@inproceedings {INPROC-2016-34,
author = {Florian Berg and Frank D{\"u}rr and Kurt Rothermel},
title = {{Increasing the Efficiency of Code Offloading in n-tier Environments with Code Bubbling}},
booktitle = {Proceedings of the 13th Annual International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services},
publisher = {-},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
type = {Konferenz-Beitrag},
month = {November},
year = {2016},
isbn = {978-1-4503-4750-1/16/11},
doi = {dx.doi.org/10.1145/2994374.2994375},
keywords = {Mobile Cloud Computing; Multi-tier Code Offloading; Cyber Foraging; Code Bubbling; n-tier environment},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
contact = {Florian.Berg@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Code offloading strives for increasing the energy efficiency and execution
speed of mobile applications on resource-constrained mobile devices. First
approaches considered only a code offloading between two (or three) tiers,
executing code either locally on the mobile device or remotely on a powerful
server in the vicinity or in a distant cloud. However, new execution
environments comprise multiple tiers, containing highly distributed
heterogeneous resources. We present in this paper our Code Bubbling Offload
System (CoBOS). CoBOS targets n-tier environments containing highly distributed
heterogeneous resources with different performance characteristics and cost
implications. In such n-tier environments, it is very costly for a
resource-constrained mobile device to gather a global view on available
resources. As a result, we propose the novel concept of code bubbling. Code
bubbling moves code dynamically and adaptively towards more powerful and more
distant tiers, enabling an efficient and scalable code offloading in n-tier
environments. Each tier makes autonomous decisions to execute code in the tier
or forward it further to the next tier. To support such a recursive escalation
of code along autonomous tiers, CoBOS offloads self-contained offload requests
that possess all of the required information for the processing. Our real-world
evaluation shows that CoBOS decreases the energy consumption by 77\% and the
execution time by 83\% for code offloading in n-tier environments.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2016-34&engl=0}
}
@inproceedings {INPROC-2015-48,
author = {Florian Berg and Frank D{\"u}rr and Kurt Rothermel},
title = {{Increasing the Efficiency of Code Offloading through Remote-side Caching}},
booktitle = {Proceedings of the IEEE 11th International Conference on Wireless and Mobile Computing, Networking and Communications: WiMob'15; Abu-Dhabi, United Arab Emirates (UAE), October 19-21, 2015},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {573--580},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2015},
doi = {10.1109/WiMOB.2015.7348013},
keywords = {Mobile Cloud Computing; Code Offloading; Distributed Execution; Data Replication; Function Caching},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {http://dx.doi.org/10.1109/WiMOB.2015.7348013},
contact = {Florian.Berg@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {End users execute today on their smart phones different kinds of mobile
applications like calendar apps or high-end mobile games, differing in local
resource usage. Utilizing local resources of a smart phone heavily, like
playing high-end mobile games, drains its limited energy resource in few hours.
To prevent the limited energy resource from a quick exhaustion, smart phones
benefit from executing resource-intensive application parts on a remote server
in the cloud (code offloading). During the remote execution on the remote
server, a smart phone waits in idle mode until it receives a result. However,
code offloading introduces computation and communication overhead, which
decreases the energy efficiency and induces monetary cost. For instance,
sending or receiving execution state information to or from a remote server
consumes energy. Moreover, executing code on a remote server instance in a
commercial cloud causes monetary cost. To keep consumed energy and monetary
cost low, we present in this paper the concept of remote-side caching for code
offloading, which increases the efficiency of code offloading. The remote-side
cache serves as a collective storage of results for already executed
application parts on remote servers, avoiding the repeated execution of
previously run application parts. The smart phone queries the remote-side cache
for corresponding results of resource-intensive application parts. In case of a
cache hit, the smart phone gets immediately a result and continues the
application execution. Otherwise, it migrates the application part and waits
for a result of the remote execution. We show in our evaluation that the use of
a remote-side cache decreases energy consumption and monetary cost for mobile
applications by up to 97\% and 99\%, respectively.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2015-48&engl=0}
}
@inproceedings {INPROC-2014-78,
author = {Florian Berg and Frank D{\"u}rr and Kurt Rothermel},
title = {{Optimal Predictive Code Offloading}},
booktitle = {Proceedings of the 11th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--10},
type = {Konferenz-Beitrag},
month = {Dezember},
year = {2014},
doi = {10.4108/icst.mobiquitous.2014.258023},
keywords = {Code Offloading; Markov chain; Link quality},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {http://dl.acm.org/citation.cfm?id=2692985},
contact = {Florian.Berg@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Modern mobile devices like smart phones and tablets are equipped with powerful
processing and memory resources, enabling resource-intensive mobile
applications such as high-end mobile games. The main limitation, however,
remains the energy resource. To improve the energy efficiency, code offloading
has been proposed, which offloads code to remote servers and transfers the
results back to the mobile device. Although several approaches have shown that
code offloading improves energy efficiency significantly in general, they
largely neglect the adverse effects of network disconnections. Therefore, we
have proposed the concept of preemptive code offloading to improve energy
efficiency also under link failures. It transmits so-called safe-points between
server and mobile device during remote execution, enabling the re-use of
partial remote results after link failures. In this paper, we improve our basic
preemptive code offloading approach by optimizing the time when to generate and
transmit safe-points to minimize the communication overhead and maximize energy
efficiency. To find the optimal safe-point schedule, we use a predictive
approach that predicts the mobile link quality in order to send safe-points
before network disconnections. Moreover, we consider additional deadline
constraints for code execution to ensure a minimal responsiveness of offloaded
applications despite link failures. Our evaluation results show that energy
efficiency can be improved significantly using our predictive offloading
approach.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2014-78&engl=0}
}
@inproceedings {INPROC-2014-32,
author = {Florian Berg and Frank D{\"u}rr and Kurt Rothermel},
title = {{Increasing the Efficiency and Responsiveness of Mobile Applications with Preemptable Code Offloading}},
booktitle = {Proceedings of the 3rd IEEE International Conference on Mobile Services: MS'14; Anchorage, Alaska, USA, June 27 - July 2, 2014},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {76--83},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2014},
doi = {10.1109/MobServ.2014.20},
keywords = {Distributed Systems, Code Offloading, Safe-points, Mobile Cloud Computing, Efficiency, Responsiveness},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2014-32/INPROC-2014-32.pdf,
http://dx.doi.org/10.1109/MobServ.2014.20},
contact = {Florian.Berg@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Mobile applications are getting more and more sophisticated and demanding.
Although the processing, memory, and storage resources of mobile devices are
constantly increasing to enable such resource-demanding mobile applications,
battery capacity is still the main limiting factor. To solve this problem,
mobile code offloading approaches can be used to offload parts of a mobile
application to remote servers and utilize the resources of cloud services. In
this paper, we propose a novel code offloading approach that makes code
offloading robust against communication link failures, which are still a major
problem of mobile systems. To this end, we propose preemptable code offloading.
It allows for interrupting the offloading process and continuing the remote
execution locally after a link failure, without abandoning the complete result
calculated remotely so far. The basic idea of our approach is to create
safe-points of the remote execution and transmit these intermediate results
back to the mobile device. After a link failure, the mobile device can now
continue execution from the last transmitted safe-point. Although safe-points
induce communication and energy overhead, our evaluations show that using an
optimized safe-point schedule this overhead quickly pays off under link
failures. Besides reducing the overall energy consumption significantly,
responsiveness also benefits from safe-points by meeting given execution
deadlines after link failures.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2014-32&engl=0}
}
@inproceedings {INPROC-2012-13,
author = {Stefan F{\"o}ll and Florian Berg and Klaus Herrmann and Kurt Rothermel},
title = {{A Predictive Protocol for Mobile Context Updates with Hard Energy Constraints}},
booktitle = {Proceedings of the 13th International Conference on Mobile Data Management (MDM 2012)},
address = {Bengaluru, India},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {125--130},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2012},
doi = {10.1109/MDM.2012.11},
keywords = {mobile users; update protocols; discrete context; energy efficiency; context accuracy; contrained optimization problem, Markov decision process},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.4 Distributed Systems},
ee = {http://dx.doi.org/10.1109/MDM.2012.11},
contact = {stefan.foell@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {As mobile devices have become powerful sensor platforms, new applications have
emerged which continuously stream mobile user context (location, activities,
etc.). However, energy is a limited resource on battery-equipped mobile
devices. Especially frequent transmissions of context updates over
energy-expensive wireless channels drain the battery of mobile devices in an
uncontrolled manner. It is a fundamental algorithmic challenge to design
protocols such that users can control the energy consumption on mobile devices
while, at the same time, optimizing the quality of mobile applications. To
address this trade-off in the area of context update protocols, we propose a
novel protocol that maximizes the context accuracy perceived by a remote
consumer while guaranteeing that the consumed energy stays under a given limit.
Our update protocol exploits predictions about a user's future behaviour to
give priority to the most effective context updates. In our evaluation, we
apply our predictive update protocol to a real-world trace of user context and
show that the context accuracy is significantly increased compared to an update
protocol which operates without predictions under the same energy budget.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2012-13&engl=0}
}