Publikationen VS: Bibliographie 2010 BibTeX
@inproceedings {INPROC-2010-81,
author = {Ralph Lange and Frank D{\"u}rr and Kurt Rothermel},
title = {{Indexing Source Descriptions based on Defined Classes}},
booktitle = {Proceedings of the 14th International Database Engineering and Applications Symposium (IDEAS '10). Montreal, QC, Canada. August 2010},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {245--256},
type = {Konferenz-Beitrag},
month = {August},
year = {2010},
keywords = {heterogeneous information systems; source descriptions; indexing of source descriptions; defined classes; tree-based index structure},
language = {Englisch},
cr-category = {H.2.5 Heterogeneous Databases,
H.3.3 Information Search and Retrieval},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-81/INPROC-2010-81.pdf,
http://doi.acm.org/10.1145/1866480.1866514},
contact = {ralph.lange@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Scaling heterogeneous information systems (HIS) to thousands of sources poses
particular challenges to source discovery. It requires a powerful formalism for
describing the contents of the sources in a concise manner and for formulating
compatible queries as well as a suitable structure for indexing and retrieving
the source descriptions efficiently.
We propose an extended logic-based description formalism for large-scale HIS
with structured sources and a shared ontology. The formalism refines existing
approaches that describe the sources by constraints on the attribute value
ranges in several ways: It allows for complex, nested descriptions based on
defined classes. It supports alternative descriptions to express that a source
may be discovered by different combinations of constraints. Finally, it allows
to adjust between positive matching, similar to keyword-based discovery, and
negative matching, as used in existing logic-based approaches.
We further propose the SDC-Tree for indexing such source descriptions. To allow
for efficient discovery, the SDC-Tree features multidimensional indexing
capabilities for the different attributes and the IS-A hierarchy of the shared
ontology, but also incorporates the existence or absence of constraints. For
this purpose, it supports three different types of node split operations which
exploit the expressiveness of the description formalism. Therefore, we also
propose a generic split algorithm which can be used with arbitrary ontologies.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-81&engl=0}
}
@inproceedings {INPROC-2010-80,
author = {Hannes Wolf and Klaus Herrmann and Kurt Rothermel},
title = {{Robustness in Context-Aware Mobile Computing}},
booktitle = {IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob'2010)},
address = {Niagara Falls, Canada},
publisher = {IEEE Communications Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {46--53},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2010},
doi = {10.1109/WIMOB.2010.5645026},
language = {Englisch},
cr-category = {H.4.1 Office Automation,
I.5.1 Pattern Recognition Models},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-80/INPROC-2010-80.pdf,
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5645026},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {High level context recognition and situation detection are an enabling
technologies for unobtrusive mobile computing systems. Significant progress has
been made in processing and managing context information, leading to
sophisticated frameworks, middlewares, and algorithms. Despite great
improvements, context aware systems still require a significantly increased
recognition accuracy for high-level context information on uncertain sensor
data to enable the robust execution of context-aware applications. Recently
Adaptable Pervasive Workflows (APF)s have been presented as innovative
programming paradigm for mobile context-aware applications. We propose a novel
Flow Context System (FlowCon) that builds upon APFs. FlowCon uses structural
information from the APF to increase accuracy of uncertain high-level context
information up to 49$\backslash$\%. This way we make an important step to enable robust
execution of mobile context-aware applications.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-80&engl=0}
}
@inproceedings {INPROC-2010-78,
author = {A. Bucchiarone and A. Marconi and M. Pistore and S. F{\"o}ll and K. Herrmann and C. Hiesinger and S. Marinovic},
title = {{An Overall Process for Self-Adaptive Pervasive Systems}},
booktitle = {Proceedings of the Second International Conference on Adaptive and Self-adaptive Systems and Applications : ADAPTIVE 2010 ; Lisbon, Portugal, November 21-26, 2010},
publisher = {Elsevier},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--6},
type = {Konferenz-Beitrag},
month = {November},
year = {2010},
language = {Deutsch},
cr-category = {D.2.9 Software Engineering Management,
D.2.11 Software Engineering Software Architectures},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Self-adaptive pervasive systems often implement adaptation in a centralised
manner, where one component holds all the necessary knowledge to identify when
and how the system needs to adapt. In self-adaptive pervasive systems, composed
of autonomous components with different authorities (such as security,
distribution, etc.), this approach cannot be implemented as composing a
centralised knowledge is not feasible and it also obstructs the system's
ability to dynamically change its components. A simple alternative would be to
allow each component to adapt independently but this can quickly give rise to
conflicts, race conditions and oscillations between multiple independent
adaptations. To avoid these problems, we propose to coordinate individual
adaptations so that each component's adaptation goals are satisfied. Each
component proposes an adaptation which is reviewed by other components who may
propose their own adaptations that they may need to do. This continues until a
complete adaptation plan is agreed upon. In cases where certain individual
adaptations conflict with some components' goals, components are instructed to
seek alternative proposals. The Adaptation Manager component is in charge of
the negotiation process and it also has the authority to resolve certain
conflicts between adaptations. Our approach is evaluated in the context of
pervasive workflow systems where the failure probability and execution times
are assessed.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-78&engl=0}
}
@inproceedings {INPROC-2010-71,
author = {Bilal Hameed and Imran Ahmed Khan and Frank D{\"u}rr and Kurt Rothermel},
title = {{An RFID Based Consistency Management Framework for Production Monitoring In a Smart Real-Time Factory}},
booktitle = {Proceedings of 2010 Internet of Things Conference (To Appear).},
address = {Tokyo, Japan},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--8},
type = {Konferenz-Beitrag},
month = {November},
year = {2010},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks,
C.2.1 Network Architecture and Design},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The use of RFID devices for real-time production monitoring in modern factories
is impeded by the inherent unreliability of RFID devices. In this paper we
present a consistency stack that conceptually divides the different consistency
issues in production monitoring into separate layers. In addition to this we
have built a consistency management framework to ensure consistent real-time
production monitoring, using unreliable RFID devices. In detail, we deal with
the problem of detecting object sequences by a set of unreliable RFID readers
that are installed along production lines. We propose a probabilistic sequence
detection algorithm that assigns probabilities to objects detected by RFID
devices and provides probabilistic guarantees regarding the real-time sequences
of objects on the production lines.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-71&engl=0}
}
@inproceedings {INPROC-2010-69,
author = {Andreas Benzing and Boris Koldehofe and Marco V{\"o}lz and Kurt Rothermel},
title = {{Multilevel Predictions for the Aggregation of Data in Global Sensor Networks}},
booktitle = {Proceedings of the 14th IEEE/ACM International Symposium on Distributed Simulation and Real Time Applications},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {169--178},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2010},
keywords = {Global Sensor Networks; Distributed Stream Processing; Predictors},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-69/INPROC-2010-69.pdf,
http://ieeexplore.ieee.org/search/srchabstract.jsp?tp=&arnumber=5636734},
contact = {andreas.benzing@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Real-time simulations are one challenging application domain that is expected
to introduce high requirements to global sensor applications. Besides having
hard constraints on latency bounds at which data needs to be processed,
simulation applications will impose high requirements with respect to available
bandwidth. Predictors, originally introduced in the domain of wireless sensor
networks for energy saving, are one appealing solution to provide real-time
estimates and at the same time significantly reduce the data rates. While in
the setting of wireless sensor networks many prediction models have been
analyzed, their behavior and use is unclear when applied to distributed data
streams where aggregation results are typically processed over multilevel
hierarchies.
In the context of weather simulations, we propose a distributed R-Tree-based
aggregation algorithm that allows for efficient reuse of aggregate queries. In
the setting of real temperature readings taken from weather stations during one
month, we study the trade-off between updates of the prediction model and the
precision of the predicted values. Our evaluations indicate that even in
situations where complex prediction models are expected to perform best, simple
prediction models give higher benefits with respect to saving bandwidth while
providing similar data accuracy.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-69&engl=0}
}
@inproceedings {INPROC-2010-65,
author = {Daniel Fischer and Klaus Herrmann and Kurt Rothermel},
title = {{GeSoMo - A General Social Mobility Model for Delay Tolerant Networks}},
booktitle = {Proceedings of the 7th IEEE International Conference on Mobile Ad-hoc and Sensor Systems (MASS '10)},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--9},
type = {Konferenz-Beitrag},
month = {November},
year = {2010},
language = {Deutsch},
cr-category = {C.2.1 Network Architecture and Design,
C.4 Performance of Systems,
I.6.0 Simulation and Modeling General},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Simulation is a fundamental means for evaluating mobile applications based on
ad-hoc networks. This has led to the design of a large number of mobility
models for simulating realistic user movement under physical constraints
(obstacles, acceleration, inertia etc.). In recent years, the new breed of
social mobility models (SMMs) has risen. These SMMs model the $\backslash$emph{social
aspects of human mobility}, i.e. which users meet, when and how often. Such
information is indispensable for the simulation of a wide range of
socially-aware communication protocols mostly based on delay-tolerant networks,
including opportunistic ad-hoc routing and data dissemination systems. Each SMM
needs a model of the relations between a set of relevant people (called social
network model -- SNM) in order to simulate their mobility. Existing SMMs lack
flexibility since each of them is implicitly restricted to a specific,
simplifying SNM.
We present GeSoMo, a new SMM that separates the core mobility model from the
structural description of the social network underlying the simulation. This
simple and elegant design principle gives GeSoMo generalizing power: Arbitrary
existing and future SNMs can be used without changing GeSoMo itself. Our
evaluation results show that GeSoMo produces simulations that are coherent with
a broad range of empirical data describing real-world human social behavior and
mobility.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-65&engl=0}
}
@inproceedings {INPROC-2010-63,
author = {Harald Weinschrott and Frank D{\"u}rr and Kurt Rothermel},
title = {{StreamShaper: Coordination Algorithms for Participatory Mobile Urban Sensing}},
booktitle = {Proceedings of the 7th IEEE International Conference on Mobile Ad-hoc and Sensor Systems (MASS'10)},
address = {San Francisco, CA, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--10},
type = {Konferenz-Beitrag},
month = {November},
year = {2010},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-63/INPROC-2010-63.pdf,
http://www.comnsense.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In this paper we introduce mechanisms for automated mapping of urban areas that
provide a virtual sensor abstraction to the applications. We envision a
participatory system that exploits widely available devices as mobile phones to
cooperatively read environmental conditions as air quality or noise pollution,
and map these measurements to stationary virtual sensors. We propose spatial
and temporal coverage metrics for measuring the quality of acquired sensor data
that reflect the conditions of urban areas and the uncontrolled movement of
nodes. To achieve quality requirements and efficiency in terms of energy
consumption, this paper presents two algorithms for coordinating sensing. The
first is based on a central control instance, which assigns sensing tasks to
mobile nodes based on movement predictions. The second algorithm is based on
coordination of mobile nodes in an ad-hoc network. By extensive simulations, we
show that these algorithms achieve a high quality of readings, which is about
95\% of the maximum possible. Moreover, the algorithms achieve a very high
energy efficiency allowing for drastic savings compared to uncoordinated
sensing.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-63&engl=0}
}
@inproceedings {INPROC-2010-60,
author = {Faraz Memon and Frank D{\"u}rr and Kurt Rothermel},
title = {{Index Recommendation Tool for Optimized Information Discovery Over Distributed Hash Tables}},
booktitle = {Proceedings of the 35th International Conference on Local Computer Networks (LCN '10)},
address = {Dever, CO, USA},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--8},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2010},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
E.1 Data Structures,
E.2 Data Storage Representations,
H.3.1 Content Analysis and Indexing},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-60/INPROC-2010-60.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Peer-to-peer (P2P) networks allow for efficient information discovery in
large-scale distributed systems. Although point queries are well supported by
current P2P systems -- in particular systems based on distributed hash tables
(DHTs) --, providing efficient support for more complex queries remains a
challenge. Our research focuses on the efficient support for multi-attribute
range (MAR) queries over DHT-based information discovery systems.
Traditionally, the support for MAR queries over DHTs has been provided either
by creating an individual index for each data attribute or by creating a single
index using the combination of all data attributes. In contrast to these
approaches, we propose to create a set of indices over selected attribute
combinations. In order to limit the overhead induced by index maintenance, the
total number of created indices has to be limited. Thus, the resulting problem
is to create a limited number of indices such that the overall system
performance is optimal for MAR queries. In this paper, we propose an index
recommendation tool that implements heuristic solutions to this NP-hard
problem. Our evaluations show that these heuristics lead to a close-to-optimal
system performance for MAR queries.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-60&engl=0}
}
@inproceedings {INPROC-2010-57,
author = {Stamatia Rizou and Frank D{\"u}rr and Kurt Rothermel},
title = {{Providing QoS Guarantees for Large-Scale Operator Networks}},
booktitle = {Proceedings of the 12th IEEE International Conference on High Performance Computing and Communications},
address = {Melbourne, VIC, Australia},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {337--345},
type = {Konferenz-Beitrag},
month = {September},
year = {2010},
doi = {10.1109/HPCC.2010.53},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-57/INPROC-2010-57.pdf,
http://dx.doi.org/10.1109/HPCC.2010.53},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Application areas like global sensor networks and data stream processing
involve the on-line processing of large amounts of data in an overlay network
of operators on top of the Internet infrastructure. Trying to fulfill QoS
guarantees in such networks is a challenging task that should be realized under
the requirement for optimal usage of common resources in the network. Therefore
in this paper, we formalize a constrained optimization problem for the
placement of operators in an overlay network which strives for satisfying user
QoS constraints subject to latency, while minimizing the network load induced
by the deployment of the operators in the network. Since the initial problem is
NP-hard, we solve at a first step the problem in an intermediate continuous
latency space and then we map the continuous solution to its discrete variant.
Our evaluations provide an analysis about the inherent interdepedence between
the two metrics, network usage and latency, subject to this paper and
furthermore shows that our algorithm achieves a good balance between the user
requirements and the usage of the network resources.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-57&engl=0}
}
@inproceedings {INPROC-2010-56,
author = {Stamatia Rizou and Frank D{\"u}rr and Kurt Rothermel},
title = {{Solving the Multi-operator Placement Problem in Large-Scale Operator Networks}},
booktitle = {Proceedings of the 19th International Conference on Computer Communication Networks},
address = {Zurich, Switzerland},
publisher = {IEEE Communications Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--6},
type = {Konferenz-Beitrag},
month = {August},
year = {2010},
doi = {10.1109/ICCCN.2010.5560127},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-56/INPROC-2010-56.pdf,
http://dx.doi.org/10.1109/ICCCN.2010.5560127},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Processing streams of data in an overlay network of operators distributed over
a wide-area network is a common idea shared by different applications such as
distributed event correlation systems and large-scale sensor networks. In order
to utilize network resources efficiently and allow for the parallel deployment
of a large number of large-scale operator networks, suitable placement
algorithms are vital that place operators on physical nodes. In this paper, we
present a distributed placement algorithm that minimizes the bandwidth-delay
product of data streams between operators of the network in order to reduce the
induced network load. Since the fundamental optimization problem is NP-hard, we
propose a heuristic solution. First, we calculate an optimal solution in an
intermediate continuous search space, called latency space. Subsequently the
continuous solution is mapped to the physical network. Our evaluations show
that this algorithm reduces the resulting network load significantly compared
to state of the art algorithms and achieves results close to the optimum.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-56&engl=0}
}
@inproceedings {INPROC-2010-46,
author = {Stefan F{\"o}ll and Klaus Herrmann and Christian Hiesinger},
title = {{Flow-Based Context Prediction}},
booktitle = {Proceedings of the 7th International Conference on Pervasive Services (ICPS 2010), Berlin, Germany, July 13-15, 2010},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--1},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
keywords = {Context prediction, Markov model, workflows, context awareness, probabilistic user behaviour},
language = {Englisch},
cr-category = {G.3 Probability and Statistics,
I.2.6 Artificial Intelligence Learning},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-46/INPROC-2010-46.pdf},
contact = {stefan.foell@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Context prediction has been recognized as an enabler for proactive pervasive
services that anticipate future situations already ahead of time. Traditional
context predictors are limited by their agnostic view on the targeted
application domain when analysing context histories of past user behaviour.
Awareness about the processes in which an entity is involved can provide rich
information to foresee future context changes more accurately. We present an
approach for context prediction in pervasive environments that are
characterized by context-aware workflows. In order to benefit from the explicit
knowledge about human behaviour in these environments, we devise a context
predictor that learns the relationship of context changes with the flow of
activities performed by humans. This relationship is encoded as a probabilistic
state transition system that can be explored to determine the most likely paths
of future context occurrences. Our evaluation shows that our enhanced predictor
is able to extract patterns from context histories that are inaccessible to
history-only predictors and significantly improves the prediction accuracy.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-46&engl=0}
}
@inproceedings {INPROC-2010-43,
author = {Stamatia Rizou and Kai H{\"a}ussermann and Frank D{\"u}rr and Nazario Cipriani and Kurt Rothermel},
title = {{A system for distributed context reasoning.}},
booktitle = {Proceedings of ICAS’10: International Conference on Autonomous and Autonomic Systems},
publisher = {IEEE Computer Society Conference Publishing Services},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {84--89},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2010},
isbn = {978-0-7695-3970-6},
doi = {10.1109/ICAS.2010.21},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-43/INPROC-2010-43.pdf,
http://dx.doi.org/10.1109/ICAS.2010.21},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {Context aware systems use context information to adapt their behaviour
accordingly. In order to derive high level context information from low level
context, such as sensor values, context reasoning methods that correlate
observable context information, are necessary. Several context reasoning
mechanisms have been proposed in the literature. Usually these mechanisms are
centralized, leading to suboptimal utilization of network resources and poor
system performance in case of large-scale scenarios. Therefore to increase the
scalability of context reasoning systems the development of methods that
distribute the reasoning process is necessary. Existing distributed approaches
are method specific and do not provide a generic formalization for distributed
reasoning. In this paper we introduce a novel system which enables distributed
context reasoning in a generic way that is independent of the reasoning
algorithm.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-43&engl=0}
}
@inproceedings {INPROC-2010-38,
author = {Gerald G. Koch and M. Adnan Tariq and Boris Koldehofe and Kurt Rothermel},
title = {{Event processing for large-scale distributed games}},
booktitle = {Proceedings of the 4th International Conference on Distributed Event-Based Systems (DEBS'10)},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {103--104},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
doi = {http://doi.acm.org/10.1145/1827418.1827440},
isbn = {978-1-60558-927-5},
keywords = {Cordies; SpoVNet; CEP},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-38/INPROC-2010-38.pdf,
http://doi.acm.org/10.1145/1827418.1827440},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Novel peer-to-peer-based multiplayer online games are instantiated in an ad-hoc
manner without the support of dedicated infrastructure and maintain their state
in a distributed manner. Although their employed communication paradigms
provide efficient access to sections of distributed state, such communication
fails if the participants need to access large subsets of the application state
in order to detect high-level situations. We propose a demonstration that shows
how multiplayer online games can benefit from using publish/subscribe
communication and complex event processing alongside their traditional
communication paradigm.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-38&engl=0}
}
@inproceedings {INPROC-2010-32,
author = {Lars Geiger and Frank D{\"u}rr and Kurt Rothermel},
title = {{Aggregation of User Contexts in Context-based Communication}},
booktitle = {Proceedings of the 6th Euro-NF Conference on Next Generation Internet (NGI 2010)},
address = {Paris},
publisher = {IEEE Xplore},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--8},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2010},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols,
C.2.4 Distributed Systems,
C.2.6 Internetworking},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-32/INPROC-2010-32.pdf,
http://dx.doi.org/10.1109/NGI.2010.5534466},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {A context-based communication system enables the indirect addressing and
routing of messages according to the users' contexts. This provides, for
example, the means to send a message to all students on campus who attend a
certain class, with information about an upcoming exam. However, for a targeted
forwarding of messages towards users, the routers need information about the
context of connected users. Global knowledge, i.e., each router knowing about
every user, is not scalable, though, because of the necessary update messages
to keep this information up-to-date.
To address this challenge, a router can aggregate similar contexts and only
provide such an aggregated view to neighboring routers. In this paper, we
present an approach to aggregate similar contexts, based on a similarity
measure for user contexts. The algorithm can be adjusted according to the
observed messages and user contexts in the system by specifying a similarity
threshold to determine when contexts are aggregated.
The aggregation of user contexts improves the scalability of our approach by
significantly reducing the load of context updates by up to 30\%, depending on
the usage of the system. This improvement comes at the cost of a negligible
increase in false positive messages due to the loss of information used for
forwarding messages.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-32&engl=0}
}
@inproceedings {INPROC-2010-31,
author = {Muhammad Adnan Tariq and Gerald Georg Koch and Boris Koldehofe and Imran Khan and Kurt Rothermel},
title = {{Dynamic publish/subscribe to meet subscriber-defined delay and bandwidth constraints}},
booktitle = {The Sixteenth International Conference on Parallel Computing (Euro-Par 2010)},
publisher = {Springer},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {458--470},
type = {Konferenz-Beitrag},
month = {August},
year = {2010},
keywords = {Content-based; P2P; Event-based; Bandwidth; End-to-end Delay; Spatial indexing; QoS},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-31/INPROC-2010-31.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Current distributed publish/subscribe systems assume that all participants have
similar QoS requirements and equally contribute to the system’s resources.
However, in many real-world applications, the message delay tolerance of
individual peers may differ widely. Disseminating messages according to
individual delay requirements not only allows for the satisfaction of
user-specific needs but also significantly improves the utilization of the
resources in a publish/subscribe system. In this paper, we propose a
peer-to-peer-based approach to satisfy the individual delay requirements of
subscribers in the presence of bandwidth constraints. Our approach allows
subscribers to dynamically adjust the granularity of their subscriptions
according to their bandwidth constraints and delay requirements. Subscribers
maintain the publish/subscribe overlay in a decentralized manner by
establishing connections to peers that provide messages meeting exactly their
subscription granularity and complying to their delay requirements. Evaluations
show that for practical workloads, the proposed system scales up to a large
number of subscribers and performs robustly in a very dynamic setting.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-31&engl=0}
}
@inproceedings {INPROC-2010-30,
author = {Andreas Grau and Klaus Herrmann and Kurt Rothermel},
title = {{NETplace: Efficient Runtime Minimization of Network Emulation Experiments}},
booktitle = {Proceeding of the International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS'10) [Best Paper Award]},
address = {Ottawa, Canada},
publisher = {IEEE Communications Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {265--272},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-30/INPROC-2010-30.pdf,
http://www.ipvs.uni-stuttgart.de/abteilungen/vs/abteilung/mitarbeiter/andreas.grau_infos/spects10bestpaper.jpg,
http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5589304},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Network emulation is an efficient method for evaluating distributed
applications and communication protocols by combining the benefits of real
world experiments and network simulation. The process of network emulation
involves execution of thousands of connected virtual nodes running the software
under test in a controlled environment. Along with the quality of the
experiment results, the runtime of network experiments strongly influences the
convenience of users and operators of emulation testbeds. The goal of this
paper is, therefore, to minimize the experiment runtime of network emulations.
In order to achieve this goal, we make the following contributions in this
paper: First, we present a highly scalable emulation architecture to
efficiently support network emulation testbeds with multicore CPUs. Second, we
propose a detailed and generic cost model for the communication costs of
emulation testbeds. Third, we present an efficient placement strategy
(NETplace) to assign virtual nodes to physical nodes of the testbed while
minimizing the runtime of network experiments. Therefore, we combine graph
partitioning and greedy approaches. Our evaluations show that our placement
strategy outperforms existing methods by reducing the experiment runtime up to
64\%.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-30&engl=0}
}
@inproceedings {INPROC-2010-24,
author = {Muhammad Adnan Tariq and Boris Koldehofe and Ala Altaweel and Kurt Rothermel},
title = {{Providing basic security mechanisms in broker-less publish/subscribe systems}},
booktitle = {Proceedings of the 4th International Conference on Distributed Event-Based Systems (DEBS'10), 2010},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {38--49},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
keywords = {Content-based; P2P; Broker-less; Security; Identity-based encryption; IBE; Attribute-based encryption; Clustering},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-24/INPROC-2010-24.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The provisioning of basic security mechanisms such as authentication and
confidentiality is highly challenging in a content-based publish/subscribe
system. Authentication of publishers and subscribers is difficult to achieve
due to the loose coupling of publishers and subscribers. Similarly,
confidentiality of events and subscriptions conflicts with contentbased
routing. In particular, content-based approaches in broker-less environments do
not address confidentiality at all. This paper presents a novel approach to
provide confidentiality and authentication in a broker-less content-based
publish-subscribe system. By adapting the pairing-based cryptography mechanisms
to the needs of publish/subscribe authentication of publisher and subscriber as
well as confidentiality of events is ensured. Furthermore, an algorithm to
cluster subscribers according to their subscriptions preserves a weak notion of
subscription confidentiality. Our approach provides fine grained key management
and the cost for encryption, decryption and routing is in the order of
subscribed attributes. Moreover, the simulation results verify that supporting
security is affordable with respect to the cost for overlay construction and
event dissemination latencies, thus preserving scalability of the system.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-24&engl=0}
}
@inproceedings {INPROC-2010-22,
author = {Bj{\"o}rn Schilling and Boris Koldehofe and Udo Pletat and Kurt Rothermel},
title = {{Distributed Heterogeneous Event Processing: Enhancing Scalability and Interoperability of CEP in an Industrial Context}},
booktitle = {Proceedings of the 4th ACM International Conference on Distributed Event-Based Systems (DEBS); Cambridge, United Kingdom, July 12-15, 2010},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {150--159},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
isbn = {1827418.1827453},
language = {Deutsch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-22/INPROC-2010-22.pdf,
http://portal.acm.org/citation.cfm?doid=1827418.1827453},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Although a significant amount of research has investigated the benefits of
distributed CEP in terms of scalability and extensibility, there is an ongoing
reluctance in deploying distributed CEP in an industrial context. In this paper
we present the DHEP system developed together with the IBM laboratory in
B{\"o}blingen. It addresses some of the key problems in increasing the acceptance
of distributed CEP, for example supporting interoperability between
heterogeneous event processing systems. We present the concepts behind the DHEP
system and show how those concepts help to achieve scalable and extensible
event processing in an industrial context. Moreover, we verify in an evaluation
study that the additional cost imposed by the DHEP system is moderate and
'affordable' for the benefits provided.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-22&engl=0}
}
@inproceedings {INPROC-2010-21,
author = {Gerald Georg Koch and Boris Koldehofe and Kurt Rothermel},
title = {{Cordies: Expressive event correlation in distributed systems}},
booktitle = {Proceedings of the 4th International Conference on Distributed Event-Based Systems (DEBS'10)},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {26--37},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2010},
isbn = {978-1-60558-927-5},
doi = {10.1145/1827418.1827424},
keywords = {Cordies; distributed complex event processing; restriction graph; correlation description},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-21/INPROC-2010-21.pdf,
http://doi.acm.org/10.1145/1827418.1827424},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Complex Event Processing (CEP) is the method of choice for the observation of
system states and situations by means of events. A number of systems have been
introduced that provide CEP in selected environments. Some are restricted to
centralised systems, or to system with synchronous communication, or to a
limited space of event relations that are defined in advance. Many modern
systems, though, are inherently distributed and asynchronous, and require a
more powerful CEP. We present Cordies, a distributed system for the detection
of correlated events that is designed for the operation in large-scale,
heterogeneous networks and adapts dynamically to changing network conditions.
With its expressive language to describe event relations, it is suitable for
environments where neither the event space nor the situations of interest are
predefined but are constantly adapted.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-21&engl=0}
}
@inproceedings {INPROC-2010-18,
author = {Andreas Benzing and Boris Koldehofe and Kurt Rothermel},
title = {{Distributed Diagnostic Simulations for the Smart Grid}},
booktitle = {Accepted Poster at the 1st International Conference on Energy-Efficient Computing and Networking: E-Energy 2010},
publisher = {Online},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--3},
type = {Konferenz-Beitrag},
month = {April},
year = {2010},
keywords = {Diagnostic Simulation; Global Sensor Grid},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-18/INPROC-2010-18.pdf},
contact = {andreas.benzing@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Energy efficiency is usually achieved by reducing the energy consumption as far
as possible. With the growing amount of renewable energy sources, energy
efficient usage also has to consider what kind of and when power is consumed.
By matching the availability of electrical power with the current demands, the
amount of unused energy and therefore overall energy production can be reduced.
The so called smart grid aims to provide this matching with a broad deployment
of smart meters to acquire the current demand. However, current approaches to
the smart grid cannot handle the huge amount of sensors and energy sources
involved in a scalable way. Most data acquisition systems focus on the lookup
and reading of single sensors and therefore do not fit the requirements of a
large scale power grid simulation. We propose a Global Sensor Grid (GSG) which
provides consumers with data preprocessed to their needs instead of delivering
raw sensor data. With this decoupling from the actual sensors, multiple
consumers can benefit from improvements in data acquisition and avoidance of
the redundant processing of data by each consumer. By integrating so-called
diagnostic simulations into the GSG, gaps in sensor coverage can be filled with
higher precision than normal interpolation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-18&engl=0}
}
@inproceedings {INPROC-2010-17,
author = {Frank D{\"u}rr and Harald Weinschrott and Kurt Rothermel},
title = {{Geocast Routing of Symbolically Addressed Messages in Wireless Mesh Networks}},
booktitle = {Proceedings of the 8th IEEE International Conference on Pervasive Computing and Communications Workshops (PerCom Workshops '10)},
address = {Mannheim, Germany},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {552--557},
type = {Workshop-Beitrag},
month = {M{\"a}rz},
year = {2010},
language = {Englisch},
cr-category = {C.2.2 Network Protocols},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-17/INPROC-2010-17.pdf,
http://dx.doi.org/10.1109/PERCOMW.2010.5470499},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Geocast protocols can be used to send messages to all receivers in a geographic
target area. In this paper we present geocast routing algorithms for Wireless
Mesh Networks that are tailored to symbolic addressing using symbolic location
names like floor or room numbers. Since in particular indoors no geometric
information is available, our algorithms use symbolic location models to derive
directional information for routing. Moreover, we show how to integrate
geometric and symbolic geographic routing algorithms into a hybrid routing
approach which is applicable to larger areas consisting of symbolically and
geometrically defined locations.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-17&engl=0}
}
@inproceedings {INPROC-2010-16,
author = {Harald Weinschrott and Frank D{\"u}rr and Kurt Rothermel},
title = {{Symbolic Routing for Location-based Services in Wireless Mesh Networks}},
booktitle = {Proceedings of the IEEE 24nd International Conference on Advanced Information Networking and Applications},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--8},
type = {Konferenz-Beitrag},
month = {April},
year = {2010},
language = {Englisch},
cr-category = {C.2.2 Network Protocols},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-16/INPROC-2010-16.pdf,
http://dx.doi.org/10.1109/AINA.2010.71},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Wireless Mesh Networks are cost-efficient medium-scale networks that have the
potential to serve as an infrastructure for advanced location-based services.
As a basis for these services we present a routing algorithm that allows to
address intuitive symbolic coordinates. This algorithm is based on a
proactively maintained geographic routing structure that mimics the structure
of a symbolic location model. Message forwarding is done greedily along short
paths defined by a symbolic location model and if this fails, through an
hierarchical overlay network built by selected mesh routers. We show how a
geocast communication mechanism that allows to send messages to all hosts
within a specific location can be implemented with this routing algorithm. In
extensive evaluations we show that a low proactive routing overhead allows to
achieve high message delivery rates even in case of mobility. Moreover, we show
that the paths achieved are only 25\% longer than the theoretic optimal paths
for a wide range of simulation settings.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-16&engl=0}
}
@inproceedings {INPROC-2010-15,
author = {Ralph Lange and Frank D{\"u}rr and Kurt Rothermel},
title = {{Efficient Tracking of Moving Objects using Generic Remote Trajectory Simplification (Demo Paper)}},
booktitle = {Proceedings of the 8th IEEE International Conference on Pervasive Computing and Communications Workshops (PerCom Workshops '10). Mannheim, Germany. March 2010},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {829--831},
type = {Workshop-Beitrag},
month = {M{\"a}rz},
year = {2010},
keywords = {Remote trajectory simplification; tracking; dead reckoning; moving objects database; MOD; line simplification},
language = {Englisch},
cr-category = {H.2.8 Database Applications},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-15/INPROC-2010-15.pdf,
http://dx.doi.org/10.1109/PERCOMW.2010.5470553},
contact = {ralph.lange@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Position information of moving objects plays a vital role in many pervasive
applications. Therefore, moving objects databases (MODs), which can manage
trajectory data of a number objects, are used in many pervasive systems. A
crucial problem with MODs is how to efficiently track a remote object's
trajectory in real-time, i.e. how to continuously report the sensed trajectory
data to the MOD with minimal effort. For this purpose, we present a
prototypical implementation of the Generic Remote Trajectory Simplification
(GRTS) protocol, which optimizes storage consumption, processing, and
communication costs. Our prototypical system includes a fully functional MOD as
well as map-based mobile applications for subnotebooks and smartphones to
illustrate the functioning of GRTS.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-15&engl=0}
}
@inproceedings {INPROC-2010-118,
author = {Frank D{\"u}rr and Marius Wernke and Pavel Skvortsov and Kurt Rothermel},
title = {{Towards a Position Sharing Approach for Location-based Services}},
booktitle = {Proceedings of the W3C Workshop on Privacy for Advanced Web APIs},
publisher = {Online},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--3},
type = {Workshop-Beitrag},
month = {Juli},
year = {2010},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
H.3.5 Online Information Services},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-118/INPROC-2010-118.pdf,
http://www.w3.org/2010/api-privacy-ws/papers/privacy-ws-16.pdf,
http://www.priloc.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In partially-trusted system environments like the WWW, the management of
private user positions is a great challenge. On the one hand, location-based
services of different partially-trusted providers have to be provided with
position information. On the other hand, location servers, which are
responsible for the management of user positions, might as well be operated by
only partially-trusted providers. Therefore, in order to protect his privacy, a
user might only want to store position information of limited precision on
location servers, and also provide location-based services with position
information of limited precision.
In this position paper, we sketch a novel position sharing approach that
enables the user to tightly control the precision of position information
stored on servers and provided to location-based services. This approach is
based on the idea of distributing position information among a set of servers
of different providers such that a compromised server only reveals information
of strictly limited precision.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-118&engl=0}
}
@inproceedings {INPROC-2010-116,
author = {Faraz Memon and Daniel Tiebler and Frank D{\"u}rr and Kurt Rothermel},
title = {{Optimized Information Discovery using Self-adapting Indices over Distributed Hash Tables}},
booktitle = {Proceedings of 29th International Performance Computing and Communications Conference (IPCCC'10)},
address = {Albuquerque, New Mexico, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--9},
type = {Konferenz-Beitrag},
month = {Dezember},
year = {2010},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
E.1 Data Structures,
E.2 Data Storage Representations,
H.3.1 Content Analysis and Indexing},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-116/INPROC-2010-116.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Distributed Hash Table (DHT)-based peer-to-peer information discovery systems
have emerged as highly scalable systems for information storage and discovery
in massively distributed networks. Originally DHTs supported only point
queries. However, recently they have been extended to support more complex
queries, such as multi-attribute range (MAR) queries. Generally, the support
for MAR queries over DHTs has been provided either by creating an individual
index for each data attribute or by creating a single index using the
combination of all data attributes. In contrast to these approaches, we propose
to create and modify indices using the attribute combinations that dynamically
appear in MAR queries in the system.
In this paper, we present an adaptive information discovery system that adapts
the set of indices according to the dynamic set of MAR queries in the system.
The main contribution of this paper is a four-phase scalable index adaptation
process. Our evaluations show that the adaptive information discovery system
continuously optimizes the overall system performance for MAR queries.
Moreover, compared to a non-adaptive system, the adaptive information discovery
system shows several orders of magnitude improved performance.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-116&engl=0}
}
@inproceedings {INPROC-2010-06,
author = {Stephan Schuhmann and Klaus Herrmann and Kurt Rothermel},
title = {{Efficient Resource-Aware Hybrid Configuration of Distributed Pervasive Applications}},
booktitle = {Proceedings of the 8th International Conference on Pervasive Computing (Pervasive 2010); Helsinki, Finland, May 17-20, 2010},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Lecture Notes in Computer Science},
volume = {6030},
pages = {373--390},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2010},
keywords = {Adaptivity; Components; Distributed Application Configuration; Heterogeneous Environments; Middleware; Pervasive Applications},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2010-06/INPROC-2010-06.pdf,
http://www.springerlink.com/content/x6607vl0w9753683/},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {As the size and complexity of Pervasive Computing environments increases,
configuration and adaptation of distributed applications gains importance.
These tasks require automated system support, since users must not be
distracted by the (re-)composition of applications. In homogeneous ad hoc
scenarios, relying on decentralized configuration schemes is obviously
mandatory, while centralized approaches may help to reduce latencies in weakly
heterogeneous infrastructure-based environments. However, in case of strongly
heterogeneous pervasive environments including several resource-rich and
resource-weak devices, both approaches may lead to suboptimal results
concerning configuration latencies: While the resource-weak devices represent
bottlenecks for decentralized configuration, the centralized approach faces the
problem of not utilizing parallelism. Instead, a hybrid approach that involves
only the subset of resource-rich devices is capable of rendering configuration
and adaptation processes more efficiently. In this paper, we present such a
resource-aware hybrid scheme that effectively reduces the time required for
configuration processes. This is accomplished by a balanced-load clustering
scheme that exploits the computational power of resource-rich devices, while
avoiding bottlenecks in (re-)configurations. We present real-world evaluations
which confirm that our approach reduces configuration latencies in
heterogeneous environments by more than 30 \% compared to totally centralized
and totally decentralized approaches. This is an important step towards
seamless application configuration.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-06&engl=0}
}
@article {ART-2010-03,
author = {Sven Schulz and Wolfgang Blochinger and Mathias Poths},
title = {{Orbweb - A Network Substrate for Peer-to-Peer Grid Computing Platforms based on Open Standards}},
journal = {Journal of Grid Computing},
address = {Heidelberg},
publisher = {Springer-Verlag},
volume = {8},
number = {1},
pages = {77--107},
type = {Artikel in Zeitschrift},
month = {Juni},
year = {2010},
doi = {10.1007/s10723-009-9121-8},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols,
C.2.4 Distributed Systems,
C.2.6 Internetworking},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In this paper, we propose to use the open industrial-strength eXtensible
Messaging and Presence Protocol (XMPP) to build a network substrate for
Peer-to-Peer Grid computing called Orbweb. We describe how to employ XMPP to
tackle domain-specific challenges, including high scalability, support for
volatility, NAT/Firewall traversal, and protocol efficiency. Where XMPP fails
to meet these requirements, we contribute pertinent extensions. In particular,
we boost the scalability of XMPP by taking load of the XMPP servers through
dynamically negotiated direct Peer-to-Peer communication channels between XMPP
peers. We pave the way for scalable group membership management by substituting
the existing XMPP Multi-User Chat protocol for one that does not suffer from
limitations imposed by a everyone knows everyone visibility model and allows
for selecting a membership model that matches the requirements of a given
application. As efficient multicasting is an essential prerequisite for many
distributed algorithms and the centralized XMPP multicast is of limited
scalability, we adapt the well-known Bimodal Multicast protocol to work in a
highly volatile Peer-to-Peer Grid computing environment. Finally, we show how
to improve the protocol efficiency of XMPP by leveraging a standardized binary
encoding of the XML Information Set for XMPP packet transmission. To
substantiate the applicability of our approach and the effectiveness of our
extensions, we describe how some important higher-level services used in
Peer-to-Peer Grid Computing can be implemented on top of Orbweb and provide a
detailed experimental analysis.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2010-03&engl=0}
}
