189 research outputs found
Software Platforms for Smart Cities: Concepts, Requirements, Challenges, and a Unified Reference Architecture
Making cities smarter help improve city services and increase citizens'
quality of life. Information and communication technologies (ICT) are
fundamental for progressing towards smarter city environments. Smart City
software platforms potentially support the development and integration of Smart
City applications. However, the ICT community must overcome current significant
technological and scientific challenges before these platforms can be widely
used. This paper surveys the state-of-the-art in software platforms for Smart
Cities. We analyzed 23 projects with respect to the most used enabling
technologies, as well as functional and non-functional requirements,
classifying them into four categories: Cyber-Physical Systems, Internet of
Things, Big Data, and Cloud Computing. Based on these results, we derived a
reference architecture to guide the development of next-generation software
platforms for Smart Cities. Finally, we enumerated the most frequently cited
open research challenges, and discussed future opportunities. This survey gives
important references for helping application developers, city managers, system
operators, end-users, and Smart City researchers to make project, investment,
and research decisions.Comment: Accepted for publication in ACM Computing Survey
Application live-upgrading and error-recovery using code-data decoupling
When applications have critical bugs that present security vulnerabilities or may result in serious failures with potential massive business level impact, these applications have to be updated as fast as possible to minimize the harm of the bug. However, mission-critical or other user-facing applications may maintain critical internal state that has to be serialized and restored during the update process introducing signi1cant cost and delay.
Instead of serializing the internal state we propose to implement applications in such a way that the application state is fully decoupled (e.g. in a different address space or shared memory segment) from the application logic. Such a decoupling allows for example that upgrades can happen without serialization of the data, even allowing side-by-side execution of the updated and the failing version of the application and thereby reducing application downtime during the update process. Furthermore, this decoupling also allows applications to recover easily from failures by recovering the previous data of the crashed application instance
SHIELD: Sustainable Hybrid Evolutionary Learning Framework for Carbon, Wastewater, and Energy-Aware Data Center Management
Today's cloud data centers are often distributed geographically to provide
robust data services. But these geo-distributed data centers (GDDCs) have a
significant associated environmental impact due to their increasing carbon
emissions and water usage, which needs to be curtailed. Moreover, the energy
costs of operating these data centers continue to rise. This paper proposes a
novel framework to co-optimize carbon emissions, water footprint, and energy
costs of GDDCs, using a hybrid workload management framework called SHIELD that
integrates machine learning guided local search with a decomposition-based
evolutionary algorithm. Our framework considers geographical factors and
time-based differences in power generation/use, costs, and environmental
impacts to intelligently manage workload distribution across GDDCs and data
center operation. Experimental results show that SHIELD can realize 34.4x
speedup and 2.1x improvement in Pareto Hypervolume while reducing the carbon
footprint by up to 3.7x, water footprint by up to 1.8x, energy costs by up to
1.3x, and a cumulative improvement across all objectives (carbon, water, cost)
of up to 4.8x compared to the state-of-the-art
MOSAIC: A Multi-Objective Optimization Framework for Sustainable Datacenter Management
In recent years, cloud service providers have been building and hosting
datacenters across multiple geographical locations to provide robust services.
However, the geographical distribution of datacenters introduces growing
pressure to both local and global environments, particularly when it comes to
water usage and carbon emissions. Unfortunately, efforts to reduce the
environmental impact of such datacenters often lead to an increase in the cost
of datacenter operations. To co-optimize the energy cost, carbon emissions, and
water footprint of datacenter operation from a global perspective, we propose a
novel framework for multi-objective sustainable datacenter management (MOSAIC)
that integrates adaptive local search with a collaborative decomposition-based
evolutionary algorithm to intelligently manage geographical workload
distribution and datacenter operations. Our framework sustainably allocates
workloads to datacenters while taking into account multiple geography- and
time-based factors including renewable energy sources, variable energy costs,
power usage efficiency, carbon factors, and water intensity in energy. Our
experimental results show that, compared to the best-known prior work
frameworks, MOSAIC can achieve 27.45x speedup and 1.53x improvement in Pareto
Hypervolume while reducing the carbon footprint by up to 1.33x, water footprint
by up to 3.09x, and energy costs by up to 1.40x. In the simultaneous
three-objective co-optimization scenario, MOSAIC achieves a cumulative
improvement across all objectives (carbon, water, cost) of up to 4.61x compared
to the state-of-the-arts
KYPO: A Tool for Collaborative Study of Cyberattacks in Safe Cloud Environment
This paper introduces the KYPO -- a cloud-based virtual environment faithfully simulating real networks and enabling users to study cyber attacks as well as to train users in isolated and controlled environment. Particularly, the paper focuses on the user environment and visualizations, providing views and interactions improving the understanding of processes emerged during experiments. Web user interface of the KYPO system supports several collaboration modes enabling the participants to experiment and replay different types of security related tasks
Innovation Mashups: Academic Rigor Meets Social Networking Buzz
Exploring new options for publishing and content delivery offers an enormous opportunity to improve the state of the art and further modernize academic and professional publications.
Traditional organizations such as the IEEE Computer Society, ACM, and Usenix have been encountering increasing competition from new ways of rapid publishing and dissemination, including social networking sites (Facebook, Twitter, LinkedIn, Google+), blogs with enabled commenting, video posting (YouTube), Slashdot, and many other types of media. Liking is replacing traditional impact factors, comments left on authors\u27 webpages or blogs are replacing formal reviews, and site visits have more relevance than the number of article citations
Heterogeneous Strong Computation Migration
The continuous increase in performance requirements, for both scientific
computation and industry, motivates the need of a powerful computing
infrastructure. The Grid appeared as a solution for inexpensive execution of
heavy applications in a parallel and distributed manner. It allows combining
resources independently of their physical location and architecture to form a
global resource pool available to all grid users. However, grid environments
are highly unstable and unpredictable. Adaptability is a crucial issue in this
context, in order to guarantee an appropriate quality of service to users.
Migration is a technique frequently used for achieving adaptation. The
objective of this report is to survey the problem of strong migration in
heterogeneous environments like the grids', the related implementation issues
and the current solutions.Comment: This is the pre-peer reviewed version of the following article:
Milan\'es, A., Rodriguez, N. and Schulze, B. (2008), State of the art in
heterogeneous strong migration of computations. Concurrency and Computation:
Practice and Experience, 20: 1485-1508, which has been published in final
form at http://onlinelibrary.wiley.com/doi/10.1002/cpe.1287/abstrac
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