Florian Dorfmeister, Dipl-Medieninf.

Florian Dorfmeister, Dipl.-Medieninf.

Lehrstuhl für Mobile und Verteilte Systeme

Ludwig-Maximilians-Universität München, Institut für Informatik

Raum

Telefon:

Fax:

Mail: florian.dorfmeister@ifi.lmu.de

Publikationen

2016

  • A. Ebert, S. Feld, and F. Dorfmeister, "Segmented and Directional Impact Detection for Parked Vehicles using Mobile Devices," in 23rd International Conference on Systems, Signals and Image Processing (IWSSIP 2016), 2016.
    [BibTeX]
    @InProceedings{ebert2016segmented,
    Title = {Segmented and Directional Impact Detection for Parked Vehicles using Mobile Devices},
    Author = {André Ebert and Sebastian Feld and Florian Dorfmeister},
    Booktitle = {23rd International Conference on Systems, Signals and Image Processing (IWSSIP 2016)},
    Year = {2016},
    Publisher = {IEEE},
    Owner = {aebert},
    Timestamp = {2016.07.01}
    }
  • L. Schauer, F. Dorfmeister, and F. Wirth, "Analyzing Passive Wi-Fi Fingerprinting for Privacy-Preserving Indoor-Positioning," in 6th International Conference on Localization and GNSS (ICL-GNSS 2016), 2016.
    [BibTeX] [Download PDF]
    @InProceedings{schauer2016analyzing,
    Title = {Analyzing Passive Wi-Fi Fingerprinting for Privacy-Preserving Indoor-Positioning},
    Author = {Lorenz Schauer and Florian Dorfmeister and Florian Wirth},
    Booktitle = {6th International Conference on Localization and GNSS (ICL-GNSS 2016)},
    Year = {2016},
    Owner = {lschauer},
    Timestamp = {2016.07.28},
    Url = {http://www.cip.ifi.lmu.de/~schauer/publications/schauer2016analyzing.pdf}
    }

2015

  • F. Dorfmeister, K. Wiesner, M. Schuster, and M. Maier, "Preventing Restricted Space Inference in Online Route Planning Services," in 12th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2015), 2015.
    [BibTeX]
    @InProceedings{dorfmeister2015prospr,
    Title = {Preventing Restricted Space Inference in Online Route Planning Services},
    Author = {Florian Dorfmeister and Kevin Wiesner and Michael Schuster and Marco Maier},
    Booktitle = {12th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2015)},
    Year = {2015},
    Owner = {fdorfmeister},
    Timestamp = {2015.07.10}
    }
  • A. Ebert, F. Dorfmeister, M. Maier, and C. Linnhoff-Popien, "Context-, Resource-, and User-Aware Provision of Services on Mobile Devices," International Journal On Advances in Networks and Services, vol. 8, iss. 1&2, pp. 81-91, 2015.
    [BibTeX]
    @Article{crua15,
    Title = {Context-, Resource-, and User-Aware Provision of Services on Mobile Devices},
    Author = {André Ebert and Florian Dorfmeister and Marco Maier and Claudia Linnhoff-Popien},
    Journal = {International Journal On Advances in Networks and Services},
    Year = {2015},
    Number = {1\&2},
    Pages = {81 -91},
    Volume = {8},
    Owner = {aebert},
    Timestamp = {2015.07.17}
    }
  • A. Ebert, F. Dorfmeister, M. Maier, and C. Linnhoff-Popien, "EMMA: A Context-Aware Middleware For Energy Management on Mobile Devices," in 7th International Conference on Advances in Human-oriented and Personalized Mechanisms, Technologies, and Services (SoftNet 2014), 2015.
    [BibTeX]
    @InProceedings{emma14,
    Title = {EMMA: A Context-Aware Middleware For Energy Management on Mobile Devices},
    Author = {André Ebert and Florian Dorfmeister and Marco Maier and Claudia Linnhoff-Popien},
    Booktitle = {7th International Conference on Advances in Human-oriented and Personalized Mechanisms, Technologies, and Services (SoftNet 2014)},
    Year = {2015},
    Publisher = {IARIA},
    Owner = {aebert},
    Timestamp = {2015.07.17}
    }
  • M. Maier, L. Schauer, and F. Dorfmeister, "ProbeTags: Privacy-Preserving Proximity Detection Using Wi-Fi Management Frames," in 11th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WIMOB 2015), 2015.
    [BibTeX]
    @InProceedings{maier15probetags,
    Title = {ProbeTags: Privacy-Preserving Proximity Detection Using Wi-Fi Management Frames},
    Author = {Marco Maier and Lorenz Schauer and Florian Dorfmeister},
    Booktitle = {11th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WIMOB 2015)},
    Year = {2015},
    Owner = {mmaier},
    Timestamp = {2015.11.13}
    }
  • M. Werner, F. Dorfmeister, and M. Schönfeld, "AMBIENCE: A Context-Centric Online Social Network," in Accepted for Inclusion in the 12th Workshop on Positioning, Navigation and Communications (WPNC 2015), 2015.
    [BibTeX] [Download PDF]
    @InProceedings{ambience,
    Title = {AMBIENCE: A Context-Centric Online Social Network},
    Author = {Martin Werner and Florian Dorfmeister and Mirco Schönfeld},
    Booktitle = {Accepted for Inclusion in the 12th Workshop on Positioning, Navigation and Communications (WPNC 2015)},
    Year = {2015},
    Publisher = {IEEE},
    File = {2015-Ambience.pdf:http\://publications.mircoschoenfeld.de/2015-Ambience.pdf:PDF},
    Url = {http://publications.mircoschoenfeld.de/2015-Ambience.pdf}
    }

2014

  • F. Dorfmeister, S. Feld, and C. Linnhoff-Popien, "ALPACA: A Decentralized, Privacy-Centric and Context-Aware Framework for the Dissemination of Context Information," International Journal On Advances in Intelligent Systems, vol. 7, iss. 1 and 2, pp. 223-236, 2014.
    [BibTeX] [Abstract]
    With the ongoing rise of smartphones as everyday mobile devices and their steadily increasing amount of sensing and communication capabilities, we are on the brink of a subtle, widespread adoption of context-aware computing techniques into our daily lives. Focusing on functionality and performance, the majority of existing architectures for managing context information typically deploy central components for collecting, analyzing and distributing its users' up-to-date data. However, preservation of users' privacy needs remains a crucial factor for such systems' acceptableness. Inspired by existing works on privacy in context-aware applications and the authors' beliefs in the necessity to put users back in control, this article adopts a privacy-centric perspective and presents ALPACA: A novel approach for modeling and managing a user's rich context information in a user-centric and privacy-preserving way fit for a multitude of different usage scenarios. To this end, this article offers a general conceptual mapping of a user's privacy needs to distinct layers. Based on this conceptualization we introduce a privacy-centric approach for modeling this information. Additionally, we propose a context-aware mechanism for the definition of context-dependent release triggers in order to enable fine-grained control over the disclosure of sensitive information. Finally, we present the components of the proposed system architecture, explain how they interact with each other and discuss how our framework can be integrated into a modern mobile operating system.
    @Article{dorfmeister2014alpaca,
    Title = {ALPACA: A Decentralized, Privacy-Centric and Context-Aware Framework for the Dissemination of Context Information},
    Author = {Florian Dorfmeister and Sebastian Feld and Claudia Linnhoff-Popien},
    Journal = {International Journal On Advances in Intelligent Systems},
    Year = {2014},
    Number = {1 and 2},
    Pages = {223-236},
    Volume = {7},
    Abstract = {With the ongoing rise of smartphones as everyday mobile devices and their steadily increasing amount of sensing and communication capabilities, we are on the brink of a subtle, widespread adoption of context-aware computing techniques into our daily lives. Focusing on functionality and performance, the majority of existing architectures for managing context information typically deploy central components for collecting, analyzing and distributing its users' up-to-date data. However, preservation of users' privacy needs remains a crucial factor for such systems' acceptableness. Inspired by existing works on privacy in context-aware applications and the authors' beliefs in the necessity to put users back in control, this article adopts a privacy-centric perspective and presents ALPACA: A novel approach for modeling and managing a user's rich context information in a user-centric and privacy-preserving way fit for a multitude of different usage scenarios. To this end, this article offers a general conceptual mapping of a user's privacy needs to distinct layers. Based on this conceptualization we introduce a privacy-centric approach for modeling this information. Additionally, we propose a context-aware mechanism for the definition of context-dependent release triggers in order to enable fine-grained control over the disclosure of sensitive information. Finally, we present the components of the proposed system architecture, explain how they interact with each other and discuss how our framework can be integrated into a modern mobile operating system.},
    Owner = {fdorfmeister}
    }
  • M. Maier, C. Marouane, M. Klette, F. Dorfmeister, P. Marcus, and C. Linnhhoff-Popien, "SURFtogether: Towards Context Proximity Detection Using Visual Features," in 3rd International Conference on Context-Aware Systems and Applications (ICCASA 2014), 2014, pp. 86-91.
    [BibTeX]
    @InProceedings{maier2014surftogether,
    Title = {SURFtogether: Towards Context Proximity Detection Using Visual Features},
    Author = {Marco Maier and Chadly Marouane and Manuel Klette and Florian Dorfmeister and Philipp Marcus and Claudia Linnhhoff-Popien},
    Booktitle = {3rd International Conference on Context-Aware Systems and Applications (ICCASA 2014)},
    Year = {2014},
    Pages = {86-91},
    Owner = {mmaier},
    Timestamp = {2015.07.10}
    }
  • K. Wiesner, F. Dorfmeister, and C. Linnhhoff-Popien, "PRICAPS: A System for Privacy-Preserving Calibration in Participatory Sensing Networks," EAI Endorsed Transactions on Ubiquitous Environments, vol. 3, pp. 1-11, 2014.
    [BibTeX]
    @Article{wiesner14pricaps,
    Title = {PRICAPS: A System for Privacy-Preserving Calibration in Participatory Sensing Networks},
    Author = {Kevin Wiesner and Florian Dorfmeister and Claudia Linnhhoff-Popien},
    Journal = {EAI Endorsed Transactions on Ubiquitous Environments},
    Year = {2014},
    Pages = {1-11},
    Volume = {3},
    Owner = {kwiesner},
    Timestamp = {2015.07.10}
    }
  • K. Wiesner, S. Feld, F. Dorfmeister, and C. Linnhoff-Popien, "Right to Silence: Establishing Map-based Silent Zones for Participatory Sensing," in IEEE 9th International Conference on Intelligent Sensors, Sensor Networks and Information Processing (IEEE ISSNIP 2014), 2014, pp. 339-344.
    [BibTeX] [Abstract]
    Participatory sensing tries to create cost-effective, large-scale sensing systems by leveraging sensors embedded in mobile devices. One major challenge in these systems is to protect the users' privacy, since users will not contribute data if their privacy is jeopardized. Especially location data needs to be protected if it is likely to reveal information about the users' identities. A common solution is the blinding out approach that creates so-called ban zones in which location data is not published. Thereby, a user's important places, e.g., her home or workplace, can be concealed. However, ban zones of a fixed size are not able to guarantee any particular level of privacy. For instance, a ban zone that is large enough to conceal a user's home in a large city might be too small in a less populated area. For this reason, we propose an approach for dynamic map-based blinding out: The boundaries of our privacy zones, called Silent Zones, are determined in such way that at least k buildings are located within this zone. Thus, our approach adapts to the habitat density and we can guarantee k-anonymity in terms of surrounding buildings. In this paper, we present two new algorithms for creating Silent Zones and evaluate their performance. Our results show that especially in worst case scenarios, i.e., in sparsely populated areas, our approach outperforms standard ban zones and guarantees the specified privacy level.
    @InProceedings{silentzones,
    Title = {Right to Silence: Establishing Map-based Silent Zones for Participatory Sensing},
    Author = {Kevin Wiesner and Sebastian Feld and Florian Dorfmeister and Claudia Linnhoff-Popien},
    Booktitle = {IEEE 9th International Conference on Intelligent Sensors, Sensor Networks and Information Processing (IEEE ISSNIP 2014)},
    Year = {2014},
    Pages = {339-344},
    Abstract = {Participatory sensing tries to create cost-effective, large-scale sensing systems by leveraging sensors embedded in mobile devices. One major challenge in these systems is to protect the users' privacy, since users will not contribute data if their privacy is jeopardized. Especially location data needs to be protected if it is likely to reveal information about the users' identities. A common solution is the blinding out approach that creates so-called ban zones in which location data is not published. Thereby, a user's important places, e.g., her home or workplace, can be concealed. However, ban zones of a fixed size are not able to guarantee any particular level of privacy. For instance, a ban zone that is large enough to conceal a user's home in a large city might be too small in a less populated area. For this reason, we propose an approach for dynamic map-based blinding out: The boundaries of our privacy zones, called Silent Zones, are determined in such way that at least k buildings are located within this zone. Thus, our approach adapts to the habitat density and we can guarantee k-anonymity in terms of surrounding buildings. In this paper, we present two new algorithms for creating Silent Zones and evaluate their performance. Our results show that especially in worst case scenarios, i.e., in sparsely populated areas, our approach outperforms standard ban zones and guarantees the specified privacy level.},
    Owner = {kwiesner}
    }

2013

  • F. Dorfmeister, S. Feld, C. Linnhoff-Popien, and S. A. W. Verclas, "Privacy-Centric Modeling and Management of Context Information," in 6th International Conference on Advances in Human oriented and Personalized Mechanisms, Technologies, and Services (CENTRIC 2013), 2013, pp. 92-97.
    [BibTeX] [Abstract]
    Context-aware computing has been an intensively researched topic for years already. Consequently, there exists a plethora of usage scenarios for context-aware applications as well as several approaches for the modeling and management of a user's context information, many of which focus on the efficient and scalable distribution of the latter. With the ongoing rise of smartphones as everyday mobile devices and their steadily increasing amount of sensing and communication capabilities, we finally find ourselves at the edge towards a widespread usage of these techniques. However, apart from technical issues such as how to reliably determine a user’s current context, privacy still remains a crucial factor for these systems’ acceptance rate. Therefore, inspired by earlier works on privacy in context-aware computing and the authors’ beliefs in the necessity to put users in control, this paper presents a novel approach for modeling and managing a mobile user’s context information in a user-centric and privacy-preserving way. To this end, this work’s contribution is twofold: First, based on widely recognized requirements for privacy in context-aware applications, we propose a privacy-centric context model which allows for an intuitive and context-dependent definition of a user’s privacy preferences, directly integrating privacy aspects into the context model itself. Second, we present a generic and flexible architecture for the management and distribution of context information in a privacy-preserving way fit for a multitude of different usage scenarios.
    @InProceedings{dorfmeister2013privacy,
    Title = {Privacy-Centric Modeling and Management of Context Information},
    Author = {Florian Dorfmeister and Sebastian Feld and Claudia Linnhoff-Popien and Stephan A. W. Verclas},
    Booktitle = {6th International Conference on Advances in Human oriented and Personalized Mechanisms, Technologies, and Services (CENTRIC 2013)},
    Year = {2013},
    Pages = {92-97},
    Abstract = {Context-aware computing has been an intensively researched topic for years already. Consequently, there exists a plethora of usage scenarios for context-aware applications as well as several approaches for the modeling and management of a user's context information, many of which focus on the efficient and scalable distribution of the latter. With the ongoing rise of smartphones as everyday mobile devices and their steadily increasing amount of sensing and communication capabilities, we finally find ourselves at the edge towards a widespread usage of these techniques. However, apart from technical issues such as how to reliably determine a user’s current context, privacy still remains a crucial factor for these systems’ acceptance rate. Therefore, inspired by earlier works on privacy in context-aware computing and the authors’ beliefs in the necessity to put users in control, this paper presents a novel approach for modeling and managing a mobile user’s context information in a user-centric and privacy-preserving way. To this end, this work’s contribution is twofold: First, based on widely recognized requirements for privacy in context-aware applications, we propose a privacy-centric context model which allows for an intuitive and context-dependent definition of a user’s privacy preferences, directly integrating privacy aspects into the context model itself. Second, we present a generic and flexible architecture for the management and distribution of context information in a privacy-preserving way fit for a multitude of different usage scenarios.},
    Owner = {fdorfmeister}
    }
  • M. Maier and F. Dorfmeister, "Fine-Grained Activity Recognition of Pedestrians Travelling by Subway," in 5th International Conference on Mobile Computing, Applications and Services (MobiCASE 2013), 2013. doi:10.1007/978-3-319-05452-0_10
    [BibTeX] [Abstract] [Download PDF]
    With the now widespread usage of increasingly powerful smartphones, pro-active, context-aware, and thereby unobstrusive applications have become possible. A user’s current activity is a primary piece of contextual information, and especially in urban areas, a user’s current mode of transport is an important part of her activity. A lot of research has been conducted on automatically recognizing different means of transport, but up to now, no attempt has been made to perform a fine-grained classification of different activities related to travelling by local public transport. In this work, we present an approach to recognize 17 different activities related to travelling by subway. We use only the sensor technology available in modern mobile phones and achieve a high classification accuracy of over 90%, without requiring a specific carrying position of the device. We discuss the usefulness of different sensors and computed features, and identify individual characteristics of the considered activities.
    @InProceedings{subway,
    Title = {Fine-Grained Activity Recognition of Pedestrians Travelling by Subway},
    Author = {Marco Maier and Florian Dorfmeister},
    Booktitle = {5th International Conference on Mobile Computing, Applications and Services (MobiCASE 2013)},
    Year = {2013},
    Abstract = {With the now widespread usage of increasingly powerful smartphones, pro-active, context-aware, and thereby unobstrusive applications have become possible. A user’s current activity is a primary piece of contextual information, and especially in urban areas, a user’s current mode of transport is an important part of her activity. A lot of research has been conducted on automatically recognizing different means of transport, but up to now, no attempt has been made to perform a fine-grained classification of different activities related to travelling by local public transport. In this work, we present an approach to recognize 17 different activities related to travelling by subway. We use only the sensor technology available in modern mobile phones and achieve a high classification accuracy of over 90%, without requiring a specific carrying position of the device. We discuss the usefulness of different sensors and computed features, and identify individual characteristics of the considered activities.},
    Doi = {10.1007/978-3-319-05452-0_10},
    Url = {http://link.springer.com/chapter/10.1007/978-3-319-05452-0_10}
    }
  • L. Schauer, F. Dorfmeister, and M. Maier, "Potentials and Limitations of WIFI-Positioning Using Time-of-Flight," in 4th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2013), 2013, pp. 1-9.
    [BibTeX] [Download PDF]
    @InProceedings{tof,
    Title = {Potentials and Limitations of WIFI-Positioning Using Time-of-Flight},
    Author = {Lorenz Schauer and Florian Dorfmeister and Marco Maier},
    Booktitle = {4th International Conference on Indoor Positioning and Indoor Navigation (IPIN 2013)},
    Year = {2013},
    Pages = {1-9},
    Url = {http://www.cip.ifi.lmu.de/~schauer/publications/WifiTOF.pdf}
    }
  • K. Wiesner, F. Dorfmeister, and C. Linnhoff-Popien, "Privacy-Preserving Calibration for Participatory Sensing," in 10th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2013), Tokyo, Japan, 2013, pp. 276-288.
    [BibTeX]
    @InProceedings{wiesner2013a,
    Title = {Privacy-Preserving Calibration for Participatory Sensing},
    Author = {Kevin Wiesner and Florian Dorfmeister and Claudia Linnhoff-Popien},
    Booktitle = {10th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS 2013)},
    Year = {2013},
    Address = {Tokyo, Japan},
    Month = {December},
    Pages = {276-288},
    Owner = {kwiesner},
    Timestamp = {2013.11.26}
    }

2012

  • F. Dorfmeister, M. Maier, M. Schönfeld, and S. A. W. Verclas, "SmartBEEs: Enabling Smart Business Environments Based on Location Information and Sensor Networks," in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 43-56.
    [BibTeX]
    @InProceedings{smartbeees,
    Title = {SmartBEEs: Enabling Smart Business Environments Based on Location Information and Sensor Networks},
    Author = {Florian Dorfmeister and Marco Maier and Mirco Schönfeld and Stephan A. W. Verclas},
    Booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    Year = {2012},
    Pages = {43-56}
    }
  • M. Dürr, M. Maier, and F. Dorfmeister, "Vegas - A Secure and Privacy-Preserving Peer-to-Peer Online Social Network," in IEEE/ASE Workshop on Security and Privacy of Social Networks (SPSN 2012), in conjunction with The Fourth IEEE/ASE International Conference on Social Computing (SocialCom 2012), 2012, pp. 868-874. doi:10.1109/SocialCom-PASSAT.2012.42
    [BibTeX]
    @InProceedings{vegas,
    Title = {Vegas - A Secure and Privacy-Preserving Peer-to-Peer Online Social Network},
    Author = {Michael Dürr and Marco Maier and Florian Dorfmeister},
    Booktitle = {IEEE/ASE Workshop on Security and Privacy of Social Networks (SPSN 2012), in conjunction with The Fourth IEEE/ASE International Conference on Social Computing (SocialCom 2012)},
    Year = {2012},
    Pages = {868-874},
    Doi = {10.1109/SocialCom-PASSAT.2012.42}
    }
  • M. Kessel, M. Maier, M. Schönfeld, and F. Dorfmeister, "Testing Sensor Fusion Algorithms in Indoor Positioning Scenarios," in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 133-142.
    [BibTeX] [Abstract]
    Location information is the foundation for location based services. However, a cheap and global indoor positioning solution offering a sufficiently high accuracy and precision for most applications is not yet available and detains location based services from indoor areas. This is also due to missing comparability and standards in the field of indoor positioning, resulting in a large number of proprietary research prototypes of varying capabilities. In this paper we present a software environment for testing and comparing sensor fusion algorithms in indoor positioning scenarios. For this purpose an extendable tool for evaluating accuracy, precision, robustness, complexity, and storage is designed and the results from a first implementation presented and discussed.
    @InProceedings{sensorfusiontool,
    Title = {Testing Sensor Fusion Algorithms in Indoor Positioning Scenarios},
    Author = {Moritz Kessel and Marco Maier and Mirco Schönfeld and Florian Dorfmeister},
    Booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    Year = {2012},
    Pages = {133-142},
    Abstract = {Location information is the foundation for location based services. However, a cheap and global indoor positioning solution offering a sufficiently high accuracy and precision for most applications is not yet available and detains location based services from indoor areas. This is also due to missing comparability and standards in the field of indoor positioning, resulting in a large number of proprietary research prototypes of varying capabilities. In this paper we present a software environment for testing and comparing sensor fusion algorithms in indoor positioning scenarios. For this purpose an extendable tool for evaluating accuracy, precision, robustness, complexity, and storage is designed and the results from a first implementation presented and discussed.}
    }
  • M. Maier, F. Dorfmeister, M. Schönfeld, and M. Kessel, "A Tool for Visualizing and Editing Multiple Parallel Tracks of Time Series Data from Sensor Logs," in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 99-108.
    [BibTeX] [Abstract]
    In the last couple of years, the number of smartphone users has proliferated. As smartphones contain a lot of different sensors, research interest in algorithms combining data of several sensors to derive meaningful information about a user's context, e.g. her location, is increasing. Ideas for reasonable algorithms often can be found by looking at examples of raw (or somehow pre-processed) sensor data. Still, the research community lacks a simple means to intuitively work with several parallel tracks of time series data. We present a tool which can be used to visualize and edit time dependent data from various sensors along with ground truth recordings like audio or video files. It is complemented by an optional application for logging all kinds of sensor data on Android devices. The tool has already been used to analyze a large data set containing hundreds of walking traces, intended to improve pedestrian dead reckoning algorithms.
    @InProceedings{paralleltrackstool,
    Title = {A Tool for Visualizing and Editing Multiple Parallel Tracks of Time Series Data from Sensor Logs},
    Author = {Marco Maier and Florian Dorfmeister and Mirco Schönfeld and Moritz Kessel},
    Booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    Year = {2012},
    Pages = {99-108},
    Abstract = {In the last couple of years, the number of smartphone users has proliferated. As smartphones contain a lot of different sensors, research interest in algorithms combining data of several sensors to derive meaningful information about a user's context, e.g. her location, is increasing. Ideas for reasonable algorithms often can be found by looking at examples of raw (or somehow pre-processed) sensor data. Still, the research community lacks a simple means to intuitively work with several parallel tracks of time series data. We present a tool which can be used to visualize and edit time dependent data from various sensors along with ground truth recordings like audio or video files. It is complemented by an optional application for logging all kinds of sensor data on Android devices. The tool has already been used to analyze a large data set containing hundreds of walking traces, intended to improve pedestrian dead reckoning algorithms.}
    }
  • P. Marcus, T. Mair, and F. Dorfmeister, "Compulsory Service Extensions to SIP-Initiated Communication Sessions," in 8th International Conference on Wireless and Mobile Communications (ICWMC 2012), 2012, pp. 124-129.
    [BibTeX]
    @InProceedings{marcus2012compulsory,
    Title = {Compulsory Service Extensions to SIP-Initiated Communication Sessions},
    Author = {Philipp Marcus and Thomas Mair and Florian Dorfmeister},
    Booktitle = {8th International Conference on Wireless and Mobile Communications (ICWMC 2012)},
    Year = {2012},
    Pages = {124-129},
    Publisher = {ThinkMind},
    Owner = {pmarcus}
    }
  • M. Schönfeld, M. Werner, and F. Dorfmeister, "Location-based Access Control Providing One-Time Passwords Through 2D Barcodes," in 9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste, 2012, pp. 165-168.
    [BibTeX] [Abstract] [Download PDF]
    Location-based Access Control often relies a location proof, which ensures that a specific user is at a specific location. These locations are most often inferred from measurements. As a consequence, such systems are never trustworthy. An attacker can simply fake sensor measurements or even sensor data in absence of a trusted measurement module. Moreover, the measurement data is typically stable over time at a fixed location and can thus be replayed at later times. With this paper, we propose a system, which can provide functionality for a location proof, which does not rely on measurements and does not suffer from replay attacks. Therefore, a self-contained system is generating signed one-time passwords and communicates them via 2D barcodes for authentication of camera-enabled devices being in a specific location.
    @InProceedings{qrcodelocationproof,
    Title = {Location-based Access Control Providing One-Time Passwords Through 2D Barcodes},
    Author = {Mirco Schönfeld and Martin Werner and Florian Dorfmeister},
    Booktitle = {9. GI/ITG KuVS Fachgespräch Ortsbezogene Anwendungen und Dienste},
    Year = {2012},
    Pages = {165-168},
    Abstract = {Location-based Access Control often relies a location proof, which ensures that a specific user is at a specific location. These locations are most often inferred from measurements. As a consequence, such systems are never trustworthy. An attacker can simply fake sensor measurements or even sensor data in absence of a trusted measurement module. Moreover, the measurement data is typically stable over time at a fixed location and can thus be replayed at later times. With this paper, we propose a system, which can provide functionality for a location proof, which does not rely on measurements and does not suffer from replay attacks. Therefore, a self-contained system is generating signed one-time passwords and communicates them via 2D barcodes for authentication of camera-enabled devices being in a specific location.},
    File = {2012-LBAC.pdf:http\://publications.mircoschoenfeld.de/2012-LBAC.pdf:PDF},
    Url = {http://publications.mircoschoenfeld.de/2012-LBAC.pdf}
    }