@inproceedings {INPROC-2018-55, author = {Guilherme F. Lima and Ahmad Slo and Sukanya Bhowmik and Markus Endler and Kurt Rothermel}, title = {{Skipping Unused Events to Speed Up Rollback-Recovery in Distributed Data-Parallel CEP}}, booktitle = {Proceedings of 2018 IEEE/ACM 5th International Conference on Big Data Computing Applications and Technologies (BDCAT)}, publisher = {IEEE}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--10}, type = {Conference Paper}, month = {December}, year = {2018}, language = {English}, cr-category = {C.2.4 Distributed Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-55/INPROC-2018-55.pdf}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {We propose two extensions for a state-of-the-art method of rollback-recovery in distributed CEP (complex event processing). In CEP, an operator network is used to search for patterns in events streams. Sometimes these operators fail and lose their state. Rollback-recovery is a method for dealing with such state losses. The type of rollback-recovery we consider is upstream backup, where the state of a failed operator is recovered by replaying to it the input events that led it to that state. These events are kept in upstream operators{\^a}€™ memory buffers, which are trimmed continuously as the downstream operator progresses. The first extension we propose saves memory and speeds up recovery by avoiding to store and retransmit unnecessary events. The second extension makes the base method of upstream backup compatible with data-parallel CEP, allowing that the windows into which operators partition their input be processed in parallel. We evaluated the proposed extensions through experiments that showed a significant reduction in memory usage and recovery time at the expense of a negligible processing overhead during normal operation.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-55&engl=1} } @inproceedings {INPROC-2018-46, author = {Jonathan Falk and Frank D{\"u}rr and Kurt Rothermel}, title = {{Exploring Practical Limitations of Joint Routing and Scheduling for TSN with ILP}}, booktitle = {Proceedings of the 2018 IEEE 24th International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA 2018) Hakodate, Japan, 29-31 August 2018}, publisher = {IEEE}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {136--146}, type = {Conference Paper}, month = {August}, year = {2018}, doi = {10.1109/RTCSA.2018.00025}, language = {English}, cr-category = {C.2.4 Distributed Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-46/INPROC-2018-46.pdf, https://ieeexplore.ieee.org/document/8607243}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {IEEE 802.1Q networks with extensions for time-sensitive networking aim to enable converged networks. Converged networks support hard-real time communication services in addition to the currently supported services classes. Real-time communication in these networks requires routes and schedules for the real-time transmissions. We present a formulation in the integer linear programming (ILP) framework which models the joint routing and scheduling problem for flows of periodic real-time transmissions in converged TSN networks. In the joint routing and scheduling problem, both routes and schedules for real-time transmissions are computed in one step, i.e. we do not schedule over predefined routes. We explore the practical limitations of this approach by evaluating the runtime of problem instances with widely varying parameters with a state-of-the-art ILP solver. The observed solver runtimes indicate the qualitative impact of the number of real-time flows, the size of the network, the transmission frequency of real-time transmissions, and the network topology.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-46&engl=1} } @inproceedings {INPROC-2018-45, author = {Christian Mayer and Ruben Mayer and Sukanya Bhowmik and Lukas Epple and Kurt Rothermel}, title = {{HYPE: Massive Hypergraph Partitioning with Neighborhood Expansion}}, booktitle = {Proceedings of the 2018 IEEE International Conference on Big Data (BigData '18); Seattle, WA, USA, December 10-13, 2018}, publisher = {IEEE}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--10}, type = {Conference Paper}, month = {December}, year = {2018}, language = {English}, cr-category = {C.2.4 Distributed Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-45/INPROC-2018-45.pdf}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {Many important real-world applications---such as social networks or distributed data bases---can be modeled as hypergraphs. In such a model, vertices represent entities---such as users or data records---whereas hyperedges model a group membership of the vertices---such as the authorship in a specific topic or the membership of a data record in a specific replicated shard. To optimize such applications, we need an efficient and effective solution to the NP-hard balanced k-way hypergraph partitioning problem. However, existing hypergraph partitioners that scale to very large graphs do not effectively exploit the hypergraph structure when performing the partitioning decisions. We propose HYPE, a hypergraph partitionier that exploits the neighborhood relations between vertices in the hypergraph using an efficient implementation of neighborhood expansion. HYPE improves partitioning quality by up to 95\% and reduces runtime by up to 39\% compared to the state of the art.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-45&engl=1} } @inproceedings {INPROC-2018-30, author = {Johannes K{\"a}ssinger and Mohamed Abdelaal and Fank D{\"u}rr and Kurt Rothermel}, title = {{GreenMap: Approximated Filtering towards Energy-Aware Crowdsensing for Indoor Mapping}}, booktitle = {Proceedings of the 2018 IEEE 15th International Conference on Mobile Ad-hoc and Sensor Systems (MASS2018)}, address = {Chengdu, China}, publisher = {IEEE}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {451--459}, type = {Conference Paper}, month = {October}, year = {2018}, doi = {10.1109/MASS.2018.00069}, keywords = {Crowdsensing; Mobile Sensing; Indoor; Pointcloud; Approximate Computing; Approximate Filtering}, language = {English}, cr-category = {C.2.4 Distributed Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-30/INPROC-2018-30.pdf}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {Recently, mobile crowdsensing has become an appealing paradigm thanks to the ubiquitous presence of powerful mobile devices. Indoor mapping, as an example of crowdsensingdriven applications, is essential to provide many indoor locationbased services, such as emergency response, security, and tracking/navigation in large buildings. In this realm, 3D point clouds stand as an optimal data type which can be crowdsensed—using currently-available mobile devices, e.g. Google Tango, Microsoft Hololens and Apple ARKit—to generate floor plans with different levels of detail, i.e. 2D and 3D mapping. However, collecting such bulky data from ”resources-limited“ mobile devices can significantly harm their energy efficiency. To overcome this challenge, we introduce GreenMap, an energy-aware architectural framework for automatically mapping the interior spaces using crowdsensed point clouds with the support of structural information encoded in formal grammars. GreenMap reduces the energy overhead through projecting the point clouds to several filtration steps on the mobile devices. In this context, GreenMap leverages the potential of approximate computing to reduce the computational cost of data filtering while maintaining a satisfactory level of modeling accuracy. To this end, we propose two approximation strategies, namely DyPR and SuFFUSION. To demonstrate the effectiveness of GreenMap, we implemented a crowdsensing Android App to collect 3D point clouds from two different buildings. We show that GreenMap achieves significant energy savings of up to 67.8\%, compared to the baseline methods, while generating comparable floor plans.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-30&engl=1} } @inproceedings {INPROC-2018-29, author = {Mohamed Abdelaal and Daniel Reichelt and Frank Duerr and Kurt Rothermel and Lavinia Runceanu and Susanne Becker and Fritsch Dieter}, title = {{ComNSense: Grammar-Driven Crowd-Sourcing of Point Clouds for Automatic Indoor Mapping}}, booktitle = {Proceedings of the 2018 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp 2018), PACM IMWUT Issue 1, October 2018.}, address = {Singapore}, publisher = {ACM}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--26}, type = {Conference Paper}, month = {October}, year = {2018}, keywords = {Indoor Mapping; Crowdsensing; 3D Point Clouds; Energy Efficiency; Formal Grammars}, language = {English}, cr-category = {C.3 Special-Purpose and Application-Based Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-29/INPROC-2018-29.pdf}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-29&engl=1} } @inproceedings {INPROC-2018-26, author = {Zohaib Riaz and Frank D{\"u}rr and Kurt Rothermel}, title = {{Location Privacy and Utility in Geo-social: Survey and Research Challenges}}, booktitle = {Proceedings of the 16th Annual Conference on Privacy, Security and Trust (PST 2018), August 28-30, 2018, Belfast, Northern Ireland, United Kingdom.}, publisher = {IEEE Xplore}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--10}, type = {Conference Paper}, month = {August}, year = {2018}, language = {English}, cr-category = {K.4 Computers and Society}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-26/INPROC-2018-26.pdf}, contact = {zohaib.riaz@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-26&engl=1} } @inproceedings {INPROC-2018-21, author = {Saravana Murthy Palanisamy and Frank D{\"u}rr and Muhammad Adnan Tariq and Kurt Rothermel}, title = {{Preserving Privacy and Quality of Service in Complex Event Processing through Event Reordering}}, booktitle = {Conference Proceedings: Proceedings of the 12th ACM International Conference on Distributed and Event-Based Systems: DEBS2018 ; Hamilton, New Zealand, June 25-29, 2018}, address = {Hamilton, New Zealand}, publisher = {ACM}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, series = {Saravana Murthy Palanisamy}, pages = {40--51}, type = {Conference Paper}, month = {June}, year = {2018}, isbn = {978-1-4503-5782-1}, language = {English}, cr-category = {D.4.6 Operating Systems Security and Protection, G.1.6 Numerical Analysis Optimization, F.1.1 Models of Computation}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-21/INPROC-2018-21.pdf, https://doi.org/10.1145/3210284.3210296}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-21&engl=1} } @inproceedings {INPROC-2018-16, author = {Thomas Kohler and Ruben Mayer and Frank D{\"u}rr and Marius Maa{\ss} and Sukanya Bhowmik and Kurt Rothermel}, title = {{P4CEP: Towards In-Network Complex Event Processing}}, booktitle = {Proceedings of the ACM SIGCOMM 2018 Morning Workshop on In-Network Computing}, address = {Budapest, Hungary}, publisher = {ACM}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, series = {NetCompute'18}, pages = {0--5}, type = {Conference Paper}, month = {August}, year = {2018}, doi = {10.1145/3229591.3229593}, isbn = {978-1-4503-5908-5/18/08}, keywords = {In-network Computing, Data Plane Programming, P4, Complex Event Processing (CEP)}, language = {English}, cr-category = {C.2.1 Network Architecture and Design, C.2.4 Distributed Systems, C.2.3 Network Operations}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2018-16/INPROC-2018-16.pdf, https://doi.org/10.1145/3229591.3229593}, contact = {thomas.kohler@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {In-network computing using programmable networking hardware is a strong trend in networking that promises to reduce latency and consumption of server resources through offloading to network elements (programmable switches and smart NICs). In particular, the data plane programming language P4 together with powerful P4 networking hardware has spawned projects offloading services into the network, e.g., consensus services or caching services. In this paper, we present a novel case for in-network computing, namely, Complex Event Processing (CEP). CEP processes streams of basic events, e.g., stemming from networked sensors, into meaningful complex events. Traditionally, CEP processing has been performed on servers or overlay networks. However, we argue in this paper that CEP is a good candidate for in-network computing along the communication path avoiding detouring streams to distant servers to minimize communication latency while also exploiting processing capabilities of novel networking hardware. We show that it is feasible to express CEP operations in P4 and also present a tool to compile CEP operations, formulated in our P4CEP rule specification language, to P4 code. Moreover, we identify challenges and problems that we have encountered to show future research directions for implementing full-fledged in-network CEP systems.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-16&engl=1} } @inproceedings {INPROC-2018-15, author = {Christoph Stach and Sascha Alpers and Stefanie Betz and Frank D{\"u}rr and Andreas Fritsch and Kai Mindermann and Saravana Murthy Palanisamy and Gunther Schiefer and Manuela Wagner and Bernhard Mitschang and Andreas Oberweis and Stefan Wagner}, title = {{The AVARE PATRON: A Holistic Privacy Approach for the Internet of Things}}, booktitle = {Proceedings of the 15th International Conference on Security and Cryptography (SECRYPT '18)}, publisher = {INSTICC Press}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--8}, type = {Conference Paper}, month = {July}, year = {2018}, keywords = {Privacy; IoT Apps; Smart Things; Stream Processing; Privacy Preferences Elicitation \& Veri\&\#64257; cation}, language = {English}, cr-category = {K.4.1 Computers and Society Public Policy Issues, D.4.6 Operating Systems Security and Protection}, contact = {Senden Sie eine E-Mail an Christoph.Stach@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems; University of Stuttgart, Institute of Software Technology, Software Engineering; University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {Applications for the Internet of Things are becoming increasingly popular. Due to the large amount of available context data, such applications can be used effectively in many domains. By interlinking these data and analyzing them, it is possible to gather a lot of knowledge about a user. Therefore, these applications pose a threat to privacy. In this paper, we illustrate this threat by looking at a real-world application scenario. Current state of the art focuses on privacy mechanisms either for Smart Things or for big data processing systems. However, our studies show that for a comprehensive privacy protection a holistic view on these applications is required. Therefore, we describe how to combine two promising privacy approaches from both categories, namely AVARE and PATRON. Evaluation results confirm the thereby achieved synergy effects.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-15&engl=1} } @inproceedings {INPROC-2018-04, author = {Christoph Stach and Frank D{\"u}rr and Kai Mindermann and Saravana Murthy Palanisamy and Stefan Wagner}, title = {{How a Pattern-based Privacy System Contributes to Improve Context Recognition}}, booktitle = {Proceedings of the 2018 IEEE International Conference on Pervasive Computing and Communications Workshops (CoMoRea)}, publisher = {IEEE Computer Society}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--6}, type = {Workshop Paper}, month = {March}, year = {2018}, keywords = {privacy; access control; pattern concealing; stream processing; complex event processing; databases}, language = {English}, cr-category = {K.4.1 Computers and Society Public Policy Issues, D.4.6 Operating Systems Security and Protection}, contact = {Senden Sie eine E-Mail an Christoph.Stach@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems; University of Stuttgart, Institute of Software Technology, Software Engineering; University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {As Smart Devices have access to a lot of user-preferential data, they come in handy in any situation. Although such data - as well as the knowledge which can be derived from it - is highly beneficial as apps are able to adapt their services appropriate to the respective context, it also poses a privacy threat. Thus, a lot of research work is done regarding privacy. Yet, all approaches obfuscate certain attributes which has a negative impact on context recognition and thus service quality. Therefore, we introduce a novel access control mechanism called PATRON. The basic idea is to control access to information patterns. For instance, a person suffering from diabetes might not want to reveal his or her unhealthy eating habit, which can be derived from the pattern ``rising blood sugar level'' -$>$ ``adding bread units''. Such a pattern which must not be discoverable by some parties (e.g., insurance companies) is called private pattern whereas a pattern which improves an app's service quality is labeled as public pattern. PATRON employs different techniques to conceal private patterns and, in case of available alternatives, selects the one with the least negative impact on service quality, such that the recognition of public patterns is supported as good as possible.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2018-04&engl=1} } @article {ART-2018-10, author = {Thomas Kohler and Frank D{\"u}rr and Kurt Rothermel}, title = {{ZeroSDN: A Highly Flexible and Modular Architecture for Full-range Distribution of Event-based Network Control}}, journal = {IEEE Transactions on Network and Service Management}, editor = {Wolfgang Kellerer}, publisher = {IEEE Communications Society}, pages = {1--14}, type = {Article in Journal}, month = {January}, year = {2018}, keywords = {Software-defined Networking; OpenFlow; Control Plane Distribution; Publish/Subscribe; White-box Networking; Virtualization}, language = {English}, cr-category = {C.2.1 Network Architecture and Design, C.2.4 Distributed Systems, C.2.3 Network Operations}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2018-10/ART-2018-10.pdf}, contact = {thomas.kohler@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2018-10&engl=1} } @article {ART-2018-09, author = {Sukanya Bhowmik and Muhammad Adnan Tariq and Jonas Grunert and Deepak Srinivasan and Kurt Rothermel}, title = {{Expressive Content-Based Routing in Software-Defined Networks}}, journal = {IEEE Transactions on Parallel and Distributed Systems}, publisher = {IEEE}, pages = {1--18}, type = {Article in Journal}, month = {May}, year = {2018}, 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/ART-2018-09/ART-2018-09.pdf}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2018-09&engl=1} } @article {ART-2018-01, author = {Christoph Dibak and Bernard Haasdonk and Andreas Schmidt and Frank D{\"u}rr and Kurt Rothermel}, title = {{Enabling Interactive Mobile Simulations Through Distributed Reduced Models}}, journal = {Pervasive and Mobile Computing}, publisher = {Elsevier BV}, pages = {1--26}, type = {Article in Journal}, month = {February}, year = {2018}, doi = {10.1016/j.pmcj.2018.02.002}, language = {English}, cr-category = {C.2.4 Distributed Systems}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems}, abstract = {}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2018-01&engl=1} }