198,230 research outputs found
Platforms for Teaching Distributed Computing Concepts to Undergraduate Students
Over the last two decades, information technology has been moving towards distributed computing to host their applications and services. These systems can process more data more reliably than their central processing counterparts; however, distributed applications are more complex to design and develop because they require additional properties like replication and fault tolerance to work effectively. These complexities translate to the educational setting, where schools need to invest in additional infrastructure, knowledge, and technologies to teach distributed concepts to students.
This project presents the design and implementation of a complete educational framework for the teaching of distributed computing concepts at Cal Poly. The framework consists of three components: a Raspberry Pi cluster, a custom distributed file system (DecaFS), and a set of labs that can be used to support coursework in a distributed computing class. Each cluster is composed of five networked Raspberry Pi computers. The DecaFS distributed file system runs on the Raspberry Pi cluster. DecaFS provides the base functionality of a distributed file system with a design that allows for easy modification of sections of the implementation. The lab exercises focus on important distributed computing concepts that represent a variety of problems encountered in distributed systems including distribution, replication, fault tolerance, recovery, rebalancing, and efficiency. Isolation of the lab related modules allows students to focus on the learning objectives of the labs without needing to set up network and file system infrastructure to support the distributed aspects.
The complexities of teaching distributed computing concepts in a classroom setting at Cal Poly have been addressed with this project\u27s framework. The solution overcomes key educational challenges as it is portable, modular, scalable and affordable. The framework provides the ability to offer courses in distributed computing to better prepare students for the challenges presented in industry today. Through the use of a modular distributed file system and computing cluster that were created for this project, students are able to solve complex distributed problems, in the form of labs, in an isolated environment that is conducive to quarter long learning objectives. This work is a major step to bringing distributed computing into the classrooms at Cal Poly and classes are currently being designed around this curriculum. Cal Poly can evolve the framework to keep pace with the ever advancing information technology world so that it may continue to serve the needs of the faculty and students of Cal Poly
Intelligent monitoring and fault diagnosis for ATLAS TDAQ: a complex event processing solution
Effective monitoring and analysis tools are fundamental in modern IT
infrastructures to get insights on the overall system behavior and to deal
promptly and effectively with failures. In recent years, Complex Event
Processing (CEP) technologies have emerged as effective solutions for
information processing from the most disparate fields: from wireless sensor
networks to financial analysis. This thesis proposes an innovative approach to
monitor and operate complex and distributed computing systems, in particular
referring to the ATLAS Trigger and Data Acquisition (TDAQ) system currently
in use at the European Organization for Nuclear Research (CERN). The
result of this research, the AAL project, is currently used to provide ATLAS
data acquisition operators with automated error detection and intelligent
system analysis.
The thesis begins by describing the TDAQ system and the controlling
architecture, with a focus on the monitoring infrastructure and the expert
system used for error detection and automated recovery. It then discusses
the limitations of the current approach and how it can be improved to
maximize the ATLAS TDAQ operational efficiency.
Event processing methodologies are then laid out, with a focus on CEP
techniques for stream processing and pattern recognition. The open-source
Esper engine, the CEP solution adopted by the project is subsequently
analyzed and discussed.
Next, the AAL project is introduced as the automated and intelligent
monitoring solution developed as the result of this research. AAL
requirements and governing factors are listed, with a focus on how stream
processing functionalities can enhance the TDAQ monitoring experience. The
AAL processing model is then introduced and the architectural choices are
justified. Finally, real applications on TDAQ error detection are presented. The main conclusion from this work is that CEP techniques can be
successfully applied to detect error conditions and system misbehavior.
Moreover, the AAL project demonstrates a real application of CEP concepts
for intelligent monitoring in the demanding TDAQ scenario. The adoption of
AAL by several TDAQ communities shows that automation and intelligent
system analysis were not properly addressed in the previous infrastructure.
The results of this thesis will benefit researchers evaluating intelligent
monitoring techniques on large-scale distributed computing system
Designing Software Architectures As a Composition of Specializations of Knowledge Domains
This paper summarizes our experimental research and software development activities in designing robust, adaptable and reusable software architectures. Several years ago, based on our previous experiences in object-oriented software development, we made the following assumption: ‘A software architecture should be a composition of specializations of knowledge domains’. To verify this assumption we carried out three pilot projects. In addition to the application of some popular domain analysis techniques such as use cases, we identified the invariant compositional structures of the software architectures and the related knowledge domains. Knowledge domains define the boundaries of the adaptability and reusability capabilities of software systems. Next, knowledge domains were mapped to object-oriented concepts. We experienced that some aspects of knowledge could not be directly modeled in terms of object-oriented concepts. In this paper we describe our approach, the pilot projects, the experienced problems and the adopted solutions for realizing the software architectures. We conclude the paper with the lessons that we learned from this experience
Sparse Signal Processing Concepts for Efficient 5G System Design
As it becomes increasingly apparent that 4G will not be able to meet the
emerging demands of future mobile communication systems, the question what
could make up a 5G system, what are the crucial challenges and what are the key
drivers is part of intensive, ongoing discussions. Partly due to the advent of
compressive sensing, methods that can optimally exploit sparsity in signals
have received tremendous attention in recent years. In this paper we will
describe a variety of scenarios in which signal sparsity arises naturally in 5G
wireless systems. Signal sparsity and the associated rich collection of tools
and algorithms will thus be a viable source for innovation in 5G wireless
system design. We will discribe applications of this sparse signal processing
paradigm in MIMO random access, cloud radio access networks, compressive
channel-source network coding, and embedded security. We will also emphasize
important open problem that may arise in 5G system design, for which sparsity
will potentially play a key role in their solution.Comment: 18 pages, 5 figures, accepted for publication in IEEE Acces
Ontology-based collaborative framework for disaster recovery scenarios
This paper aims at designing of adaptive framework for supporting
collaborative work of different actors in public safety and disaster recovery
missions. In such scenarios, firemen and robots interact to each other to reach
a common goal; firemen team is equipped with smart devices and robots team is
supplied with communication technologies, and should carry on specific tasks.
Here, reliable connection is mandatory to ensure the interaction between
actors. But wireless access network and communication resources are vulnerable
in the event of a sudden unexpected change in the environment. Also, the
continuous change in the mission requirements such as inclusion/exclusion of
new actor, changing the actor's priority and the limitations of smart devices
need to be monitored. To perform dynamically in such case, the presented
framework is based on a generic multi-level modeling approach that ensures
adaptation handled by semantic modeling. Automated self-configuration is driven
by rule-based reconfiguration policies through ontology
Knowledge-infused and Consistent Complex Event Processing over Real-time and Persistent Streams
Emerging applications in Internet of Things (IoT) and Cyber-Physical Systems
(CPS) present novel challenges to Big Data platforms for performing online
analytics. Ubiquitous sensors from IoT deployments are able to generate data
streams at high velocity, that include information from a variety of domains,
and accumulate to large volumes on disk. Complex Event Processing (CEP) is
recognized as an important real-time computing paradigm for analyzing
continuous data streams. However, existing work on CEP is largely limited to
relational query processing, exposing two distinctive gaps for query
specification and execution: (1) infusing the relational query model with
higher level knowledge semantics, and (2) seamless query evaluation across
temporal spaces that span past, present and future events. These allow
accessible analytics over data streams having properties from different
disciplines, and help span the velocity (real-time) and volume (persistent)
dimensions. In this article, we introduce a Knowledge-infused CEP (X-CEP)
framework that provides domain-aware knowledge query constructs along with
temporal operators that allow end-to-end queries to span across real-time and
persistent streams. We translate this query model to efficient query execution
over online and offline data streams, proposing several optimizations to
mitigate the overheads introduced by evaluating semantic predicates and in
accessing high-volume historic data streams. The proposed X-CEP query model and
execution approaches are implemented in our prototype semantic CEP engine,
SCEPter. We validate our query model using domain-aware CEP queries from a
real-world Smart Power Grid application, and experimentally analyze the
benefits of our optimizations for executing these queries, using event streams
from a campus-microgrid IoT deployment.Comment: 34 pages, 16 figures, accepted in Future Generation Computer Systems,
October 27, 201
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