Publikationen VS: Bibliographie 2007 BibTeX
@inproceedings {INPROC-2007-84,
author = {Dominique Dudkowski and Pedro Jos{\'e} Marr{\'o}n and Kurt Rothermel},
title = {{Migration Policies for Location-Centric Data Storage in Mobile Ad-Hoc Networks}},
booktitle = {Proceedings of the 3rd International Conference on Mobile Ad-hoc and Sensor Networks (MSN'07); Beijing, China, December, 2007},
publisher = {Springer},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {197--208},
type = {Konferenz-Beitrag},
month = {Dezember},
year = {2007},
keywords = {location-centric; MANET; migration},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Location-centric data storage is a fundamental paradigm for data management in
wireless ad-hoc networks. It guarantees that data is stored at network nodes
near specific geometric reference locations in the region where the network is
deployed. In mobile ad-hoc networks, maintaining spatial proximity between data
and its associated location requires explicit migration mechanisms in order to
``keep the data in place''. In this paper we propose comprehensive policies for
data migration that effectively maintain the spatial coherence of data given
the particular characteristics of mobile ad-hoc networks. Using extensive
simulations we show how the proposed policies outperform related migration
approaches over a wide range of system parameter settings, in particular, node
density, network dynamics, and migratable data size.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-84&engl=0}
}
@inproceedings {INPROC-2007-83,
author = {J{\"o}rg H{\"a}hner and Dominique Dudkowski and Pedro Jos{\'e} Marr{\'o}n and Kurt Rothermel},
title = {{Quantifying Network Partitioning in Mobile Ad Hoc Networks.}},
booktitle = {Proceedings of the 8th International Conference on Mobile Data Management (MDM 2007), Mannheim, Germany, May 2007},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {174--181},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2007},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The performance of distributed algorithms in mobile ad hoc networks is strongly
influenced by the connectivity of the network. In cases where the connectivity
is low, network partitioning occurs. The mobility and the density of network
nodes as well as the communication technology are fundamental properties that
have a large impact on partitioning. A detailed characterization of this
behavior helps to improve the performance of distributed algorithms.
In this paper we introduce a set of metrics that characterize partitioning in
mobile ad hoc networks. Based on an extensive simulation study we show the
impact of node mobility, density and transmission range on the proposed metrics
for a wide range of network scenarios.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-83&engl=0}
}
@inproceedings {INPROC-2007-73,
author = {Sebastien Baehni and Rachid Guerraoui and Boris Koldehofe and Maxime Monod},
title = {{Towards Fair Event Dissemination}},
booktitle = {Proceedings of the 27th IEEE International Conference on Distributed Computing Systems Workshops (ICDCSW'07)},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2007},
doi = {10.1109/ICDCSW.2007.83},
language = {Englisch},
cr-category = {C.2.2 Network Protocols,
C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-73/INPROC-2007-73.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Event dissemination in large scale dynamic systems is typically claimed to be
best achieved using decentralized peer-to-peer architectures. The rationale is
to have every participant in the system act both as a client (information
consumer) and as a server (information dissemination enabler), thus, precluding
specific brokers which would prevent scalability and fault-tolerance. We argue
that, for such decentralized architectures to be really meaningful,
participants should serve the system as much as they benefit from it. That is,
the system should be fair in the sense that the extend to which a participant
acts as a server should depend on the extend to which it has the opportunity to
act as a client. This is particularly crucial in selective information
dissemination schemes where clients are not all interested in the same
information. In this position paper, we discuss what a notion of fairness could
look like, explain why current architectures are not fair, and raise several
challenges towards achieving fairness.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-73&engl=0}
}
@inproceedings {INPROC-2007-57,
author = {The SpoVNet Consortium and Boris Koldehofe and Gerald Georg Koch},
title = {{SpoVNet: An Architecture for Supporting Future Internet Applications}},
booktitle = {Proc. 7th W{\"u}rzburg Workshop on IP: Joint EuroFGI and ITG Workshop on ``Visions of Future Generation Networks''},
address = {W{\"u}rzburg, Germany},
publisher = {-},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
type = {Workshop-Beitrag},
month = {Juli},
year = {2007},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-57/INPROC-2007-57.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {This talk presents an approach for providing Spontaneous Virtual Networks
(SpoVNets) that enable flexible, adaptive, and spontaneous provisioning of
application-oriented and network-oriented services on top of heterogeneous
networks. SpoVNets supply new and uniform communication abstractions for future
Internet applications so applications can make use of advanced services not
supported by today's Internet. We expect that many functions, which are
currently provided by SpoVNet on the application layer will become an integral
part of future networks. Thus, SpoVNet will transparently use advanced services
from the underlying network infrastructure as they become available (e.g.,
QoS-support in access networks or multicast in certain ISPs), enabling a
seamless transition from current to future genera-tion networks without
modifying the applications.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-57&engl=0}
}
@inproceedings {INPROC-2007-55,
author = {Klaus Herrmann},
title = {{Group Anti-Entropy - Achieving Eventual Consistency in Mobile Service Environments}},
booktitle = {Proceedings of the 8th IEEE International Conference on Mobile Data Management (MDM'07)},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
type = {Konferenz-Beitrag},
month = {Januar},
year = {2007},
keywords = {mobility, ambient services, data consistency, optimistic replication},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
H.2 Database Management},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-55/INPROC-2007-55.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Data consistency protocols are vital ingredients of mobile data management
systems. Notable research efforts have been spent to find adequate consistency
models for allowing mobile and nomadic users to share mutable data. Recently,
mobile Ambient Service infrastructures that pose somewhat different
requirements have entered the focus of attention. Such services are not as
loosely coupled as the afore-mentioned systems, but they still need flexible
consistency protocols that may adapt to the current dynamics in the system. We
propose an extension to the well-known anti-entropy protocol that makes use of
the nature of Ambient Service environments to allow for a flexible consistency
management among arbitrary groups of mobile service replicas. We will show that
our protocol can exploit the concept of group updates to increase its
efficiency in terms of bandwidth usage. Furthermore, we prove that it avoids
costly state transfers by means of a simple rule that limits the divergence
within the overall set of replicas. Finally, we introduce two simple tunable
parameters, and we present experimental results that show how they may be used
to shape the characteristics of the protocol.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-55&engl=0}
}
@inproceedings {INPROC-2007-54,
author = {Gero M{\"u}hl and Matthias Werner and Michael A. Jaeger and Klaus Herrmann and Helge Parzyjegla},
title = {{On the Definitions of Self-Managing and Self-Organizing Systems}},
booktitle = {KiVS 2007 Workshop: Selbstorganisierende, Adaptive, Kontextsensitive verteilte Systeme (SAKS 2007)},
address = {Bern, Switzerland},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Informatik aktuell},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
keywords = {self-organization, self-management, adaptivity, classification, formal model},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
F.1.1 Models of Computation},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-54/INPROC-2007-54.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The management costs of software systems are becoming the dominating cost
factor in running IT infrastructures. The main driving force behind this
development is the ever-increasing system complexity which is becoming the
limiting factor for further development. The fact that human administrators get
more and more overstrained by management tasks has led to the idea of systems
that manage themselves, i.e., self-managing systems. Another concept that is
closely related to selfmanagement is self-organization. Self-organizing
software systems often build on bio- and nature-inspired approaches. However,
most publications on self-managing or self-organizing systems miss a clear
definition of these terms. Even worse, although self-management and
self-organization aim at similar goals, their relation still has not been
defined properly. In this paper, we approach these problems by introducing a
classification of systems that models self-organizing systems as a subclass of
selfmanaging systems. The classification builds upon a definition of adaptive
systems and introduces self-manageable, self-managing, and selforganizing
systems. Our proposal serves as a starting point for further discussions,
eventually leading to a better understanding of the terms self-organization and
self-management and their interrelationship.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-54&engl=0}
}
@inproceedings {INPROC-2007-53,
author = {Michael A. Jaeger and Helge Parzyjegla and Gero M{\"u}hl and Klaus Herrmann},
title = {{Self-Organizing Broker Topologies for Publish/Subscribe Systems}},
booktitle = {The 22nd Annual ACM Symposium on Applied Computing},
address = {Seoul, Korea},
publisher = {ACM Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {543--550},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
keywords = {publish/subscribe, adaptable middleware, self-organization, overlay networks},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-53/INPROC-2007-53.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Distributed publish/subscribe systems are usually deployed on top of an overlay
network that enables complex routing strategies implemented in the application
layer. Up to now, only little effort has been spent on the design of the broker
overlay network assuming that it is either static or manually administered. As
publish/subscribe systems are increasingly targeted at dynamic environments
where client behavior and network characteristics vary over time, static
overlay networks lead to suboptimal performance. In this paper, we present a
self-organizing broker overlay infrastructure that adapts dynamically to
achieve a better efficiency on both, the application and the network layer.
This is obtained by taking network metrics as well as notification traffic into
account.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-53&engl=0}
}
@inproceedings {INPROC-2007-51,
author = {Klaus Herrmann},
title = {{Self-Organizing Replica Placement - A Case Study on Emergence}},
booktitle = {Proceedings of the first IEEE International Conference on Self-Adaptive and Self-Organizing Systems},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {13--22},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2007},
keywords = {self-organization, emergence, replica placement, case study},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
H Information Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-51/INPROC-2007-51.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The concept of self-organization is rapidly gaining importance in the area of
distributed computing systems. However, we still lack the necessary means for
engineering such system in a standardized way since their common properties are
rather abstract, and the mechanisms from which self-organization emerges are
too diverse. Therefore, it has become common practice to engineer computing
systems by taking inspirations from well-known case studies of biological
systems. However, the concepts found in such systems are in many cases only
partially transferable to the domain of distributed computing systems since
biological systems are subject to vastly different constraints compared to
those in a computing system. Our contributions in this paper are the following:
(i) We present a case study of a self-organizing software system that
originates from the domain of distributed computing systems. Therefore, its
concepts can be exploited in other distributed computing systems much more
directly. (ii) We give a detailed analysis of the emergent properties of the
system and the mechanisms by which they arise. (iii) We generalize the
mechanisms by which self-organization emerges in this system and present a
catalog of design questions that may help engineers in creating arbitrary
self-organizing systems.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-51&engl=0}
}
@inproceedings {INPROC-2007-50,
author = {Klaus Herrmann},
title = {{Self-Organizing Infrastructures for Ambient Services}},
booktitle = {Kommunikation in Verteilten Systemen (KiVS), 15. ITG/GI Fachtagung Kommunikation in Verteilten Systemen (KiVS 2007)},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Informatik aktuell},
pages = {299--306},
type = {Konferenz-Beitrag},
month = {Januar},
year = {2007},
isbn = {3-540-69961-9},
keywords = {self-organization, middleware, data consistency, lookup service, mobile ad hoc networks, replica placement, wireless mesh networks},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-50/INPROC-2007-50.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The vision of Ambient Intelligence (AmI) as a new paradigm for supporting the
mobile user in his daily activities is currently entering the focus of European
research efforts. A high degree of autonomy on the part of the supporting
software system is inherent to this vision of omnipresent and continuously
running services. However, adequate concepts for creating respective
infrastructures that may operate autonomously and in a self-organized fashion
are still largely unexplored. We propose the Ad hoc Service Grid (ASG) as a
dedicated AmI infrastructure that may be deployed in an ad hoc fashion at
arbitrary medium-sized locations (shopping malls, construction sites, trade
fairs, etc.). In this paper, we give an overview over our results thus far. We
focus on the problems of service placement, discovery and lookup, and data
consistency within an ASG environment and show how we have solved these
problems with new self-organizing and adaptive algorithms. These vital
functions are the basis for the realization of ASG systems and represent an
essential contribution to AmI research in general.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-50&engl=0}
}
@inproceedings {INPROC-2007-48,
author = {Marcus Handte and Klaus Herrmann and Gregor Schiele and Christian Becker and Kurt Rothermel},
title = {{Automatic Reactive Adaptation of Pervasive Applications}},
booktitle = {Proceedings of ICPS'07: IEEE International Conference on Pervasive Services},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {214--222},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2007},
keywords = {adaptivity, components, mobility, optimization},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-48/INPROC-2007-48.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive Computing envisions seamless and distraction-free support for
everyday tasks through distributedapplications that leverage the resources of
the users' environment. Due to the mobility of users and devices, applications
need to adapt continuously to their changing execution environment. Therefore,
developers need a suitable framework in order to efficiently create adaptive
applications. In this paper, we present and evaluate our approach to adapting a
pervasive computing application to changes during its execution. This work is
based on the minimal component system PCOM and on an algorithm to fully
automate the initial configuration of a componentbased application which we
have presented in earlier work. The contribution of this paper is threefold.
First, we describe a number of modifications to the component model that are
required to enable fully automatic adaptation. Secondly, we propose a simple
yet powerful cost model to capture the complexity of specific adaptations.
Thirdly, we describe an online optimization heuristic that extends our
distributed configuration algorithm in order to choose to a low-cost
configuration whenever the current configuration of a pervasive application
requires adaptation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-48&engl=0}
}
@inproceedings {INPROC-2007-46,
author = {Matthias Gauger and Pedro Jos{\'e} Marr{\'o}n and Daniel Kauker and Kurt Rothermel},
title = {{Low Overhead Assignment of Symbolic Coordinates in Sensor Networks}},
booktitle = {Proceedings of the IFIP First International Conference on Wireless Sensor and Actor Networks, WSAN'07},
editor = {Luis Orozco-Barbosa and Teresa Olivares and Rafael Casado and Aurelio Berm{\'u}dez},
publisher = {Springer},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {181--192},
type = {Konferenz-Beitrag},
month = {September},
year = {2007},
isbn = {978-0-387-74898-6},
language = {Englisch},
cr-category = {C.3 Special-Purpose and Application-Based Systems},
contact = {gauger@cs.uni-bonn.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Approximate information on the location of nodes in a sensor network is
essential to many types of sensor network applications and algorithms. In many
cases, using symbolic coordinates is an attractive alternative to the use of
geographic coordinates due to lower costs and lower requirements on the
available location information during coordinate assignment. In this paper, we
investigate different possible methods of assigning symbolic coordinates to
sensor nodes. We present a method based on broadcasting coordinate messaging
and filtering using sensor events. We show in the evaluation that this method
allows a reliable assignment of symbolic coordinates while only generating a
low overhead.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-46&engl=0}
}
@inproceedings {INPROC-2007-45,
author = {Daniel Minder and Pedro Jos{\'e} Marr{\'o}n and Andreas Lachenmann and Kurt Rothermel},
title = {{Coordinated group adaptation in sensor networks}},
booktitle = {6. Fachgespr{\"a}ch Sensornetzwerke},
publisher = {RWTH Aachen},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Technischer Bericht},
volume = {AIB 2007-11},
pages = {43--46},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2007},
issn = {0935-3232},
keywords = {wireless sensor network; group adaptation; coordination},
language = {Englisch},
cr-category = {D.4.7 Operating Systems Organization and Design,
C.2.1 Network Architecture and Design,
C.2.3 Network Operations},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-45/INPROC-2007-45.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In Wireless Sensor Networks, several algorithms are used to perform different
functionality, e.g. routing or clock synchronization. Each algorithm is
intended for specific network characteristics and user requirements. But the
acutal characteristics and requirements may change during system runtime.
TinyCubus and particularly its Tiny Data Managment Framework use adaptation to
solve this problem.
In this paper, we first explain the centralized adaptation process. Then, we
examine how this can be done localized in the network. Since coordination
between local adaptation decisions is found to be necessary, metrics for this
coordination and their dependencies are shown.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-45&engl=0}
}
@inproceedings {INPROC-2007-38,
author = {Lars Geiger and Frank D{\"u}rr},
title = {{Kontextbezogene Kommunikation}},
booktitle = {4. GI/ITG KuVS Fachgespr{\"a}ch Ortsbezogene Anwendungen und Dienste},
editor = {J{\"o}rg Roth and Axel K{\"u}pper and Claudia Linnhoff-Popien},
address = {M{\"u}nchen},
publisher = {Verlag Dr. Hut},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {22--26},
type = {Konferenz-Beitrag},
month = {September},
year = {2007},
isbn = {978-3-89963-591-1},
keywords = {Kontext; Kommunikation; Multicast; Nexus},
language = {Deutsch},
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-2007-38/INPROC-2007-38.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Verbindet man die Position eines Benutzers mit weiteren Attributen wie
beispielsweise Typ, Alter oder Status zu seinem Kontext, so ergeben sich daraus
interessante neue Anwendungsm{\"o}glichkeiten. In diesem Artikel soll ein Verfahren
vorgestellt werden, wie ein solcher Kontext benutzt werden kann, um Nachrichten
an bestimmte Gruppen von Benutzern --- bestimmt durch ihren Kontext --- zu
versenden. Ein solcher Kommunikationsmechanismus k{\"o}nnte beispielsweise
eingesetzt werden, um Verkehrsnachrichten gezielt an alle Fahrzeuge innerhalb
eines bestimmten Gebietes und mit einer bestimmten Fahrtrichtung zu
{\"u}bermitteln.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-38&engl=0}
}
@inproceedings {INPROC-2007-35,
author = {Tobias Farrell and Reynold Cheng and Kurt Rothermel},
title = {{Energy-Efficient Monitoring of Mobile Objects with Uncertainty-Aware Tolerances}},
booktitle = {Proceedings of the 11th International Database Engineering and Applications Symposium (IDEAS 2007); Banff, Canada, September 6-8, 2007},
editor = {Bipin C. Desai and Ken Barker},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {129--140},
type = {Konferenz-Beitrag},
month = {September},
year = {2007},
isbn = {0-7695-2947-X},
doi = {10.1109/IDEAS.2007.4318097},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
ee = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?isnumber=4318075&arnumber=4318097},
contact = {Tobias.Farrell@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In location-based services, continuous queries are often employed to monitor
the locations of mobile ob-jects that are determined by sensing devices like
GPS receivers. Due to limited battery resources, it is impor-tant for these
objects to acquire and report location data only if necessary. We study how
these energy-consuming operations can be reduced with a con-trolled impact on
query accuracy of continuous range queries (CRQs). Specifically, we develop
uncertainty-aware tolerances, which are user-defined error bounds that provide
correctness guarantees, with considera-tion of different sources of data
uncertainty: sensing uncertainty, sampling uncertainty, and communication
delay. Novel algorithms are developed to control carefully when an object
should acquire and update a location, while satisfying these tolerances.
Extensive simulations validate the effectiveness of our methods.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-35&engl=0}
}
@inproceedings {INPROC-2007-34,
author = {Tobias Farrell and Ralph Lange and Kurt Rothermel},
title = {{Energy-efficient Tracking of Mobile Objects with Early Distance-based Reporting}},
booktitle = {Proceedings of the Fourth Annual International Conference on Mobile and Ubiquitous Systems: Networking and Services (MobiQuitous 2007); Philadelphia, PA, USA, August 6-10, 2007},
publisher = {IEEE Press},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {August},
year = {2007},
isbn = {1-4244-1025-8},
doi = {10.1109/MOBIQ.2007.4450984},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-34/INPROC-2007-34.pdf,
http://www.ieeexplore.ieee.org/xpls/abs_all.jsp?isnumber=4450969&arnumber=4450984},
contact = {Tobias.Farrell@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Many location-based systems rely on fine-grained tracking of mobile objects
that determine their own locations with sensing devices like GPS receivers. For
these objects, energy is a very valuable and limited resource. A distance-based
reporting protocol can be employed to reduce the energy they consume by sending
position updates. However, the energy required for position sensing has not
been considered in the past. In this paper, we study how the resulting energy
consumption from both sensing and update operations can be reduced for
distance-based reporting. We show that significant savings are achieved by
sending position updates earlier than actually required. For uniform movement,
we derive the minimal power consumption analytically. Subsequently, two novel
online heuristics are proposed that control the sending of position updates at
runtime. Their effectiveness is validated by extensive simulations.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-34&engl=0}
}
@inproceedings {INPROC-2007-15,
author = {Martin Saternus and Mirko Knoll and Frank D{\"u}rr and Torben Weis},
title = {{Symstry: Ein P2P-System f{\"u}r Ortsbezogene Anwendungen}},
booktitle = {Proceedings of 15. ITG/GI - Fachtagung (KiVS 2007)},
publisher = {VDE-Verlag},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {99--104},
type = {Konferenz-Beitrag},
month = {Februar},
year = {2007},
isbn = {ISBN 978-3-8007-2980-7},
keywords = {peer-to-peer; context-aware system},
language = {Deutsch},
cr-category = {H.3.3 Information Search and Retrieval},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-15&engl=0}
}
@inproceedings {INPROC-2007-14,
author = {Martin Saternus and Torben Weis and Mirko Knoll and Frank D{\"u}rr},
title = {{A Middleware for Context-Aware Applications and Services Based on Messenger Protocols}},
booktitle = {Proceedings of the Fifth Annual IEEE International Conference on Pervasive Computing and Communications Workshops (PerComW'07)},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {467--471},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
keywords = {context-aware application; middleware; user interface; messenger},
language = {Englisch},
cr-category = {D.2.6 Software Engineering Programming Environments,
H.5.0 Information Interfaces and Presentation General},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Nowadays most context-aware applications are independent proprietary pieces of
software. A general framework or middleware deployed in the field does not
exist; therefore the implementation of context-aware applications and services
assumes the development of the whole application stack for each application.
Along these development issues, deployment and privacy problems are to be
solved.
This imposes the following challenges concerning a middleware for context-aware
applications: (1) We need an architecture that allows to implement and deploy
services easily on the network. (2) We need a user interface that is
widespread, well known to users and allows to mange one’s privacy settings for
every single service transparently.
In this paper we describe our middleware’s architecture for context-aware
applications, based on messenger protocols.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-14&engl=0}
}
@inproceedings {INPROC-2007-133,
author = {Andreas Lachenmann and Pedro Jos{\'e} Marr{\'o}n and Daniel Minder and Kurt Rothermel},
title = {{Meeting Lifetime Goals with Energy Levels}},
booktitle = {Proceedings of the 5th ACM Conference on Embedded Networked Sensor Systems (SenSys 2007)},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {131--144},
type = {Konferenz-Beitrag},
month = {November},
year = {2007},
doi = {10.1145/1322263.1322277},
keywords = {wireless sensor network; energy; lifetime goal; programming abstraction},
language = {Englisch},
cr-category = {D.3.3 Programming Language Constructs and Features,
D.4.8 Operating Systems Performance},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-133/INPROC-2007-133.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In this paper we present Levels, a programming abstraction for energy-aware
sensor network applications. Unlike most previous work it does not try to
maximize network lifetime but rather helps to meet user-defined lifetime goals
while maximizing application quality. Levels is targeted to applications where
there is no redundancy and no node should fail early.
With our programming abstraction the application developer defines so-called
energy levels. These energy levels form a stack and can be deactivated from top
to bottom if the lifetime goal cannot be met otherwise. Each code block within
an energy level contains information about its energy consumption, which can be
obtained from simulation tools without much effort. The runtime system then
uses the data about the energy consumption of the different levels to compute
an optimal level assignment for the time remaining. As we show in the
evaluation, applications using Levels can accurately meet given lifetime goals
and offer good application quality. In addition, the runtime overhead of our
system is almost negligible.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-133&engl=0}
}
@inproceedings {INPROC-2007-132,
author = {Daniel Minder and Andreas Grau and Pedro Jos{\'e} Marr{\'o}n},
title = {{On Group Formation for Self-Adaptation in Pervasive Systems}},
booktitle = {Proceedings of the First International Conference on Autonomic Computing and Communication Systems},
publisher = {ACM},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--10},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2007},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-132/INPROC-2007-132.pdf,
http://portal.acm.org/citation.cfm?doid=1365562.1365584},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Adaptation in Pervasive Computing normally focuses on services or on
application behaviour, but the consideration of lower level algorithms in this
process can lead to significant performance increase. To perform adaptation of
algorithms the concept of context normally used in Pervasive Computing has to
be extended. Based on the same context, group formation models are established
to group devices with similar relevant context to optimise the adaptation
process. In this paper, such group formation models are developed and
evaluated. We also draw general conclusions for adaptation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-132&engl=0}
}
@inproceedings {INPROC-2007-13,
author = {Marcus Handte and Klaus Herrmann and Gregor Schiele and Christian Becker},
title = {{Supporting Pluggable Configuration Algorithms in PCOM}},
booktitle = {Perware Workshop at 5th IEEE International Conference on Pervasive Computing and Communications (PerCom)},
address = {New York, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {472--476},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
language = {Englisch},
cr-category = {D.2.11 Software Engineering Software Architectures,
D.1.2 Automatic Programming},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-13/INPROC-2007-13.pdf,
http://dx.doi.org/10.1109/PERCOMW.2007.111},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive Computing envisions distributed applications that optimally leverage
the resources present in their ever-changing execution environment. To ease the
development of pervasive applications, we have created a pervasive component
system (PCOM). PCOM automates the configuration and runtime adaptation of a
component-based application using a builtin distributed configuration
algorithm. In this paper, we present an architectural extension that allows
switching between different algorithms. This enables PCOM to dynamically select
an algorithm that suits the computational resources present in an environment.
To validate the extended architecture, we compare the overheads of a
distributed and a centralized configuration algorithm in two different
environments.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-13&engl=0}
}
@inproceedings {INPROC-2007-12,
author = {Gregor Schiele and Marcus Handte and Christian Becker},
title = {{Good Manners for Pervasive Computing - An Approach Based on the Ambient Calculus}},
booktitle = {WIP Track at 5th IEEE International Conference on Pervasive Computing and Communications (PerCom)},
address = {New York, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {589--593},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
language = {Englisch},
cr-category = {D.2.7 Software Engineering Distribution, Maintenance, and Enhancement},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {When people interact, they follow distinct rules that coordinate the order of
speech, who opens doors, whom and how to greet, and many things more. Such a
social codex depends on the milieu -- or ambience -- people are acting in.
People breaking the codex are either considered badly educated or foreigners to
the ambience -- sometimes even both. In Pervasive Computing a multitude of
applications is expected to populate our environment and to follow objects and
users throughout their daily journey. Consequently, we will need a new codex --
or manners -- for Pervasive Computing applications that controls the
interaction between applications. Such a codex will have to incorporate our
existing codices as well as technical aspects. In this work in progress paper
we present an approach to extend our prior work on Pervasive Computing system
support by specifying interdependencies of applications based on the ambient
calculus. This allows specifying and technically enforcing ``manners'' for
Pervasive Computing applications.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-12&engl=0}
}
@inproceedings {INPROC-2007-05,
author = {Steffen Maier and Andreas Grau and Harald Weinschrott and Kurt Rothermel},
title = {{Scalable Network Emulation: A Comparison of Virtual Routing and Virtual Machines}},
booktitle = {Proceedings of the IEEE Symposium on Computers and Communications (ISCC'07), Aveiro, Portugal, July 1-4},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {395--402},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2007},
keywords = {network emulation; performance measurement; virtual machine; virtual routing},
language = {Englisch},
cr-category = {C.4 Performance of Systems,
D.4.4 Operating Systems Communications Management,
D.4.8 Operating Systems Performance,
I.6.3 Simulation and Modeling Applications},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-05/INPROC-2007-05.pdf,
http://dx.doi.org/10.1109/ISCC.2007.4381529},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Performance analysis is a necessary step during the development of distributed
applications and communication protocols. Network emulation testbeds provide
synthetic, configurable environments for comparative performance measurements
of real implementations. However, realistic scenarios require more
communicating nodes than usual testbeds are able to provide. In order to enable
scalable network emulation, various concepts for the virtualization of nodes
have been proposed. The overhead of virtualization strongly impacts the total
size of a scenario, that can be emulated on a given testbed. However, the
overhead of different virtualization approaches in the context of network
emulation has not been compared directly so far. In this paper, we present a
comparison of different virtual machine implementations (Xen, User Mode Linux)
and our own virtual routing approach (NET). We discuss qualitative evaluation
criteria and present a quantitative evaluation showing the efficiency of each
approach in a traditional wired infrastructure-based and in a wireless ad hoc
network emulation scenario. Our results give insights on which virtualization
approach is best suited for which kind of network emulation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-05&engl=0}
}
@inproceedings {INPROC-2007-02,
author = {Andreas Lachenmann and Pedro Jos{\'e} Marr{\'o}n and Matthias Gauger and Daniel Minder and Olga Saukh and Kurt Rothermel},
title = {{Removing the Memory Limitations of Sensor Networks with Flash-Based Virtual Memory}},
booktitle = {Proceedings of the European Conference on Computer Systems (EuroSys 2007)},
publisher = {EuroSys},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Also published in ACM SIGOPS Operating Systems Review, vol. 41(3), 2007},
pages = {131--144},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
language = {Englisch},
cr-category = {D.4.2 Storage Management,
D.3.4 Programming Languages Processors},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-02/INPROC-2007-02.pdf,
http://www.ipvs.uni-stuttgart.de/abteilungen/vs/forschung/projekte/tinycubus/start},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Virtual memory has been successfully used in different domains to extend the
amount of memory available to applications. We have adapted this mechanism to
sensor networks, where, traditionally, RAM is a severely constrained resource.
In this paper we show that the overhead of virtual memory can be significantly
reduced with compile-time optimizations to make it usable in practice, even
with the resource limitations present in sensor networks.
Our approach, ViMem, creates an efficient memory layout based on variable
access traces obtained from simulation tools. This layout is optimized to the
memory access patterns of the application and to the specific properties of the
sensor network hardware.
Our implementation is based on TinyOS. It includes a pre-compiler for nesC code
that translates virtual memory accesses into calls of ViMem’s runtime
component. ViMem uses flash memory as secondary storage. In order to evaluate
our system we have modified nontrivial existing applications to make use of
virtual memory. We show that its runtime overhead is small even for large data
sizes.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-02&engl=0}
}
@inproceedings {INPROC-2007-01,
author = {Andreas Lachenmann and Pedro Jos{\'e} Marr{\'o}n and Daniel Minder and Olga Saukh and Matthias Gauger and Kurt Rothermel},
title = {{Versatile Support for Efficient Neighborhood Data Sharing}},
booktitle = {Proceedings of the 4th European Conference on Wireless Sensor Networks (EWSN 2007)},
editor = {Koen Langendoen and Thiemo Voigt},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
series = {Lecture Notes in Computer Science},
volume = {4373},
pages = {1--16},
type = {Konferenz-Beitrag},
month = {Januar},
year = {2007},
keywords = {wireless sensor networks; neighborhood data sharing; polite gossiping},
language = {Englisch},
cr-category = {C.2.2 Network Protocols,
C.3 Special-Purpose and Application-Based Systems,
D.3.3 Programming Language Constructs and Features},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-01/INPROC-2007-01.pdf,
http://www.ipvs.uni-stuttgart.de/abteilungen/vs/forschung/projekte/tinycubus/start,
http://dx.doi.org/10.1007/978-3-540-69830-2_1},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Many applications in wireless sensor networks rely on data from neighboring
nodes. However, the effort for developing efficient solutions for sharing data
in the neighborhood is often substantial. Therefore, we present a
general-purpose algorithm for this task that makes use of the broadcast nature
of radio transmission to reduce the number of packets. We have integrated this
algorithm into TinyXXL, a programming language extension for data exchange.
This combined system offers seamless support both for data exchange among the
components of a single node and for efficient neighborhood data sharing. We
show that compared to existing solutions, such as Hood, our approach further
reduces the work of the application developer and provides greater efficiency.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-01&engl=0}
}
@article {ART-2007-17,
author = {Klaus Herrmann and Gero M{\"u}hl and Michael Jaeger},
title = {{MESHMdl Event Spaces -- A Coordination Middleware for Self-Organizing Applications in Ad hoc Networks}},
journal = {Journal on Pervasive and Mobile Computing - Special Issue on Middleware for Pervasive Computing},
publisher = {Elsevier Science Publishers B. V.},
volume = {3},
number = {4},
pages = {467--487},
type = {Artikel in Zeitschrift},
month = {August},
year = {2007},
issn = {1574-1192},
doi = {http://dx.doi.org/10.1016/j.pmcj.2007.04.003},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
contact = {Please contact me by a href=``mailto:klaus.herrmann@ipvs.uni-stuttgart.de?subject=Paper\%20inquiry''email if you need a copy of this article.},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Mobile ad hoc networks (MANETs) are gaining importance as a promising
technology for flexible, proximity-based, mobile communication. However, the
inherent dynamics of MANETs imposes strong limitations on the design of
distributed applications. They need to be able to adapt to changing conditions
quickly and organize themselves in terms of component placement and
communication habits. In this paper, we present MESHMdl, a middleware that
provides a high level of awareness and decoupling for application components to
make them more flexible and adaptable. We focus on the Event Space as the
central communication medium of MESHMdl. The Event Space offers a simple,
unified communication interface for inter-agent communication as well as for
communication with the middleware and resource access. Furthermore, it serves
as a means for flexibly extending a MESHMdl daemon. We investigate the
performance of the Event Space on different mobile devices and show that it is
superior to comparable systems.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2007-17&engl=0}
}
@article {ART-2007-11,
author = {Lorenzo Alvisi and Jeroen Doumen and Rachid Guerraoui and Boris Koldehofe and Harry Li and Robbert van Renesse and Gilles Tredan},
title = {{How robust are gossip-based communication protocols?}},
journal = {ACM SIGOPS Operating Systems Review},
address = {New York, NY, USA},
publisher = {ACM Press},
volume = {41},
number = {5},
pages = {14--18},
type = {Artikel in Zeitschrift},
month = {Oktober},
year = {2007},
doi = {10.1145/1317379.1317383},
issn = {0163-5980},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
D.2.4 Software Engineering Software/Program Verification},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Gossip-based communication protocols are often touted as being robust. Not
surprisingly, such a claim relies on assumptions under which gossip protocols
are supposed to operate. In this paper, we discuss and in some cases expose
some of these assumptions and discuss how sensitive the robustness of gossip is
to these assumptions. This analysis gives rise to a collection of new research
challenges.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2007-11&engl=0}
}
@article {ART-2007-02,
author = {Illya Stepanov and Kurt Rothermel},
title = {{Simulating mobile ad hoc networks in city scenarios}},
journal = {Computer Communications},
publisher = {Elsevier},
volume = {30},
number = {7},
pages = {1466--1475},
type = {Artikel in Zeitschrift},
month = {April},
year = {2007},
keywords = {Communication systems; Geographic information systems; Mobile communication; Modeling; Simulation},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.4 Performance of Systems,
I.6.3 Simulation and Modeling Applications},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Simulation tools are frequently used for the performance evaluations of mobile
ad hoc networks. Currently the tools do not take a spatial environment into
account, thus providing a poor support for urban scenarios. In this paper, we
describe a platform for the modeling of city scenarios. We extend the mostly
used MANET simulator ns-2 by the corresponding mobility and wireless
transmission models. These models have been evaluated against real-world
measurements. By using the tool’s emulation facility, we integrate unmodified
applications and real implementations of network protocols. We demonstrate the
usefulness of the platform by modeling a mobile application in a simulated
environment of Stuttgart downtown. We show that obtained simulation results
differ extensively from those with simpler models.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2007-02&engl=0}
}
@article {ART-2007-01,
author = {Steffen Maier and Daniel Herrscher and Kurt Rothermel},
title = {{Experiences with node virtualization for scalable network emulation}},
journal = {Computer Communications},
publisher = {Elsevier},
volume = {30},
number = {5},
pages = {943--956},
type = {Artikel in Zeitschrift},
month = {M{\"a}rz},
year = {2007},
keywords = {software performance evaluation; network emulation; mobile ad hoc network; scalability; virtual routing},
language = {Englisch},
cr-category = {C.4 Performance of Systems,
D.4.4 Operating Systems Communications Management,
D.4.8 Operating Systems Performance,
I.6.3 Simulation and Modeling Applications},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2007-01/ART-2007-01.pdf,
http://dx.doi.org/10.1016/j.comcom.2006.08.018},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {During the development of network protocols and distributed applications, their
performance has to be analyzed in appropriate environments. Network emulation
testbeds provide a synthetic, configurable network environment for comparative
performance measurements of real implementations. Realistic scenarios have to
consider hundreds of communicating nodes. Common network emulation approaches
limit the number of nodes in a scenario to the number of computers in an
emulation testbed. To overcome this limitation, we introduce a virtual node
concept for network emulation. The key problem for node virtualization is a
transparent, yet efficient separation of node resources. In this paper, we
provide a brief survey of candidate node virtualization approaches to
facilitate scalable network emulation. Based on the gathered insights, we
propose a lightweight virtualization solution to achieve maximum scalability
and discuss the main points regarding its implementation. We present extensive
evaluations that show the scalability and transparency of our approach in both
a traditional wired infrastructure-based, and in two wireless ad hoc network
emulation scenarios. The measurements indicate that our solution can push the
upper limit of emulation scenario sizes by a factor of 10--28. Given our
emulation testbed consisting of 64 computers, this translates to possible
scenario sizes of up to 1792 nodes. In addition to the evaluation of our
virtualization approach, we discuss key concepts for controlling comprehensive
emulation scenarios to support scalability of our system as a whole.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2007-01&engl=0}
}
@inbook {INBOOK-2007-04,
author = {Klaus Herrmann},
title = {{Selbstorganisierende Infrastrukturen f{\"u}r Ambient Services}},
series = {GI-Edition Lecture Notes in Informatics (LNI) - Ausgezeichnete Informatikdissertationen 2006},
publisher = {K{\"o}llen Verlag},
series = {GI-Edition Lecture Notes in Informatics (LNI)},
volume = {D-7},
pages = {109--118},
type = {Beitrag in Buch},
month = {Januar},
year = {2007},
keywords = {self-organization, replica placement, ambient intelligence, ambient services},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INBOOK-2007-04/INBOOK-2007-04.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Die Vision von intelligenten Umgebungen (Ambient Intelligence - AmI) als neues
Paradigma f{\"u}r die Unterst{\"u}tzung mobiler Benutzer bei allt{\"a}glichen T{\"a}tigkeiten
r{\"u}ckt derzeit zunehmend in den Fokus Europ{\"a}ischer Forschungsaktivit{\"a}ten. Ein
hoher Grad an Autonomie auf Seiten der unterst{\"u}tzenden Software-Systeme ist
hierf{\"u}r eine unabdingbare Voraussetzung. Derartige Systeme m{\"u}ssen in der Lage
sein, sich selbst ohne steuernde Eingriffe von Benutzern an deren Aktivit{\"a}ten
und Verhalten anzupassen. Entsprechende Systeme sind derzeit jedoch weitgehend
unerforscht. Diese Arbeit stellt den ersten umfassenden Ansatz f{\"u}r eine
selbstorganisierende Plattform zur Unterst{\"u}tzung von so genannten Ambient
Services dar - Diensten, die es dem mobilen Benutzer gestatten, mit seiner
unmittelbaren Umgebung zu interagieren. Diese als Ad hoc Service Grid (ASG)
bezeichnete Plattform kann spontan in beliebigen Umgebungen (z.B.
Einkaufszentren, Baustellen, Messen, etc.) eingesetzt werden, um dort
entsprechende Dienste anzubieten. In der Arbeit schlagen wir zun{\"a}chst ein
Modell f{\"u}r eine entsprechende Infrastruktur aus spontan vernetzten
Rechnerknoten vor. Diese ist modular aufgebaut und im Einsatz flexibel
erweiterbar. Der eigentliche Fokus liegt jedoch auf der Entwicklung und
Evaluierung einer Reihe von Basis-Algorithmen und Protokollen f{\"u}r das
selbstorganisierte Betreiben dieser Infrastruktur. Hier konzentrieren wir uns
auf die Platzierung von Ambient Service-Instanzen, deren Auffinden (Discovery
und Lookup), und auf die Erhaltung der Konsistenz einer Gruppe verteilt
laufender Replikate eines solchen Dienstes. Diese Mechanismen legen zusammen
eine essenzielle Grundlage f{\"u}r die Weiterentwicklung intelligenter Umgebungen.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2007-04&engl=0}
}
@inbook {INBOOK-2007-01,
author = {J{\"o}rg H{\"a}hner and Christian Becker and Pedro Jos{\'e} Marr{\'o}n and Kurt Rothermel},
title = {{Drahtlose Sensornetze - Fenster zur Realwelt}},
series = {Die Informatisierung des Alltags},
address = {Berlin, Heidelberg},
publisher = {Springer-Verlag},
pages = {41--60},
type = {Beitrag in Buch},
month = {Juli},
year = {2007},
isbn = {978-3-540-71454-5},
keywords = {Sensornetze; Datenverwaltung; Konsistenz},
language = {Deutsch},
cr-category = {C.2 Computer-Communication Networks,
H.2 Database Management},
ee = {http://dx.doi.org/10.1007/978-3-540-71455-2_4},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Sensornetze stellen eine technische L{\"o}sung f{\"u}r die Erfassung und Verarbeitung
von Informationen der physischen Welt dar. Dabei handelt es sich um eine Menge
sogenannter Sensorknoten, die — meist drahtlos — miteinander kommunizieren
k{\"o}nnen. Sensorknoten sind miniaturisierte Computer, die — neben einem
Mikroprozessor und einer Kommunikationsschnittstelle — mit Sensoren
ausgestattet sind. Diese Sensoren erlauben es, physikalische Gr{\"o}{\ss}en in der
Umgebung des Knotens zu messen. Mit Hilfe des Mikroprozessors k{\"o}nnen diese
Messwerte verarbeitet und {\"u}ber die Kommunikationsschnittstelle an andere
Sensorknoten verschickt werden. In diesem Beitrag werden zun{\"a}chst verschiedene
Einsatz-gebiete von Sensornetzen vorgestellt. Danach werden technische
Eigenschaften von Sensornetzen anhand exemplarischer Sensorknoten diskutiert.
Neue wissen-schaftliche Herausforderungen werden beispielhaft anhand des
Gebiets der Daten-verwaltung in Sensornetzen vorgestellt.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2007-01&engl=0}
}
