   language = {English},
   cr-category = {C.2.4 Distributed Systems},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2013-02/ART-2013-02.pdf,     http://www.priloc.de,     http://dx.doi.org/10.1016/j.pmcj.2013.01.001},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Location-based applications such as Facebook Places, Foursquare, or Loopt typically use location services to manage mobile object positions. However, exposing precise user positions raises user privacy concerns, especially if location service providers are not fully trusted. To enable the secure management of private user positions in non-trusted systems, we present two novel position sharing approaches based on the concept of multi-secret sharing. We improve existing geometric position sharing approaches [1, 2] by considering continuous position updates and by increasing the robustness against various attacks. Furthermore, we present the first position sharing approach for symbolic location models.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2013-02&engl=1}
}
@article {ART-2013-01,
   author = {Stephan Schuhmann and Klaus Herrmann and Kurt Rothermel and Yazan Boshmaf},
   title = {{Adaptive Composition of Distributed Pervasive Applications in Heterogeneous Environments}},
   journal = {ACM Transactions on Autonomous and Adaptive Systems},
   publisher = {ACM},
   volume = {8},
   number = {2},
   pages = {1--21},
   type = {Article in Journal},
   month = {July},
   year = {2013},
   doi = {10.1145/2491465.2491469},
   issn = {1556-4665},
   keywords = {Adaptivity; Algorithms; Automation; Components; Design; Heterogeneity; Hybrid Configuration; Management; Measurement; Middleware; Partial Configurations; Pervasive Applications; Service Composition},
   language = {English},
   cr-category = {C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2013-01/ART-2013-01.pdf,     http://doi.acm.org/10.1145/2491465.2491469},
   department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems},
   abstract = {Complex pervasive applications need to be distributed for two main reasons: due to the typical resource restrictions of mobile devices, and to use local services to interact with the immediate environment. To set up such an application, the distributed components require spontaneous composition. Since dynamics in the environment and device failures may imply the unavailability of components and devices at any time, finding, maintaining, and adapting such a composition is a nontrivial task. Moreover, the speed of such a configuration process directly influences the user since in the event of a configuration, the user has to wait. In this article, we introduce configuration algorithms for homogeneous and heterogeneous environments. We discuss a comprehensive approach to pervasive application configuration that adapts to the characteristics of the environment: It chooses the most efficient configuration method for the given environment to minimize the configuration latency. Moreover, we propose a new scheme for caching and reusing partial application configurations. This scheme reduces the configuration latency even further such that a configuration can be executed without noticeable disturbance of the user.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2013-01&engl=1}
}