own-publications.bib

@inproceedings{paper-koi2002,
  author = {Michael Affenzeller and Rene Mayrhofer},
  title = {Generic Heuristics for Combinatorial Optimization Problems},
  booktitle = {Proceedings of the 9th International Conference on Operational Research
	({KOI2002})},
  year = {2002},
  pages = {83--92},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/koi2002.ps},
  isbn = {953-6931-08-7},
  pubtype = {conference}
}
@inproceedings{paper-sobs05,
  author = {Alois Ferscha and Manfred Hechinger and Rene Mayrhofer and Ekaterina
	Chtcherbina and Marquardt Franz and Marcos dos~Santos~Rocha and Andreas
	Zeidler},
  title = {Bridging the Gap with {P2P} Patterns},
  booktitle = {Proceedings of the Workshop on Smart Object Systems},
  year = {2005},
  month = {September},
  note = {in conjunction with the Seventh International Conference on Ubiquitous
	Computing ({UbiComp} 2005)},
  abstract = {Abstract The design principles of pervasive computing software architectures
	are widely driven by the need for opportunistic interaction among
	distributed, mobile and heterogeneous entities in the absence of
	global knowledge and naming conventions. Peer-to-Peer (P2P) frameworks
	have evolved, abstracting the access to shared, while distributed
	information. To bridge the architectural gap between P2P applications
	and P2P frameworks we propose patterns as an organizational schema
	for P2P based software systems. Our Peer-it hardware platform is
	used to demonstrate an application in the domain of flexible manufacturing
	systems.},
  day = {11},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/SOBS2005-P2P-Patterns.pdf},
  eventurl = {http://ubicomp.lancs.ac.uk/workshops/sobs05/},
  pubtype = {workshop}
}
@inproceedings{paper-mdc2004,
  author = {Alois Ferscha and Manfred Hechinger and Rene Mayrhofer and Roy Oberhauser},
  title = {A Light-Weight Component Model for Peer-to-Peer Applications},
  booktitle = {Proceedings {MDC04}: 2nd International Workshop on Mobile Distributed
	Computing},
  year = {2004},
  pages = {520--527},
  month = {March},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  abstract = {Mobile Peer-to-Peer (P2P) computing applications involve collections
	of heterogeneous and resource-limited devices (such as PDAs or embedded
	sensor-actuator systems), typically operated in ad-hoc completely
	decentralized networks and without requiring dedicated infrastructure
	support. Short-range wireless communication technologies together
	with P2P networking capabilities on mobile devices are responsible
	for a proliferation of such applications, yet these applications
	are often complex and monolithic in nature due to the lack of lightweight
	component/container support in these resource-constrained devices.
	
	In this paper we describe our lightweight software component model
	P2Pcomp that addresses the development needs for mobile P2P applications.
	An abstract, flexible, and high-level communication mechanism among
	components is developed via a ports concept, supporting protocol
	independence, location independence, and (a)synchronous invocations;
	dependencies are not hard-coded in the components, but can be defined
	at deployment or runtime, providing late-binding and dynamic rerouteability
	capabilities. Peers can elect to provide services as well as consume
	them, services can migrate between containers, and services are ranked
	to support Quality-of-Service choices. Our lightweight container
	realization leverages the OSGi platform and can utilize various P2P
	communication mechanisms such as JXTA. A “smart space” application
	scenario demonstrates how P2Pcomp supports flexible and highly tailorable
	mobile P2P applications.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MDC2004-P2P-components.pdf},
  eventurl = {http://www4.comp.polyu.edu.hk/~mdc04/},
  location = {Tokio},
  pubtype = {workshop}
}
@inproceedings{paper-pervasive2004-digitalaura,
  author = {Alois Ferscha and Manfred Hechinger and Rene Mayrhofer and Marcos
	dos~Santos~Rocha and Marquardt Franz and Roy Oberhauser},
  title = {{D}igital {A}ura},
  booktitle = {Advances in Pervasive Computing},
  year = {2004},
  editor = {A. Ferscha and H. H\"ortner and G. Kotsis},
  volume = {176},
  pages = {405--410},
  month = {April},
  publisher = {Austrian Computer Society {(OCG)}},
  note = {part of the Second International Conference on Pervasive Computing
	({Pervasive 2004})},
  abstract = {Smart space and smart appliances, i.e. wirelessly ad-hoc networked,
	mobile, autonomous special purpose computing devices, providing largely
	invisible support and context-aware services have started to populate
	the real world and our daily lives. In such a world, where literally
	everything is connected to everything with invisible, wireless data
	links, we need new styles on how humans and things can interact.
	We have proposed a ``spontaneous interaction'' thought model, in
	which things start to interact once they reach physical proximity
	to each other: Explained using the metaphor of an ``aura'', which
	like a subtle invisible emanation or exhalation radiates from the
	center of an object into its surrounding, a ``digital aura'' is built
	on technologies like Bluetooth radio, RFID or IrDA together with
	an XML based profile description, such that if an object detects
	the proximity (e.g. radio signal strength) of another object, it
	starts exchanging and comparing profile data, and, upon sufficient
	``similarity'' of the two profiles, starts to interact with that
	object. A ``digital aura'' depending on the implementation technology,
	is dense in the center of the object, and thins out towards its surrounding
	until it is no longer sensible by others. Profiles described as semi-structured
	data and attached to the object, can be matched by a structural and
	semantic analysis. Peer-to-peer concepts can then be used to implement
	applications on top of the digital aura model for spontaneous interaction.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2004-Video-DigitalAura.pdf},
  eventurl = {http://www.pervasive2004.org/program_videonight.php},
  isbn = {3-85403-176-9},
  pubtype = {conference},
  videourl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2004-Video-DigitalAura.mpg}
}
@inproceedings{paper-eurocast2013-face-unlock,
  author = {Rainhard Findling and Rene Mayrhofer},
  title = {Towards Secure Personal Device Unlock using Stereo Camera Pan Shots},
  booktitle = {Proc. {EUROCAST 2013}: 14th International Conference on ComputerAided
	Systems Theory},
  pages = {417--425},
  year = {2013},
  series = {LNCS},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  day = {10--15},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/EUROCAST2013-Stereo-Camera-Pan-Shots.pdf},
  eventurl = {http://www.fh-ooe.at/mcpt2013/},
  location = {Las Palmas, Gran Canaria},
  pubtype = {conference}
}
@inproceedings{paper-momm2012-face-detection,
  author = {Rainhard Findling and Rene Mayrhofer},
  title = {Towards Face Unlock: On the Difficulty of Reliably Detecting Faces
	on Mobile Phones},
  booktitle_short = {Proc. {MoMM} 2012},
  year = {2012},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  booktitle = {Proc. {MoMM} 2012: 10th International Conference on Advances in Mobile
	Computing and Multimedia},
  day = {3--5},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2012-Mobile-Phone-Face-Detection.pdf},
  eventurl = {http://iiwas.org/conferences/momm2012/},
  location = {Bali, Indonesia},
  pubtype = {conference}
}
@inproceedings{paper-momm2013-face-segmentation,
  author = {Rainhard Findling and Fabian Wenny and Clemens Holzmann and Rene
	Mayrhofer},
  title = {Range Face Segmentation: Face Detection and Segmentation for Authentication
	in Mobile Device Range Images},
  booktitle_short = {Proc. {MoMM} 2013},
  year = {2013},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Face detection (finding faces of different perspectives in images)
	is an important task as prerequisite to face recognition. This is
	especially difficult in the mobile domain, as bad image quality and
	illumination conditions lead to overall reduced face detection rates.
	Background information still present in segmented faces and unequally
	normalized faces further decrease face recognition rates. We present
	a novel approach to robust single upright face detection and segmentation
	from different perspectives based on range information (pixel values
	corresponding to the camera-object distance). We use range template
	matching for finding the face's coarse position and
	gradient vector flow (GVF) snakes for precisely segmenting faces.
	We further evaluate our approach on range faces from the u'smile
	face database, then perform face recognition using the segmented
	faces to evaluate and compare our approach with previous research.
	Results indicate that range template matching might be a good approach
	to finding a single face; in our tests we achieved an error free
	detection rate and average recognition rates above 98\%/96\% for
	color/range images.},
  booktitle = {Proc. {MoMM} 2013: 11th International Conference on Advances in Mobile
	Computing and Multimedia},
  pages = {260--269},
  day = {2--4},
  eventurl = {http://www.iiwas.org/conferences/momm2013/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2013-Range-Face-Segmentation.pdf},
  keywords = {face detection, face segmentation, mobile device, Range images, snakes,
	template matching},
  location = {Vienna, AT},
  pubtype = {conference}
}
@inproceedings{paper-momm2012-accelerometer-authentication,
  author = {Bogdan Groza and Rene Mayrhofer},
  title = {{SAPHE} - Simple Accelerometer based wireless Pairing with HEuristic
	trees},
  booktitle = {Proc. {MoMM} 2012: 10th International Conference on Advances in Mobile
	Computing and Multimedia},
  pages = {161--168},
  year = {2012},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  day = {3--5},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2012-SAPHE.pdf},
  eventurl = {http://iiwas.org/conferences/momm2012/},
  location = {Bali, Indonesia},
  pubtype = {conference}
}
@inproceedings{paper-iwssi2011,
  author = {Sebastian H\"obarth and Rene Mayrhofer},
  title = {A framework for on-device privilege escalation exploit execution
	on {Android}},
  booktitle_short = {Proc. {IWSSI/SPMU 2011}, colocated with {Pervasive 2011}},
  year = {2011},
  month = {June},
  abstract = {Exploits on mobile phones can be used for various reasons; a benign
	one may be to achieve system-level access on a device that was locked
	by the manufacturer or service provider (also known as `jailbreaking'
	or `rooting'), while potentially malicious reasons are manifold.
	Independently of the use case however, a specific exploit is not
	sufficient to achieve the desired access rights. Typically, exploits
	provide \emph{temporary privilege escalation} immediately after their
	execution. To provide additional access to applications, \emph{permanent
	privilege escalation} is required -- in the benign case, including
	secure access control for the user to decide which (parts of) applications
	are granted elevated access. In this paper, we present a framework
	that can use arbitrary temporary exploits on Android devices to achieve
	permanent `root' capabilities for select (parts of) applications.},
  booktitle = {Proc. {IWSSI/SPMU 2011}: 3rd International Workshop on Security and
	Privacy in Spontaneous Interaction and Mobile Phone Use, colocated
	with {Pervasive 2011}},
  booktitle_short = {Proc. {IWSSI/SPMU 2011}},
  day = {12},
  disabled_note = {available online at \url{http://www.medien.ifi.lmu.de/iwssi2011/}},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/IWSSI2011-Android-Exploit-Framework.pdf},
  eventurl = {http://www.medien.ifi.lmu.de/iwssi2011/},
  location = {San Francisco, CA, USA},
  pubtype = {workshop}
}
@inproceedings{paper-momm2013-javacard-ecosystem,
  author = {Michael H\"olzl and Rene Mayrhofer and Michael Roland},
  title = {Requirements for an Open Ecosystem for Embedded Tamper Resistant
	Hardware on Mobile Devices},
  booktitle_short = {MoMM 2013: 11th International Conference on Advances in Mobile Computing
	and Multimedia},
  year = {2013},
  pages = {249--252},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Insufficient security and privacy on mobile devices have made it difficult
	to utilize sensitive systems like mobile banking, mobile credit cards,
	mobile ticketing or mobile passports. Solving these challenges in
	security and privacy, could result in better mobility and a higher
	level of confidence for the end-user services in such systems. Our
	approach for a higher security and privacy level on mobile devices
	introduces an open ecosystem for tamper resistant hardware. Big advantages
	of these modules are the protection against unauthorized access and
	the on-device cryptographic operations they can perform. In this
	paper, we analyse the requirements and performance restrictions of
	these hardware modules and present an interface concept for a tight
	integration of their security features. },
  booktitle = {Proc. {MoMM} 2013: 11th International Conference on Advances in Mobile
	Computing and Multimedia},
  day = {2--4},
  eventurl = {http://www.iiwas.org/conferences/momm2013/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2013-Javacard-Open-Ecosystem.pdf},
  isbn = {978-1-4503-2106-8},
  keywords = {open ecosystem, secure element, Tamper resistant hardware, transparent
	secure channel, trusted execution environment},
  location = {Vienna, AT},
  pubtype = {conference}
}
@inproceedings{paper-ubicomp2014adjunct-mobile-device-locking-usage,
  author = {Daniel Hintze and Rainhard D. Findling and Muhammad Muaaz and Sebastian Scholz and Ren\'e Mayrhofer},
  title = {Diversity in Locked and Unlocked Mobile Device Usage},
  booktitle_short = {Adjunct proc. {UbiComp} 2014},
  booktitle = {Proceedings of the 2014 ACM International Joint Conference on Pervasive and Ubiquitous Computing: Adjunct Publication ({UbiComp} 2014)},
  year = {2014},
  pages = {379--384},
  publisher = {ACM Press},
  eventurl = {http://ubicomp.org/ubicomp2014/},
  documenturl = {http://dl.acm.org/citation.cfm?id=2641697},
  doi = {10.1145/2638728.2641697},
  isbn = {978-1-4503-3047-3},
  abstract = {We analyze locked and unlocked mobile device usage of 1 960 Android smartphones. Based on approximately 10TB of mobile device data logs collected by the Device Analyzer project, we derive 6.9 million usage sessions using a screen power state machine based approach. From these session we examine the number of interactions per day, the average interaction duration as well as the total daily device usage time. Findings indicate that on average users interact with their devices 117 minutes a day, separated over 57 interactions -- while unlocking their device only 43% of the time (e. g. to check for notifications).},
  note = {\textbf{winner of UbiComp/ISWC 2014 Programming Competition}},
  pubtype = {workshop}
}
@inproceedings{paper-momm2014-mobile-device-usage,
  author = {Daniel Hintze and Rainhard D. Findling and Sebastian Scholz and Ren\'e Mayrhofer},
  title = {Mobile Device Usage Characteristics: The Effect of Context and Form Factor on Locked and Unlocked Usage},
  booktitle_short = {Proc. {MoMM} 2014},
  booktitle = {Proc. {MoMM} 2014: 12th International Conference on Advances in Mobile Computing and Multimedia},
  year = {2014},
  pages = {105--114},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Smartphones and tablets are an indispensable part of modern
communication and people spend considerable time interacting with their devices every day. While substantial research
has been conducted concerning smartphone usage, little is
known about how tablets are used. This paper studies mobile
device usage characteristics like session length, interaction
frequency, and daily usage in locked and unlocked state with
respect to location context. Based on logs from 1,585 Android devices (470 years of total usage time), we derive and
analyze 23 million usage sessions. We found that devices
remain locked for 60\% of the interactions and usage at home
occurs twice as frequent as at work. With an average of 58
interactions per day, smartphones are used twice as often as
tablets, while tablet sessions are 2.5 times longer, resulting
in almost equal aggregated daily usage. We conclude that usage session characteristics differ considerably between tablets
and smartphones.},
  day = {8--10},
  eventurl = {http://www.iiwas.org/conferences/momm2014/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2014-Mobile-Device-Usage.pdf},
  isbn = {978-1-4503-3008-4},
  doi = {10.1145/2684103.2684156},
  keywords = {Daily interactions, Device unlocking, Locked usage, Session length, Smartphone, Tablet, Usage session, User context},
  location = {Kaohsiung, Taiwan},
  pubtype = {conference}
}
@inproceedings{paper-momm2014-javacard-authentication,
  author = {Michael H\"olzl and Endalkachew Asnake and Ren\'e Mayrhofer and Michael Roland},
  title = {Mobile Application to Java Card Applet Communication using a Password-authenticated Secure Channel},
  booktitle_short = {Proc. {MoMM} 2014},
  booktitle = {Proc. {MoMM} 2014: 12th International Conference on Advances in Mobile Computing and Multimedia},
  year = {2014},
  pages = {147--156},
  month = {Dec.},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {With the increasing popularity of security and privacy sensitive systems on mobile devices, such as mobile banking,
mobile credit cards, mobile ticketing, or mobile digital identities, challenges for the protection of personal and security
sensitive data of these use cases emerged. A common approach for the protection of sensitive data is to use additional
hardware such as smart cards or secure elements. The communication between such dedicated hardware and back-end
management systems uses strong cryptography. However,
the data transfer between applications on the mobile device
and so-called applets on the dedicated hardware is often
either unencrypted (and interceptable by malicious software)
or encrypted with static keys stored in applications. To
address this issue we present a solution for fine-grained secure application-to-applet communication based on Secure
Remote Password (SRP-6a), an authenticated key agreement
protocol, with a user-provided password at run-time. By
exploiting the Java Card cryptographic API and minor adaptations to the protocol, which do not affect the security, we
were able to implement this scheme on Java Cards with
reasonable computation time.},
  day = {8--10},
  eventurl = {http://www.iiwas.org/conferences/momm2014/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2014-Javacard-Authentication.pdf},
  isbn = {978-1-4503-3008-4},
  doi = {10.1145/2684103.2684128},
  keywords = {Java Card, smart card, SRP-6a, secure channel, secure element, mobile devices},
  location = {Kaohsiung, Taiwan},
  pubtype = {conference}
}
@inproceedings{paper-momm2014-gait-authentication,
  author = {Muhammad Muaaz and Ren\'e Mayrhofer},
  title = {Orientation Independent Cell Phone Based Gait Authentication},
  booktitle_short = {Proc. {MoMM} 2014},
  booktitle = {Proc. {MoMM} 2014: 12th International Conference on Advances in Mobile Computing and Multimedia},
  year = {2014},
  pages = {161--164},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Gait authentication using a cell phone based accelerometer sensor offers an unobtrusive, user-friendly, and periodic
way of authenticating individuals on their cell phones. In
this study, we present an approach to deal with inevitable
errors induced by continuously changing sensor orientation
and other noise under a realistic scenario (when the phone
is placed inside the trouser pockets and the user is walking)
by using the magnitude data of tri-axes accelerometer and
wavelet based noise elimination modules. This study utilizes
a gait data set of 35 participants collected at their respective normal walking pace in two different sessions with an
average gap of 25 days between the sessions.},
  day = {8--10},
  eventurl = {http://www.iiwas.org/conferences/momm2014/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2014-Orientation-Independent-Gait-Authentication.pdf},
  isbn = {978-1-4503-3008-4},
  doi = {10.1145/2578726.2578744},
  keywords = {accelerometer, gait recognition, segmentation, variance, wavelets},
  location = {Kaohsiung, Taiwan},
  pubtype = {conference}
}
@inproceedings{paper-momm2014-shake-unlock,
  author = {Rainhard D. Findling and Muhammad Muaaz and Daniel Hintze and Ren\'e Mayrhofer},
  title = {ShakeUnlock: Securely Unlock Mobile Devices by Shaking them Together},
  booktitle_short = {Proc. {MoMM} 2014},
  booktitle = {Proc. {MoMM} 2014: 12th International Conference on Advances in Mobile Computing and Multimedia},
  year = {2014},
  pages = {165--174},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {ABSTRACT
The inherent weakness of typical mobile device unlocking
approaches (PIN, password, graphic pattern) is that they
demand time and attention, leading a majority of end users
to disable them, effectively lowering device security.

We propose a method for unlocking mobile devices by
shaking them together, implicitly passing the unlocked state
from one device to another. One obvious use case includes a
locked mobile phone and a wrist watch, which remains unlocked as long as strapped to the user’s wrist. Shaking both
devices together generates a one-time unlocking event for
the phone without the user interacting with the screen. We
explicitly analyze the usability critical impact of shaking duration with respect to the level of security. Results indicate
that unlocking is possible with a true match rate of 0.795
and true non match rate of 0.867 for a shaking duration as
short as two seconds.},
  day = {8--10},
  eventurl = {http://www.iiwas.org/conferences/momm2014/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2014-Shake-Unlock-on-Wrist.pdf},
  isbn = {978-1-4503-3008-4},
  doi = {10.1145/2684103.2684122},
  keywords = {accelerometer; authentication; frequency domain; mobile devices; shaking; time series analysis; usability;},
  location = {Kaohsiung, Taiwan},
  note = {\textbf{awarded best MoMM 2014 paper}},
  pubtype = {conference}
}
@inproceedings{paper-iiwas2014-quaternion-derotation,
  author = {Ren\'e Mayrhofer and Helmut Hlavacs and Rainhard Dieter Findling},
  title = {Optimal Derotation of Shared Acceleration Time Series by Determining Relative Spatial Alignment},
  booktitle_short = {Proc. {iiWAS} 2014},
  booktitle = {Proc. {iiWAS} 2014: 16th International Conference on Information Integration and Web-based Applications \& Services},
  year = {2014},
  pages = {71--78},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Detecting if two or multiple devices are moved together is
an interesting problem for different applications. However,
these devices may be aligned arbitrarily with regards to each
other, and the three dimensions sampled by their respective
local accelerometers can therefore not be directly compared.
The typical approach is to ignore all angular components
and only compare overall acceleration magnitudes -- with
the obvious disadvantage of discarding potentially useful information. In this paper, we contribute a method to ana-
lytically determine relative spatial alignment of two devices
based on their acceleration time series. Our method uses
quaternions to compute the optimal rotation with regards to
minimizing the mean squared error. The implication is that
the reference system of one device can be (locally and independently) aligned with the other, and thus that all three
dimensions can consequently be compared for more accurate classification. Based on real-world experimental data
from smart phones and smart watches shaken together, we
demonstrate the effectiveness of our method with a magnitude squared coherence metric, for which we show an im-
proved EER of 0.16 (when using derotation) over an EER
of 0.18 (when not using derotation).},
  day = {4--6},
  eventurl = {http://www.iiwas.org/conferences/iiwas2014/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/iiWAS2014-Quaternion-Derotation.pdf},
  isbn = {978-1-4503-3001-5},
  keywords = {Accelerometer time series; spatial alignment; quaternion rotation},
  location = {Hanoi, Vietnam},
  note = {\textbf{awarded best iiWAS 2014 paper}},
  pubtype = {conference}
}
@inproceedings{paper-iiwas2011,
  author = {Paul Klingelhuber and Rene Mayrhofer},
  title = {{Private Notes}: Encrypted XML Notes Synchronization and Sharing
	with Untrusted Web Services},
  booktitle = {Proc. {iiWAS2011}: 13th International Conference on Information Integration
	and Web-based Applications \& Services},
  year = {2011},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Personal notes, even when shared with others, often contain highly
	sensitive information. From a security and privacy point of view,
	currently available (web) services that upload such personal notes
	to potentially untrusted third party servers are therefore problematic
	and we suggest to encrypt all notes before transferring them from
	the user's personal device. However, synchronization and sharing
	of encrypted data is a non-trivial issue, because conflict resolution
	and merging algorithms need to be applied to plain-text content.
	With \emph{Private Notes}, we propose an architecture for client-side
	encryption, merge, and conflict handling of personal notes stored
	in XML format. We adopt the OpenPGP standard for symmetric and asymmetric
	encryption and WebDAV for synchronizing and sharing notes on arbitrary
	web servers. Specific implementations in the form of a plug-in for
	the Tomboy desktop note taking application and the Android and iOS
	mobile platforms demonstrate the ease of use of encrypted notes sharing.},
  acceptancerate = {26\%},
  booktitle_short = {Proc. {iiWAS2011}},
  day = {5--7},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/iiWAS2011-PrivateNotes.pdf},
  eventurl = {http://www.iiwas.org/conferences/iiwas2011/},
  isbn = {978-1-4503-0784-0},
  owner = {rene},
  pubtype = {conference}
}
@inproceedings{paper-ucse2010,
  author = {Vikash Kumar and Anna Fensel and Slobodanka Tomic and Rene Mayrhofer
	and Tassilo Pellegrini},
  title = {User Created Machine-readable Policies for Energy Efficiency in Smart
	Homes},
  booktitle = {Proc. {UCSE} 2010, co-located with Ubicomp 2010},
  year = {2010},
  month = {September},
  abstract = {The project SESAME utilizes smart metering, building automation and
	policy-based reasoning to support home owners and building managers
	in saving energy and in optimizing their energy costs while maintaining
	their preferred quality of living. In this paper, we present how
	user-created policies are being applied to develop a system of least
	interference that supports the user in gaining awareness about energy
	consumption habits and saving potentials. Proposed concepts are currently
	being implemented and validated in an extensible demonstrator platform
	which provides a proof-of-concept for an innovative technical solution.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/UCSE2010-SESAME.pdf},
  eventurl = {http://www.hcilab.org/events/ucse2010/},
  location = {Copenhagen, Denmark},
  pubtype = {workshop}
}
@inproceedings{paper-eurocast2011-mda2,
  author = {Michael Lettner and Michael Tschernuth and Rene Mayrhofer},
  title = {Mobile Platform Architecture Review: {Android}, {iPhone}, {Qt}},
  booktitle = {Proc. {EUROCAST 2011}: 13th International Conference on Computer
	Aided Systems Theory, Part II},
  year = {2011},
  volume = {6928},
  series = {LNCS},
  pages = {545--552},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  day = {6--11},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/EUROCAST2011-MDA-Platforms.pdf},
  editors = {Alexis Quesada-Arencibia and José Carlos Rodríguez and Roberto Moreno-Díaz
	jr. and Roberto Moreno-Díaz},
  eventurl = {http://www.fh-hagenberg.at/mcpt2011},
  location = {Las Palmas, Gran Canaria},
  pubtype = {conference}
}
@inproceedings{paper-models2011,
  author = {Michael Lettner and Michael Tschernuth and Rene Mayrhofer},
  title = {A Critical Review of Applied MDA for Embedded Devices: Identification
	of Problem Classes and Discussing Porting Efforts in Practice},
  booktitle = {Proc. {MODELS 2011}: ACM/IEEE 14th International Conference on Model
	Driven Engineering Languages and Systems},
  year = {2011},
  series = {LNCS},
  month = {October},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  abstract = {Model-driven development (MDD) has seen wide application in research,
	but still has limitations in real world industrial projects. One
	project which applies such MDD principles is about developing the
	software of a feature phone. While advantages seem to outweigh any
	disadvantages in theory, several problems arise when applying the
	model-driven methodology in practice. Problems when adopting this
	approach are shown as well as a practical solution to utilize one
	of the main advantages of MDD---portability. Issues that originate
	from using a tool which supports a model-driven approach are presented.
	A conclusion sums up the personal experiences made when applying
	MDD in a real world project.},
  day = {16--21},
  eventurl = {http://www.modelsconference.org/},
  location = {Wellington, New Zealand},
  pubtype = {conference}
}
@inproceedings{paper-momm2011-lettner,
  author = {Michael Lettner and Michael Tschernuth and Rene Mayrhofer},
  title = {Feature interaction analysis in mobile phones: on the borderline
	between application functionalities and platform components},
  booktitle = {Proc. {MoMM} 2011: 9th International Conference on Advances in Mobile
	Computing and Multimedia},
  year = {2011},
  pages = {268--272},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  day = {5--7},
  isbn = {978-1-4503-0785-7},
  location = {Ho Chi Minh City, Vietnam},
  pubtype = {conference}
}
@incollection{paper-pervasive2004-doctoral,
  author = {Rene Mayrhofer},
  title = {An Architecture for Context Prediction},
  booktitle = {Advances in Pervasive Computing},
  publisher = {Austrian Computer Society {(OCG)}},
  year = {2004},
  editor = {A. Ferscha and H. H\"ortner and G. Kotsis},
  volume = {176},
  pages = {65--72},
  month = {April},
  note = {part of the Second International Conference on Pervasive Computing
	({PERVASIVE 2004})},
  abstract = {Today's information appliances are usually very powerful, featuring
	local storage and processing power, communication technology and
	supporting many different applications. They are either mobile, like
	laptop computers, handheld devices, mobile phones or wearables, or
	fixed, like TV set-top boxes, home entertainment centers or even
	whole rooms equipped with various interacting devices; but most of
	them have various hardware components that can be used as sensors
	for querying the environment. By exploiting these sensors, it is
	possible to make devices context aware and thus adaptive to the current
	user's situation. This paper presents the basic structure of a framework
	which eases the implementation of context aware applications by providing
	the current and future, predicted context.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2004-Doctoral-Architecture-Context-Prediction.pdf},
  eventurl = {http://www.pervasive2004.org/program_doctoralcolloquim.php},
  isbn = {3-85403-176-9},
  pubtype = {other-refereed}
}
@inproceedings{paper-echise2005,
  author = {Rene Mayrhofer},
  title = {Context Prediction based on Context Histories: Expected Benefits,
	Issues and Current State-of-the-Art},
  booktitle = {Proc. {ECHISE 2005}: 1st International Workshop on Exploiting Context
	Histories in Smart Environments},
  year = {2005},
  editor = {T. Prante and B. Meyers and G. Fitzpatrick and L.~D. Harvel},
  month = {May},
  note = {part of the Third International Conference on Pervasive Computing
	({PERVASIVE 2005})},
  abstract = {This paper presents the topic of context prediction as one possibility
	to exploit context histories. It lists some expected benefits of
	context prediction for certain application areas and discusses the
	associated issues in terms of accuracy, fault tolerance, unobtrusive
	operation, user acceptance, problem complexity and privacy. After
	identifying the challenges in context prediction, a first approach
	is summarized briefly. This approach, when applied to recorded context
	histories, builds upon three steps of a previously introduced software
	architecture: feature extraction, classification and prediction.
	Open issues remain in the areas of prediction accuracy, dealing with
	limited resources, sharing of context information and user studies.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/ECHISE2005-Context-Prediction-based-on-Context-Histories.pdf},
  eventurl = {http://www.ipsi.fraunhofer.de/ambiente/echise2005/},
  pubtype = {workshop}
}
@inproceedings{paper-tsp2013,
  author = {Rene Mayrhofer},
  title = {When Users Cannot Verify Digital Signatures: On the Difficulties
	of Securing Mobile Devices},
  booktitle_short = {Proc. {HPCC} 2013},
  year = {2013},
  month = {November},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  booktitle = {Proc. {HPCC} 2013: 15th IEEE International Conference on High Performance
	Computing and Communications},
  pages = {1579--1584},
  day = {13--15},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/TSP2013-Mobile-Device-Security-Difficulties.pdf},
  eventurl = {http://trust.csu.edu.cn/conference/tsp2013/},
  location = {Zhangjiajie, China},
  pubtype = {conference}
}
@inproceedings{paper-esas2007,
  author = {Rene Mayrhofer},
  title = {The Candidate Key Protocol for Generating Secret Shared Keys From
	Similar Sensor Data Streams},
  booktitle = {Proc. {ESAS 2007}: 4th European Workshop on Security and Privacy
	in Ad hoc and Sensor Networks},
  year = {2007},
  volume = {4572},
  series = {LNCS},
  pages = {1--15},
  month = {July},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  abstract = {Secure communication over wireless channels necessitates authentication
	of communication partners to prevent man-in-the-middle attacks. For
	spontaneous interaction between independent, mobile devices, no a
	priori information is available for authentication purposes. However,
	traditional approaches based on manual password input or verification
	of key fingerprints do not scale to tens to hundreds of interactions
	a day, as envisioned by future ubiquitous computing environments.
	One possibility to solve this problem is authentication based on
	similar sensor data: when two (or multiple) devices are in the same
	situation, and thus experience the same sensor readings, this constitutes
	shared, (weakly) secret information. This paper introduces the \emph{Candidate
	Key Protocol} (CKP) to interactively generate secret shared keys
	from similar sensor data streams. It is suitable for two-party and
	multi-party authentication, and supports opportunistic authentication.},
  day = {2--3},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/ESAS2007-Candidate-Key-Protocol.pdf},
  eventurl = {http://www.cl.cam.ac.uk/~twm29/esas/},
  isbn = {978-3-540-73274-7},
  location = {Cambridge, UK},
  pubtype = {workshop},
  short_booktitle = {Proc. {ESAS 2007}}
}
@inproceedings{paper-eurocast2007,
  author = {Rene Mayrhofer},
  title = {Extending the Growing Neural Gas Classifier for Context Recognition},
  booktitle = {Proc. {EUROCAST} 2007: 11th International Conference on Computer
	Aided Systems Theory},
  year = {2007},
  volume = {4739},
  series = {LNCS},
  pages = {920--927},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  abstract = {Context awareness is one of the building blocks of many applications
	in pervasive computing. Recognizing the current context of a user
	or device, that is, the situation in which some action happens, often
	requires dealing with data from different sensors, and thus different
	domains. The Growing Neural Gas algorithm is a classification algorithm
	especially designed for un-supervised learning of unknown input distributions;
	a variation, the Lifelong Growing Neural Gas (LLGNG), is well suited
	for arbitrary long periods of learning, as its internal parameters
	are self-adaptive. These features are ideal for automatically classifying
	sensor data to recognize user or device context. However, as most
	classification algorithms, in its standard form it is only suitable
	for numerical input data. Many sensors which are available on current
	information appliances are nominal or ordinal in type, making their
	use difficult. Additionally, the automatically created clusters are
	usually too fine-grained to distinguish user-context on an application
	level. This paper presents general and heuristic extensions to the
	LLGNG classifier which allow its direct application for context recognition.
	On a real-world data set with two months of heterogeneous data from
	different sensors, the extended LLGNG classifier compares favorably
	to k-means and SOM classifiers.},
  day = {12--16},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Eurocast2007-Extending-GNG.pdf},
  eventurl = {http://www.cl.cam.ac.uk/~twm29/esas/},
  isbn = {978-3-540-75866-2},
  issn = {0302-9743},
  location = {Las Palmas, Gran Canaria, ES},
  pubtype = {workshop}
}
@inproceedings{paper-persec2007,
  author = {Rene Mayrhofer},
  title = {Towards an Open Source Toolkit for Ubiquitous Device Authentication},
  booktitle = {Workshops Proc. {PerCom 2007}: 5th {IEEE} International Conference
	on Pervasive Computing and Communications},
  year = {2007},
  pages = {247--252},
  month = {March},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  note = {Track {PerSec 2007}: 4th {IEEE} International Workshop on Pervasive
	Computing and Communication Security},
  abstract = {Most authentication protocols designed for ubiquitous computing environments
	try to solve the problem of intuitive, scalable, secure authentication
	of wireless communication. Due to the diversity of requirements,
	protocols tend to be implemented within specific research prototypes
	and can not be used easily in other applications. We propose to develop
	a common toolkit for ubiquitous device authentication to foster wide
	usability of research results. This paper outlines design goals and
	presents a first, freely available implementation.},
  day = {19--23},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/PerSec2007-Towards-OpenUAT.pdf},
  eventurl = {http://www.cl.cam.ac.uk/~fms27/persec-2007/},
  isbn = {0-7695-2788-4},
  location = {White Plains, New York, USA},
  pubtype = {workshop}
}
@inproceedings{paper-twuc2006,
  author = {Rene Mayrhofer},
  title = {A Context Authentication Proxy for {IPSec} using Spatial Reference},
  booktitle = {Proc. {TwUC} 2006: 1st International Workshop on Trustworthy Ubiquitous
	Computing},
  year = {2006},
  pages = {449--462},
  month = {December},
  publisher = {Austrian Computer Society ({OCG})},
  abstract = {Spontaneous interaction in ad-hoc networks is often desirable not
	only between users or devices in direct contact, but also with devices
	that are accessible only via a wireless network. Secure communication
	with such devices is difficult because of the required authentication,
	which is often either password- or certificate-based. An intuitive
	alternative is context-based authentication, where device authenticity
	is verified by shared context, and often by direct physical evidence.
	Devices that are physically separated can not experience the same
	context and can thus not benefit directly from context authentication.
	We introduce a \emph{context authentication proxy} that is pre-authenticated
	with one of the devices and can authenticate with the other by shared
	context. This concept is applicable to a wide range of application
	scenarios, context sensing technologies, and trust models. We show
	its practicality in an implementation for setting up IPSec connections
	based on spatial reference. Our specific scenario is ad-hoc access
	of mobile devices to secure 802.11 WLANs using a PDA as authentication
	proxy.},
  day = {6},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/TwUC-IPSec-Context-Authentication-Proxy.pdf},
  eventurl = {http://www.iiwas.org/conferences/twuc2006/},
  isbn = {3-85403-216-1},
  location = {Yogyakarta, Indonesia},
  note = {\textbf{awarded best iiWAS/MoMM 2006 workshop paper}},
  pubtype = {workshop}
}
@inproceedings{paper-gi-dissprice-2005,
  author = {Rene Mayrhofer},
  title = {{E}ine {A}rchitektur zur {K}ontextvorhersage},
  booktitle = {{A}usgezeichnete {I}nformatikdissertationen 2004},
  year = {2005},
  volume = {D-5},
  series = {Series of the German Informatics society ({GI})},
  pages = {125--134},
  month = {May},
  publisher = {Lecture Notes in Informatics ({LNI})},
  abstract = {So genannte ``kontextsensitive Systeme'' haben zum Ziel, die eingesetzten
	Computersysteme automatisch an die aktuellen Situationen anzupassen
	und damit bessere Interaktion mit der Umgebung zu erm\"oglichen.
	Diese Arbeit befasst sich mit dem n\"achsten logischen Schritt nach
	der Erkennung des jeweils aktuellen Kontextes, n\"amlich der Vorhersage
	zuk\"unftiger Kontexte. Zu diesem Zweck wurde eine mehrschrittige
	Software-Architektur entwickelt, welche aus den Daten mehrerer einfacher
	Sensoren die aktuellen und zuk\"unftig erwarteten Kontexte gewinnt.
	Die entwickelte Architektur wurde bereits in Form eines flexiblen
	Software-Frameworks umgesetzt und mit aufgezeichneten Daten aus allt\"aglichen
	Situationen evaluiert. Diese Betrachtung zeigt, dass die Vorhersage
	abstrakter Kontexte in Grenzen bereits m\"oglich ist, jedoch noch
	Raum f\"ur Verbesserungen der Vorhersagequalit\"at in zuk\"unftigen
	Arbeiten offen bleibt.},
  day = {2},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/GI-DissPreis2005-Kurzfassung.pdf},
  isbn = {3-88579-409-8},
  pubtype = {other-refereed}
}
@inproceedings{paper-symposium-internet-recht,
  author = {Rene Mayrhofer},
  title = {Technische {H}intergr\"unde f\"ur das rechtliche {H}andeln im {I}nternet},
  booktitle = {{A}ktuelles zum {I}nternet-{R}echt},
  year = {2005},
  pages = {1--16},
  month = {December},
  publisher = {proLibris.at},
  abstract = {Internet-Recht bewegt sich grunds\"atzlich an der Schnittstelle zwischen
	Gesetzgebung und Technik. Wie an vielen Schnittstellen gibt es auch
	hier Schwierigkeiten zu \"uberwinden, und zwar nicht nur in der Findung
	gemeinsamer Ziele, Arbeitsgruppen und schlussendlich L\"osungen,
	sondern vor allem im gegenseitigen Verst\"andnis der den jeweils
	anderen Bereich betreffenden Probleme. Dieser Beitrag soll die technischen
	Hintergr\"unde einiger aktueller Themen an dieser Schnittstelle allgemein
	verst\"andlich n\"aher bringen. Die Auswahl an Themen, welche aus
	technischer Sicht einer Kl\"arung durch die Gesetzgebung bed\"urfen
	bzw. derer, die durch neue Gesetze die Entwicklung neuer technischer
	Systeme erfordern, ist derzeit kaum mehr \"uberschaubar und w\"achst
	weiter. Daher erfolgt in diesem Beitrag eine Konzentration auf die
	technischen Grundlagen f\"ur viele dieser Themen sowie auf eine kleine
	Auswahl von Themen, die von allgemeinem, auch \"offentlichem bzw.
	gesellschaftlichem Interesse sind. Konkret werden die folgenden Themen
	angesprochen: Grundlagen der Kryptographie, Sichere Signatur, Digitales
	Rechte Management (DRM) und Peer-to-Peer Systeme.
	
	Diese Themen stellen eine subjektive Auswahl dar, sollten jedoch die
	derzeit am st\"arksten – auch durch die Tagespresse – diskutierten
	Gebiete abdecken. Der Beitrag ist auf Leser ohne technisches Detailwissen
	ausgerichtet, Erfahrung im Um- gang mit Computersystemen, also zum
	Beispiel mit Webbrowsern und Emailprogrammen, wird jedoch angenommen.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Symposium-Internet-Recht-2005_Grundlagen.pdf},
  eventurl = {http://www.vwrecht.jku.at/Mitarbeiter/mayrhofer/Internet-Recht-Symposium.pdf},
  isbn = {3-902460-20-2},
  location = {Linz, Austria},
  pubtype = {other-refereed}
}
@inproceedings{paper-emcsr2002,
  author = {Rene Mayrhofer and Michael Affenzeller and Herbert Pr\"ahofer and
	Gerhard H\"ofer and Alexander Fried},
  title = {{DEVS} Simulation of Spiking Neural Networks},
  booktitle = {Cybernetics and Systems: Proc. {EMCSR} 2002: 16th European Meeting
	on Cybernetics and Systems Research},
  year = {2002},
  editor = {Robert Trappl},
  volume = {2},
  pages = {573--578},
  month = {April},
  publisher = {Austrian Society for Cybernetic Studies},
  abstract = {This paper presents a new model for simulating Spiking Neural Networks
	using discrete event simulation which might possibly offer advantages
	concerning simulation speed and scalability. Spiking Neural Networks
	are considered as a new computation paradigm, representing an enhancement
	of Artificial Neural Networks by offering more flexibility and degree
	of freedom for modeling computational elements. Although this type
	of Neural Networks is rather new and there is not very much known
	about its features, it is clearly more powerful than its predecessor,
	being able to simulate Artificial Neural Networks in real time but
	also offering new computational elements that were not available
	previously. Unfortunately, the simulation of Spiking Neural Networks
	currently involves the use of continuous simulation techniques which
	do not scale easily to large networks with many neurons. Within the
	scope of the present paper, we discuss a new model for Spiking Neural
	Networks, which allows the use of discrete event simulation techniques,
	possibly offering enormous advantages in terms of simulation flexibility
	and scalability without restricting the qualitative computational
	power.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/emcsr2002spike.ps},
  eventurl = {http://www.osgk.ac.at/emcsr/02/},
  location = {Vienna},
  pubtype = {conference}
}
@inproceedings{paper-pervasive2007,
  author = {Rene Mayrhofer and Hans Gellersen},
  title = {Shake well before use: Authentication based on Accelerometer Data},
  booktitle = {Proc. {Pervasive 2007}: 5th International Conference on Pervasive
	Computing},
  year = {2007},
  volume = {4480},
  series = {LNCS},
  pages = {144--161},
  month = {May},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  abstract = {Small, mobile devices without user interfaces, such as Bluetooth headsets,
	often need to communicate securely over wireless networks. Active
	attacks can only be prevented by authenticating wireless communication,
	which is problematic when devices do not have any a priori information
	about each other. We introduce a new method for device-to-device
	authentication by shaking devices together. This paper describes
	two protocols for combining cryptographic authentication techniques
	with known methods of accelerometer data analysis to the effect of
	generating authenticated, secret keys. The protocols differ in their
	design, one being more conservative from a security point of view,
	while the other allows more dynamic interactions. Three experiments
	are used to optimize and validate our proposed authentication method.},
  day = {13--16},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2007-Shake-Well-Before-Use.pdf},
  eventurl = {http://www.dgp.toronto.edu/conferences/pervasive2007/},
  isbn = {978-3-540-72036-2},
  location = {Toronto, Canada},
  note = {\textbf{awarded best Pervasive 2007 paper}},
  pubtype = {conference},
  short_booktitle = {Proc. {Pervasive 2007}}
}
@inproceedings{paper-ssn2007,
  author = {Rene Mayrhofer and Hans Gellersen},
  title = {On the Security of Ultrasound as Out-of-band Channel},
  booktitle = {Proc. {IPDPS 2007}: 21st {IEEE} International Parallel and Distributed
	Processing Symposium},
  year = {2007},
  pages = {321},
  month = {March},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  note = {Track {SSN 2007}: 3rd International Workshop on Security in Systems
	and Networks},
  abstract = {Ultrasound has been proposed as out-of-band channel for authentication
	of peer devices in wireless ad hoc networks. Ultrasound can implicitly
	contribute to secure communication based on inherent limitations
	in signal propagation, and can additionally be used explicitly by
	peers to measure and verify their relative positions. In this paper
	we analyse potential attacks on an ultrasonic communication channel
	and peer-to-peer ultrasonic sensing, and investigate how potential
	attacks translate to application-level threats for peers seeking
	to establish a secure wireless link. Based on our analysis we propose
	a novel method for authentic communication of short messages over
	an ultrasonic channel.},
  day = {26--30},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/SSN2007-Ultrasound-Security-Analysis.pdf},
  eventurl = {http://www.cse.msu.edu/~lxiao/ssn07},
  isbn = {1-4244-0909-8},
  location = {Long Beach, California, USA},
  pubtype = {workshop}
}
@inproceedings{paper-ubicomp2007-demo,
  author = {Rene Mayrhofer and Hans Gellersen},
  title = {Shake well before use: two implementations for implicit context authentication},
  booktitle = {Adjunct Proc. {Ubicomp 2007}},
  year = {2007},
  pages = {72--75},
  month = {September},
  abstract = {Secure device pairing is especially difficult for spontaneous interaction
	in ubiquitous computing environments because of wireless communication,
	lack of powerful user interfaces, and scalability issues. We demonstrate
	a method to address this problem for small, mobile devices that does
	not require explicit user interfaces like displays or key pads. By
	shaking devices together in one hand for a few seconds, they are
	securely paired. Device authentication happens implicitly as part
	of the pairing process without the need for explicit user interaction
	“just for security”. Our method has been implemented in two variants:
	first, for high-quality data collection using wired accelerometers;
	second, using built-in accelerometers in standard Nokia 5500 mobile
	phones.},
  day = {16--19},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Ubicomp2007-Demo-Shake-Well-Before-Use.pdf},
  eventurl = {http://www.ubicomp2007.org/},
  isbn = {978-3-00-022600-7},
  location = {Innsbruck, AT},
  pubtype = {conference}
}
@inproceedings{paper-ubicomp2007,
  author = {Rene Mayrhofer and Hans Gellersen and Mike Hazas},
  title = {Security by Spatial Reference: Using Relative Positioning to Authenticate
	Devices for Spontaneous Interaction},
  booktitle = {Proc. {Ubicomp 2007}: 9th International Conference on Ubiquitous
	Computing},
  year = {2007},
  volume = {4717},
  series = {LNCS},
  pages = {199--216},
  month = {September},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  abstract = {Spontaneous interaction is a desirable characteristic associated with
	mobile and ubiquitous computing. The aim is to enable users to connect
	their personal devices with devices encountered in their environment
	in order to take advantage of interaction opportunities in accordance
	with their situation. However, it is difficult to secure spontaneous
	interaction as this requires authentication of the encountered device,
	in the absence of any prior knowledge of the device. In this paper
	we present a method for establishing and securing spontaneous interactions
	on the basis of \emph{spatial references} that capture the spatial
	relationship of the involved devices. Spatial references are obtained
	by accurate sensing of relative device positions, presented to the
	user for initiation of interactions, and used in a peer authentication
	protocol that exploits a novel mechanism for message transfer over
	ultrasound to ensures spatial authenticity of the sender.},
  day = {16--19},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Ubicomp2007-Security-by-Spatial-Reference.pdf},
  eventurl = {http://www.ubicomp2007.org/},
  isbn = {978-3-540-74852-6},
  location = {Innsbruck, AT},
  pubtype = {conference},
  short_booktitle = {Proc. {Ubicomp 2007}}
}
@inproceedings{paper-eurocast2011-friendsradar,
  author = {Rene Mayrhofer and Clemens Holzmann},
  title = {\emph{Friends Radar}: Towards a Private {P2P} Location Sharing Platform},
  booktitle = {Proc. {EUROCAST 2011}: 13th International Conference on Computer
	Aided Systems Theory, Part II},
  year = {2011},
  volume = {6928},
  series = {LNCS},
  pages = {528--536},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  day = {6--11},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/EUROCAST2011-FriendsRadar.pdf},
  editors = {Alexis Quesada-Arencibia and José Carlos Rodríguez and Roberto Moreno-Díaz
	jr. and Roberto Moreno-Díaz},
  eventurl = {http://www.fh-hagenberg.at/mcpt2011},
  location = {Las Palmas, Gran Canaria},
  pubtype = {conference}
}
@inproceedings{paper-iwssi2012,
  author = {Rene Mayrhofer and Thomas Kaiser},
  title = {Towards usable authentication on mobile phones: An evaluation of
	speaker and face recognition on off-the-shelf handsets},
  booktitle = {Proc. {IWSSI/SPMU 2012}: 4th International Workshop on Security and
	Privacy in Spontaneous Interaction and Mobile Phone Use, colocated
	with {Pervasive 2012}},
  year = {2012},
  month = {June},
  note = {available online at \url{http://www.medien.ifi.lmu.de/iwssi2011/}},
  abstract = {Authenticating users on mobile devices is particularly challenging
	because of usability concerns: authentication must be quick and as
	unobtrusive as possible. Therefore, biometric methods seem well suited
	for mobile phones. We evaluate both speaker and face recognition
	methods on off-the-shelf mobile devices concerning their accuracy,
	suitability for dealing with low-quality recordings, and running
	with limited resources. Our results show that speaker and face recognition
	can realistically be used on mobile phones, but that improvements
	-- e.g.\ in the form of combining multiple methods -- are still necessary
	and subject to future work.},
  booktitle_short = {Proc. {IWSSI/SPMU 2012}},
  day = {18},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/IWSSI2012-Speaker-and-Face-Recognition.pdf},
  eventurl = {http://www.medien.ifi.lmu.de/iwssi2012/},
  location = {Newcastle, UK},
  pubtype = {workshop}
}
@inproceedings{paper-secco2003,
  author = {Rene Mayrhofer and Florian Ortner and Alois Ferscha and Manfred Hechinger},
  title = {Securing Passive Objects in Mobile Ad-Hoc Peer-to-Peer Networks},
  booktitle = {Electronic Notes in Theoretical Computer Science},
  year = {2003},
  editor = {R. Focardi and G. Zavattaro},
  volume = {85.3},
  month = {June},
  publisher = {Elsevier Science},
  abstract = {Security and privacy in mobile ad-hoc peer-to-peer environments are
	hard to attain, especially when working with passive objects without
	own processing power. We introduce a method for integrating such
	objects into a peer-to-peer environment without infrastructure components
	while providing a high level of privacy and security for peers interacting
	with objects. The integration is done by equipping passive objects
	with public keys, which can be used by peers to validate proxies
	acting on behalf of the objects. To overcome the problem of limited
	storage capacity on small embedded objects, ECC keys are used.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/SecCo2003-Securing-Passive-Objects.pdf},
  eventurl = {http://www.cs.unibo.it/secco03/},
  howpublished = {Available at http://www1.elsevier.com/gej-ng/31/29/23/138/23/show/Products/notes/index.htt},
  issn = {1571-0661},
  location = {Eindhoven},
  pubtype = {workshop}
}
@inproceedings{paper-momm2003,
  author = {Rene Mayrhofer and Harald Radi and Alois Ferscha},
  title = {Recognizing and Predicting Context by Learning from User Behavior},
  booktitle = {Proc. {MoMM 2003}: 1st International Conference On Advances in Mobile
	Multimedia},
  year = {2003},
  editor = {G. Kotsis, A. Ferscha, W. Schreiner and K. Ibrahim},
  volume = {171},
  pages = {25--35},
  month = {September},
  publisher = {Austrian Computer Society ({OCG})},
  abstract = {Current mobile devices like mobile phones or personal digital assistants
	have become more and more powerful; they already offer features that
	only few users are able to exploit to their whole extent. With a
	number of upcoming mobile multimedia applications, ease of use becomes
	one of the most important aspects. One way to improve usability is
	to make devices aware of the user's context, allowing them to adapt
	to the user instead of forcing the user to adapt to the device. Our
	work is taking this approach one step further by not only reacting
	to the current context, but also predicting future context, hence
	making the devices proactive. Mobile devices are generally suited
	well for this task because they are typically close to the user even
	when not actively in use. This allows such devices to monitor the
	user context and act accordingly, like automatically muting ring
	or signal tones when the user is in a meeting or selecting audio,
	video or text communication depending on the user's current occupation.
	This paper presents an architecture that allows mobile devices to
	continuously recognize current and anticipate future user context.
	The major challenges are that context recognition and prediction
	should be embedded in mobile devices with limited resources, that
	learning and adaption should happen on-line without explicit training
	phases and that user intervention should be kept to a minimum with
	non-obtrusive user interaction. To accomplish this, the presented
	architecture consists of four major parts: feature extraction, classification,
	labeling and prediction. The available sensors provide a multi-dimensional,
	highly heterogeneous input vector as input to the classification
	step, realized by data clustering. Labeling associates recognized
	context classes with meaningful names specified by the user, and
	prediction allows to forecast future user context for proactive behavior.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MOMM2003-Recognizing-and-Predicting-Context.pdf},
  eventurl = {http://www.tk.uni-linz.ac.at/momm/},
  isbn = {3-85403-171-8},
  location = {Jakarta, Indonesia},
  long_note = {An extended version appeared as R. Mayrhofer, H. Radi and A. Ferscha:
	Recognizing and Predicting Context by Learning from User %Behavior,
	Radiomatics - Journal of Communication Engineering, ISSN: 1693-5152,
	January 2004},
  pubtype = {conference},
  url = {http://radiomatics.ee.itb.ac.id/issues/vol1/may2004/rene.htm}
}
@incollection{paper-pervasive2004-workshop-dataformat,
  author = {Rene Mayrhofer and Harald Radi and Alois Ferscha},
  title = {A Context Prediction Code and Data Base},
  booktitle = {Proceedings of the Benchmarks and a Database for Context Recognition
	Workshop},
  publisher = {ETH Zurich},
  year = {2004},
  editor = {H. Junker and P. Lukowicz and J. M\"antyjarvi},
  pages = {20--26},
  month = {April},
  note = {part of the Second International Conference on Pervasive Computing
	({PERVASIVE 2004})},
  abstract = {Many of the currently available sensors do not provide simple, numerical
	values but more complex data like a list of other devices in range.
	Although these sensors can, in the general case, not be transformed
	to numerical values, they nonetheless provide valuable information
	about the device or user context. For exploiting all available context
	information, it is thus important to also regard ordinal and nominal
	sensor values. In this paper, we propose to jointly develop a meta
	data format for the evaluation and assessment of context recognition
	and prediction methods.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2004-Workshop-Context-Database.pdf},
  eventurl = {http://www.pervasive2004.org/program_w5.php},
  isbn = {3-9522686-2-3},
  pubtype = {workshop}
}
@inproceedings{paper-mwcn2003,
  author = {Rene Mayrhofer and Harald Radi and Alois Ferscha},
  title = {Feature Extraction in Wireless Personal and Local Area Networks},
  booktitle = {Proc. {MWCN 2003}: 5th International Conference on Mobile and Wireless
	Communications Networks},
  year = {2003},
  pages = {195--198},
  month = {October},
  publisher = {World Scientific},
  abstract = {Context awareness is currently being investigated for applications
	in different areas, including Mobile Computing. Many mobile devices
	are already shipped with support for Bluetooth and Wireless LAN,
	making these technologies commonly available. It is thus possible
	to exploit the wireless interfaces as sensors for deriving information
	about the device/user context. However, extracting features from
	typical Bluetooth or Wireless LAN properties is difficult because
	not only numerical, but also non-numerical features like the list
	of MAC addresses in range are important for context awareness. In
	this paper, we introduce a method to automatically classify these
	highly heterogeneous features with supervised or un-supervised classification
	methods. By defining two operators, a distance metric and an adaption
	operator, any feature can be used as input for the classifier and
	can thus contribute to context detection.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MWCN2003-Heterogeneous-Features.pdf},
  eventurl = {http://www.i2r.a-star.edu.sg/events/call-for-papers/mwcn2003/},
  isbn = {981-238-686-6},
  location = {Singapore},
  long_editor = {Khaldoun Al Agha and Cambyse Guy Omidyar},
  pubtype = {conference}
}
@inproceedings{paper-iiwas2010,
  author = {Rene Mayrhofer and Alexander Sommer and Sinan Saral},
  title = {{Air-Writing}: A Platform for Scalable, Privacy-Preserving, Spatial
	Group Messaging},
  booktitle = {Proc. {iiWAS2010}: 12th International Conference on Information Integration
	and Web-based Applications \& Services},
  year = {2010},
  pages = {181--189},
  month = {November},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  abstract = {Spatial messaging is a direct extension to text and other multi-media
	messaging services that have become highly popular with the current
	pervasiveness of mobile communication. It offers benefits especially
	to mobile computing, providing localised and therefore potentially
	more appropriate delivery of nearly arbitrary content. Location is
	one of the most interesting attributes that can be added to messages
	in current applications, including gaming, social networking, or
	advertising services. However, location is also highly critical in
	terms of privacy. If a spatial messaging platform could collect the
	location traces of all its users, detailed profiling would be possible
	-- and, considering commercial value of such profiles, likely. In
	this paper, we present \emph{Air-Writing}, an approach to spatial
	messaging that fully preserves user privacy while offering global
	scalability, different client interface options, and flexibility
	in terms of application areas. We contribute both an architecture
	and a specific implementation of an attribute based messaging platform
	with special support for spatial messaging and rich clients for J2ME,
	Google Android, and Apple iPhone. The centralised client/server approach
	utilises groups for anonymous message retrieval and client caching
	and filtering as well as randomised queries for obscuring traces.
	An initial user study with 20 users shows that the overall concept
	is easily understandable and that it seems useful to end-users. An
	analysis of real-world and simulated location traces shows that user
	privacy can be ensured, but with a trade-off between privacy protection
	and consumed network resources.},
  booktitle_short = {Proc. {iiWAS2010}},
  day = {8--10},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/iiWAS2010-AirWriting.pdf},
  eventurl = {http://www.iiwas.org/conferences/iiwas2010/},
  isbn = {978-1-4503-0421-4},
  owner = {rene},
  pubtype = {conference},
  timestamp = {2010.09.16}
}
@inproceedings{paper-wais2007,
  author = {Rene Mayrhofer and Martyn Welch},
  title = {A Human-Verifiable Authentication Protocol Using Visible Laser Light},
  booktitle = {Proc. {ARES 2007}: 2nd International Conference on Availability,
	Reliability and Security},
  year = {2007},
  pages = {1143--1147},
  month = {April},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  abstract = {Securing wireless channels necessitates authenticating communication
	partners. For spontaneous interaction, authentication must be efficient
	and intuitive. One approach to create interaction and authentication
	methods that scale to using hundreds of services throughout the day
	is to rely on personal, trusted, mobile devices to interact with
	the environment. Authenticating the resulting device-to-device interactions
	requires an out-of-band channel that is verifiable by the user. We
	present a protocol for creating such an out-of-band channel with
	visible laser light that is secure against man-in-the-middle attacks
	even when the laser transmission is not confidential. A prototype
	implementation shows that an appropriate laser channel can be constructed
	with simple off-the-shelf components.},
  day = {10--13},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/WAIS2007-Laser-Authentication.pdf},
  eventurl = {http://www.csc.lsu.edu/~durresi/wais2007/index.html},
  isbn = {0-7695-2775-2},
  location = {Vienna, Austria},
  long_note = {Track {WAIS 2007}: 1st International Workshop on Advances in Information
	Security},
  pubtype = {workshop},
  short_booktitle = {Proc. {ARES 2007}}
}
@inproceedings{paper-eurocast2009,
  author = {Rene Mayrhofer and Stephan Winkler and Helmut Hlavacs and Michael
	Affenzeller and Stefan Schneider},
  title = {On Structural Identification of 2D Regression Functions for In-door
	Bluetooth Localization},
  booktitle = {Proc. {EUROCAST} 2009},
  year = {2009},
  volume = {5717},
  series = {LNCS},
  pages = {801--808},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/EUROCAST2009-Genetic-Algorithms-for-Bluetooth-Localization.pdf},
  location = {Las Palmas, Gran Canaria},
  pubtype = {conference}
}
@inproceedings{paper-momm2013-gait-recognition,
  author = {Muhammad Muaaz and Rene Mayrhofer},
  title = {An Analysis Of Different Approaches To Gait Recognition Using Cell
	Phone Based Accelerometer},
  booktitle_short = {Proc. {MoMM} 2013},
  year = {2013},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  booktitle = {Proc. {MoMM} 2013: 11th International Conference on Advances in Mobile
	Computing and Multimedia},
  pages = {293--300},
  day = {2--4},
  eventurl = {http://iiwas.org/conferences/momm2013/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2013-Gait-Recognition.pdf},
  location = {Vienna, AT},
  pubtype = {conference}
}
@inproceedings{paper-momm2008,
  author = {Harald Radi and Rene Mayrhofer},
  title = {Towards Alternative User Interfaces for Capturing and Managing Tasks
	with Mobile Devices},
  booktitle = {Proc. {MoMM} 2008: 6th International Conference on Advances in Mobile
	Computing and Multimedia},
  year = {2008},
  pages = {272--275},
  month = {November},
  abstract = {Mobile devices, per definition, are supposed to assist in organizing
	all kinds of things, also tasks of course, because usually such devices
	are always at hands. But due to the very limited and time consuming
	possibilities to interact with such devices many fall back to other
	means to organize their life, like a simple pencil and paper. We
	developed a collaborative task repository that facilitates collaboration
	and teamwork, but on the other hand demands that all tasks have to
	be entered into that system. Therefore a smart and userfriendly interface
	to that repository is mandatory. This work presents concepts on how
	to improve the user interface of mobile devices so that capturing
	tasks on-the-go becomes feasible. We propose to move away from display
	driven user interfaces to more sophisticated interfaces that utilize
	all the sensors and actors of current mobile devices.},
  booktitle_short = {Proc. {MoMM} 2008: 6th International Conference on Advances in Mobile
	Computing and Multimedia},
  day = {24--26},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2008-Towards-Mobile-Task-Management.pdf},
  eventurl = {http://www.iiwas.org/conferences/momm2008/},
  pubtype = {conference}
}
@incollection{paper-pervasive2004-workshop-dataset,
  author = {Harald Radi and Rene Mayrhofer and Alois Ferscha},
  title = {A Notebook Sensory Data Set for Context Recognition},
  booktitle = {Proceedings of the Benchmarks and a Database for Context Recognition
	Workshop},
  publisher = {ETH Zurich},
  year = {2004},
  editor = {H. Junker and P. Lukowicz and J. M\"antyjarvi},
  pages = {17--19},
  month = {April},
  note = {part of the Second International Conference on Pervasive Computing
	({PERVASIVE 2004})},
  abstract = {For a qualitative and quantitative assessment of context prediction
	and recognition methods, real-world data sets are inevitable. By
	collecting sensor data on a single notebook over a period of a few
	months we got a rather large log file of homogeneous and heterogeneous
	features reflecting the users activities during this time frame.
	In this paper we present which devices were exploited as sensors,
	which information was logged and how this information was stored
	for further processing by classification algorithms.},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/Pervasive2004-Workshop-Context-Dataset.pdf},
  eventurl = {http://www.pervasive2004.org/program_w5.php},
  isbn = {3-9522686-2-3},
  pubtype = {workshop}
}
@inproceedings{paper-momm2013-virtualization,
  author = {Peter Riedl and Phillip Koller and Rene Mayrhofer and Matthias Kranz
	and Andreas M\"oller and Marion Koelle},
  title = {Visualizations and Switching Mechanisms for Security Zones},
  booktitle_short = {Proc. {MoMM} 2013},
  year = {2013},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  booktitle = {Proc. {MoMM} 2013: 11th International Conference on Advances in Mobile
	Computing and Multimedia},
  pages = {278--281},
  day = {2--4},
  eventurl = {http://iiwas.org/conferences/momm2013/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2013-Security-Zones.pdf},
  location = {Vienna, AT},
  pubtype = {conference}
}
@inproceedings{paper-phonecom2012,
  author = {Peter Riedl and Rene Mayrhofer},
  title = {Towards a Practical, Scalable Self-Localization System for {Android}	Phones based on {WLAN} Fingerprinting},
  booktitle = {Proc. {ICDCSW} 2012: 32nd International Conference on Distributed
	Computing Systems Workshops},
  year = {2012},
  pages = {98--101},
  month = {June},
  publisher = {IEEE CS Press},
  address = {Washington, DC, USA},
  abstract = {Indoor localization is becoming increasingly important for mobile
	applications. WLAN fingerprinting is a compelling technique because
	it builds upon existing infrastructure and client hardware available
	in off-the-shelf mobile devices. We evaluate different methods for
	WLAN fingerprint classification with a focus on on-device localization.
	The main scientific contribution of this approach is that any Android
	based device can localize itself (without any server being able to
	determine the current location) using existing WLAN infrastructure
	(no additional access points have to be installed, the firmware of
	existing access points doesn't have to be changed). This approach
	was chosen to make indoor localization feasible in non-academic use
	cases.
	
	 With a functional implementation and a simple procedure for collecting
	WLAN fingerprints, we currently achieve an accuracy of 4\,m in 90\%
	of all cases with a mean error of only 2.2\,m when the same device
	is used for training and testing. Next steps are calibration between
	different mobile devices, post-processing in terms of movement, and
	automatic downloading of the required WLAN fingerprint databases
	on a global scale.},
  booktitle_short = {Proc. {ICDCSW} 2012},
  day = {18},
  doi = {10.1109/ICDCSW.2012.26},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/ICDCSW2012-WLAN-Fingerprinting.pdf},
  location = {Macau, CN},
  pubtype = {conference}
}
@inproceedings{paper-momm2013-javacard-emulator,
  author = {Michael Roland and Josef Langer and Rene Mayrhofer},
  title = {(Ab)using foreign VMs: Running Java Card Applets in non-Java Card
	Virtual Machines},
  booktitle_short = {Proc. {MoMM} 2013},
  year = {2013},
  month = {December},
  publisher = {ACM Press},
  address = {New York, NY, USA},
  booktitle = {Proc. {MoMM} 2013: 11th International Conference on Advances in Mobile
	Computing and Multimedia},
  pages = {286--292},
  day = {2--4},
  eventurl = {http://iiwas.org/conferences/momm2013/},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/MoMM2013-Javacard-Emulator.pdf},
  location = {Vienna, AT},
  pubtype = {conference}
}
@inproceedings{paper-eics2012-tschernuth,
  author = {Michael Tschernuth and Michael Lettner and Rene Mayrhofer},
  title = {Unify localization using user interface description languages and
	a navigation context-aware translation tool},
  booktitle = {Proc. {EICS 2012}: 4th ACM SIGCHI symposium on Engineering interactive
	computing systems},
  year = {2012},
  pages = {179--188},
  month = {June},
  publisher = {ACM},
  abstract = {The past few years have shown a tendency from desktop software development
	towards mobile application development due to the increasing amount
	of smartphone users and available devices. Compared to traditional
	desktop applications, requirements are different in the mobile world.
	Due to the massive amount of mobile applications it is important
	to bring a new idea to the market very quickly and concurrently target
	a large number of users all over the world. The aspect of localization
	is crucial if the product should be usable in different countries.
	The term localization in this context refers to the process of adapting
	a software to different regions by changing the language, image resources,
	reading direction or other regional requirements. The proposed solution
	covers the aspect of string translation, with a focus on devices
	where the screen area is limited. Translating a software poses a
	challenge since the text can have several meanings on the one hand
	and has to match the available screen space on the other hand.
	
	 Knowing the context and area where a string appears in the user interface
	can improve the quality and accuracy of the translation. Besides
	that it reduces efforts for layout implementation and testing. This
	paper refers to that feature as navigation context-aware. A Context-Aware
	Translation Tool (CATT) including this feature is presented. As an
	input for the tool a user interface description language (UIDL) is
	used which contributes platform independence to the tool. To increase
	the applicability of the tool to a number of description languages,
	a meta-model was created which specifies crucial compatibility requirements.
	An evaluation of existing languages regarding their compatibility
	to the proposed model and a discussion of limitations is included.},
  day = {25--28},
  doi = {10.1145/2305484.2305514},
  eventurl = {http://eics-conference.org/2012/},
  isbn = {978-1-4503-1168-7},
  location = {Copenhagen, Denmark},
  pubtype = {conference}
}
@inproceedings{paper-eurocast2011-mda1,
  author = {Michael Tschernuth and Michael Lettner and Rene Mayrhofer},
  title = {Evaluation of Descriptive User Interface Methodologies for Mobile
	Devices},
  booktitle = {Proc. {EUROCAST 2011}: 13th International Conference on Computer
	Aided Systems Theory, Part II},
  year = {2011},
  volume = {6928},
  series = {LNCS},
  pages = {520--527},
  month = {February},
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg, Wien},
  day = {6--11},
  documenturl = {http://www.mayrhofer.eu.org/downloads/publications/EUROCAST2011-MDA-User-Interfaces.pdf},
  editors = {Alexis Quesada-Arencibia and José Carlos Rodríguez and Roberto Moreno-Díaz
	jr. and Roberto Moreno-Díaz},
  eventurl = {http://www.fh-hagenberg.at/mcpt2011},
  location = {Las Palmas, Gran Canaria},
  pubtype = {conference}
}
@inproceedings{paper-ubicomp2015adjunct-cormorant,
  author = {Hintze, Daniel and Findling, Rainhard D. and Muaaz, Muhammad and Koch, Eckhard and Mayrhofer, Ren{\'e}},
  title = {{CORMORANT}: Towards Continuous Risk-aware Multi-modal Cross-device Authentication},
  booktitle = {Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2015 ACM International Symposium on Wearable Computers: Adjunct Publication (UbiComp 2015)},
  series = {UbiComp '15},
  year = {2015},
  isbn = {978-1-4503-3575-1},
  location = {Osaka, Japan},
  pages = {169--172},
  numpages = {4},
  url = {http://doi.acm.org/10.1145/2800835.2800906},
  doi = {10.1145/2800835.2800906},
  acmid = {2800906},
  publisher = {ACM},
  address = {New York, NY, USA},
  keywords = {authentication, biometrics, risk assessment},
  pubtype = {workshop}
}
@inproceedings{paper-momm2015-cormorant,
  abstract = {Mobile devices, ubiquitous in modern lifestyle, embody and provide convenient access to our digital lives. Being small and mobile, they are easily lost or stole, therefore require strong authentication to mitigate the risk of unauthorized access. Common knowledge-based mechanism like PIN or pattern, however, fail to scale with the high frequency but short duration of device interactions and ever increasing number of mobile devices carried simultaneously. To overcome these limitations, we present CORMORANT, an extensible framework for risk-aware multi-modal biometric authentication across multiple mobile devices that offers increased security and requires less user interaction.},
  address = {Brussels, Belgium},
  author = {Daniel Hintze and Muhammad Muaaz and Rainhard Dieter Findling and Sebastian Scholz and Eckhard Koch and René Mayrhofer},
  booktitle = {13th International Conference on Advances in Mobile Computing and Multimedia (MoMM 2015)},
  doi = {10.1145/2837126.2843845},
  isbn = {978-1-4503-3493-8},
  keywords = {biometrics; multi-modal authentication; risk assessment},
  month = {12/2015},
  organization = {ACM},
  pages = {384–388},
  publisher = {ACM},
  title = {Confidence and Risk Estimation Plugins for Multi-Modal Authentication on Mobile Devices using {CORMORANT}},
  year = {2015},
  pubtype = {conference}
}
@inproceedings{paper-eurocast2015-crosspocket-gait,
  title = {Cross Pocket Gait Authentication using Mobile Phone Based Accelerometer Sensor},
  booktitle = {Proc. {EUROCAST} 2015: 15th International Conference on Computer Aided Systems Theory},
  year = {2015},
  month = {Feb.},
  day = {8--13},
  doi = {10.1007/978-3-319-27340-2_90},
  location = {Las Palmas de Gran Canaria, Spain},
  pages = {731--738},
  author = {Muhammad Muaaz and Ren{\'e} Mayrhofer},
  series = {LNCS},
  pubtype = {conference}
}
@inproceedings{paper-mum2015-vibration-patterns,
  title = {Towards Device-to-User Authentication: Protecting Against Phishing Hardware by Ensuring Mobile Device Authenticity using Vibration Patterns},
  booktitle = {Proc. {MUM 2015}: 14th International Conference on Mobile and Ubiquitous Multimedia},
  year = {2015},
  month = {Dec.},
  publisher = {ACM},
  location = {Linz, Austria},
  abstract = {Users usually authenticate to mobile devices before using them (e.g\ PIN, password), but devices do not do the same to users. Revealing the authentication secret to a non-authenticated device potentially enables attackers to obtain the secret, by replacing the device with an identical-looking malicious device. The revealed authentication secret could be transmitted to the attackers immediately, who then conveniently authenticate to the real device. Addressing this attack scenario, we analyze different approaches towards mobile device-to-user (D2U) authentication, for which we provide an overview of advantages/drawbacks, potential risks and device authentication data bandwidth estimations. We further analyze vibration as one D2U feedback channel that is unobtrusive and hard to eavesdrop, including a user study to estimate vibration pattern recognition using a setup of \ bits per second (b/s). Study findings indicate that users are able to distinguish vibration patterns with median correctness of 97.5\% (without taking training effects into account) - which indicates that vibration could act as authentication feedback channel and should be investigated further in future research.},
  keywords = {feedback, mobile authentication, Phishing hardware, vibration},
  author = {Rainhard Dieter Findling and Ren{\'e} Mayrhofer},
  pubtype = {conference}
}
@inproceedings{paper-isc2014-trustedboot,
  title = {A Practical Hardware-Assisted Approach to Customize Trusted Boot for Mobile Devices},
  booktitle = {Information Security Conference (ISC 2014)},
  year = {2014},
  publisher = {Springer International Publishing},
  organization = {Springer International Publishing},
  address = {Hong Kong},
  author = {Javier Gonz{\'a}lez and Michael H{\"o}lzl and Peter Riedl and Philippe Bonnet and Ren{\'e} Mayrhofer},
  pubtype = {conference}
}
@inproceedings{paper-momm2016-gait-gaussian-mixture,
  address = {Singapore},
  author = {Muhammad Muaaz and Ren\'e Mayrhofer},
  booktitle = {Proceedings of the 14th International Conference on Advances in Mobile Computing and Multimedia (MoMM 2016)},
  doi = {10.1145/3007120.3007164},
  keywords = {Accelerometer; gait recognition; Gaussian Mixture Models; segmentation; variance},
  month = {11/2016},
  pages = {288--291},
  publisher = {ACM},
  title = {Accelerometer based Gait Recognition using Adapted Gaussian Mixture Models},
  year = {2016},
  pubtype = {conference}
}
@inproceedings{paper-momm2016-damn,
  address = {Singapore},
  author = {Gerald Schoiber and Ren\'e Mayrhofer and Michael H\"olzl},
  booktitle = {Proceedings of the 14th International Conference on Advances in Mobile Computing and Multimedia (MoMM 2016)},
  doi = {10.1145/3007120.3007161},
  keywords = {Android; Code Analysis; Debugging; Reverse Engineering},
  month = {11/2016},
  organization = {ACM},
  pages = {40--44},
  publisher = {ACM},
  title = {{DAMN} - A Debugging and Manipulation Tool for Android Applications},
  year = {2016},
  pubtype = {conference}
}
@inproceedings{paper-momm2016-eid-physical-offline-verification,
  abstract = {There are many systems that provide users with an electronic identity (eID) to sign documents or authenticate to online services (e.g. governmental eIDs, OpenID). However, current solutions lack in providing proper techniques to use them as regular ID cards that digitally authenticate their holders to another physical person in the real world. We envision a fully mobile eID which provides such functionality in a privacy-preserving manner, fulfills requirements for governmental identities with high security demands (such as driving licenses, or passports) and can be used in the private domain (e.g. as loyalty cards). In this paper, we present potential use cases for such a flexible and privacy-preserving mobile eID and discuss the concept of privacy-preserving attribute queries. Furthermore, we formalize necessary functional, mobile, security, and privacy requirements, and present a brief overview of potential techniques to cover all of them.},
  address = {Singapore},
  author = {Michael H\"olzl and Michael Roland and Ren\'e Mayrhofer},
  booktitle = {Proceedings of the 14th International Conference on Advances in Mobile Computing and Multimedia (MoMM 2016)},
  doi = {10.1145/3007120.3007158},
  keywords = {electronic identities; mobile eID; Privacy; requirements},
  month = {11/2016},
  organization = {ACM},
  pages = {280–283},
  publisher = {ACM},
  title = {Real-World Identification: Towards a Privacy-Aware Mobile {eID} for Physical and Offline Verification},
  year = {2016},
  pubtype = {conference}
}
@inproceedings{paper-momm2016-biometric-match-on-card,
  abstract = {Biometrics have become important for authentication on mobile devices, e.g. to unlock devices before using them. One way to protect biometric information stored on mobile devices from disclosure is using embedded smart cards (SCs) with biometric match-on-card (MOC) approaches. Com- putational restrictions of SCs thereby also limit biometric matching procedures. We present a mobile MOC approach that uses offline training to obtain authentication models with a simplistic internal representation in the final trained state, whereat we adapt features and model representation to enable their usage on SCs. The obtained model is used within SCs on mobile devices without requiring retraining when enrolling individual users. We apply our approach to acceleration based mobile gait authentication, using a 16 bit integer range Java Card, and evaluate authentication performance and computation time on the SC using a pub- licly available dataset. Results indicate that our approach is feasible with an equal error rate of \~{}12\% and a computation time below 2s on the SC, including data transmissions and computations. To the best of our knowledge, this thereby represents the first practically feasible approach towards acceleration based gait match-on-card authentication.},
  address = {Singapore},
  author = {Rainhard Dieter Findling and Michael H\"olzl and Ren\'e Mayrhofer},
  booktitle = {Proceedings of the 14th International Conference on Advances in Mobile Computing and Multimedia (MoMM 2016)},
  doi = {10.1145/3007120.3007132},
  keywords = {Acceleration; authentication; gait; match-on-card; mobile biometrics; smart card},
  month = {11/2016},
  organization = {ACM},
  pages = {250--260},
  publisher = {ACM},
  title = {Mobile Gait Match-on-Card Authentication from Acceleration Data with Offline-Simplified Models},
  year = {2016},
  pubtype = {conference}
}
@inproceedings{paper-momm2016-mobile-authentication-risk-assessment,
  abstract = {Mobile devices offer access to our digital lives and thus need to be protected against the risk of unauthorized physical access by applying strong authentication, which in turn adversely affects usability. The actual risk, however, depends on dynamic factors like day and time. In this paper we discuss the idea of using location-based risk assessment in combination with multi-modal biometrics to adjust the level of authentication necessary to the situational risk of unauthorized access.},
  address = {Heidelberg, Germany},
  author = {Daniel Hintze and Sebastian Scholz and Eckhard Koch and Ren\'e Mayrhofer},
  booktitle = {2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, UbiComp Adjunct 2016, Heidelberg, Germany, September 12-16, 2016},
  doi = {10.1145/2968219.2971448},
  keywords = {authentication; biometrics; risk assessment},
  month = {09/2016},
  organization = {ACM},
  pages = {85--88},
  publisher = {ACM},
  title = {Location-based Risk Assessment for Mobile Authentication},
  year = {2016},
  pubtype = {conference}
}
@inproceedings{asplos,
  author = {Rigger, Manuel and Schatz, Roland and Mayrhofer, Rene and Grimmer, Matthias and M\"{o}ssenb\"{o}ck, Hanspeter},
  title = {Sulong, and Thanks For All the Bugs: Finding Errors in C Programs by Abstracting from the Native Execution Model},
  booktitle = {Proceedings of the Twenty-Third International Conference on Architectural Support for Programming Languages and Operating Systems},
  series = {ASPLOS 2018},
  location = {Williamsburg, VA, USA},
  doi = {10.1145/3173162.3173174},
  isbn = {978-1-4503-4911-6/18/0},
  year = {2018},
  pubtype = {conference}
}