84 research outputs found
Quality-of-service management in IP networks
Quality of Service (QoS) in Internet Protocol (IF) Networks has been the subject of
active research over the past two decades. Integrated Services (IntServ) and
Differentiated Services (DiffServ) QoS architectures have emerged as proposed
standards for resource allocation in IF Networks. These two QoS architectures
support the need for multiple traffic queuing systems to allow for resource
partitioning for heterogeneous applications making use of the networks. There have
been a number of specifications or proposals for the number of traffic queuing
classes (Class of Service (CoS)) that will support integrated services in IF Networks,
but none has provided verification in the form of analytical or empirical investigation
to prove that its specification or proposal will be optimum.
Despite the existence of the two standard QoS architectures and the large volume of
research work that has been carried out on IF QoS, its deployment still remains
elusive in the Internet. This is not unconnected with the complexities associated with
some aspects of the standard QoS architectures. [Continues.
Scratchpad Memory Management For Multicore Real-Time Embedded Systems
Multicore systems will continue to spread in the domain of real-time embedded systems due to the increasing need for high-performance applications. This research discusses some of the challenges associated with employing multicore systems for safety-critical real-time applications. Mainly, this work is concerned with providing: 1) efficient inter-core timing isolation for independent tasks, and 2) predictable task communication for communicating tasks.
Principally, we introduce a new task execution model, based on the 3-phase execution model, that exploits the Direct Memory Access (DMA) controllers available in modern embedded platforms along with ScratchPad Memories (SPMs) to enforce strong timing isolation between tasks. The DMA and the SPMs are explicitly managed to pre-load tasks from main memory into the local (private) scratchpad memories. Tasks are then executed from the local SPMs without accessing main memory. This model allows CPU execution to be overlapped with DMA loading/unloading operations from and to main memory. We show that by co-scheduling task execution on CPUs and using DMA to access memory and I/O, we can efficiently hide access latency to physical resources. In turn, this leads to significant improvements in system schedulability, compared to both the case of unregulated contention for access to physical resources and to previous cache and SPM management techniques for real-time systems.
The presented SPM-centric scheduling algorithms and analyses cover single-core, partitioned, and global real-time systems. The proposed scheme is also extended to support large tasks that do not fit entirely into the local SPM. Moreover, the schedulability analysis considers the case of recovering from transient soft errors (bit flips caused by a single event upset) in several levels of memories, that cannot be automatically corrected in hardware by the ECC unit. The proposed SPM-centric scheduling is integrated at the OS level; thus it is transparent to applications. The proposed scheme is implemented and evaluated on an FPGA platform and a Commercial-Off-The-Shelf (COTS) platform.
In regards to real-time task communication, two types of communication are considered. 1) Asynchronous inter-task communication, between either sequential tasks (single-threaded) or parallel tasks (multi-threaded). 2) Intra-task communication, where parallel threads of the same application exchange data. A new task scheduling model for parallel tasks (Bundled Scheduling) is proposed to facilitate intra-task communication and reduce synchronization overheads. We show that the proposed bundled scheduling model can be applied to several parallel programming models, such as fork-join and DAG-based applications, leading to improved system schedulability. Finally, intra-task communication is governed by a predictable inter-core communication platform. Specifically, we propose HopliteRT, a lean and predictable Network-on-Chip that connects the private SPMs
Mobile Ad-Hoc Networks
Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of-the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: quality-of-service and video communication, routing protocol and cross-layer design. A few interesting problems about security and delay-tolerant networks are also discussed. This book is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks
2016 Oklahoma Research Day Full Program
This document contains all abstracts from the 2016 Oklahoma Research Day held at Northeastern State University
Machine Learning
Machine Learning can be defined in various ways related to a scientific domain concerned with the design and development of theoretical and implementation tools that allow building systems with some Human Like intelligent behavior. Machine learning addresses more specifically the ability to improve automatically through experience
IT\u27S NOT RAINBOWS AND UNICORNS : REGULATED COMMODITY AND WASTE PRODUCTION IN THE ALBERTA OILSANDS
This dissertation examines the regulated oilsands mining industry of Alberta, Canada, widely considered the worldâs largest surface mining project. The industrial processes of oilsands mining produce well over one million barrels of petroleum commodities daily, plus even larger quantities of airborne and semisolid waste. The project argues for a critical account of production concretized in the co-constitutional relations of obdurate materiality and labor activity within a framework of regulated petro-capitalism. This pursuit requires multiple methods that combine archives, participant observation, and semi-structured interviews to understand workersâ shift-to-shift relations inside the âblack boxâ of regulated oilsands mining production where materiality co-constitutes the processes and outcomes of resource development and waste-intensive production. Here, the central contradiction pits the industryâs colossal environmental impact and its regulated environmental relations, which â despite chronic exceedances â are held under some control by provincial and federal environmental agents, further attenuated by firmsâ selective voluntary compliance with global quality standards as well as whistleblowers and otherwise âtroublesomeâ employees. âItâs not rainbows and unicorns,â explains one informant, distilling workersâ views of the safety and environmental hazards they simultaneously produce and endure as wage laborers despite pervasive regulation. In addition to buttressing geographical conceptualizations of socionatural resource production, contributions arise in the sympathetic engagement with workers, which may hold useful insights for activism against the industryâs environmental outcomes
Play Among Books
How does coding change the way we think about architecture? Miro Roman and his AI Alice_ch3n81 develop a playful scenario in which they propose coding as the new literacy of information. They convey knowledge in the form of a project model that links the fields of architecture and information through two interwoven narrative strands in an âinfinite flowâ of real books
Forwarding on Gates: A flexible and scalable inter-network layer supporting in-network functions
How to design an inter-network that is flexible regarding its features and scalable at the same time? How can such an inter-network satisfy requirements from applications and subnetworks dynamically? Can routing be more flexible and balance the wishes from end user and network operators? Is there a better world beyond current IP-networks?
This book answers these questions by presenting a new architecture called "Forwarding on Gates" (FoG). It exploits the advantages of a recursive reference model and does not follow the traditional OSI reference model. FoG mixes connection-oriented and connectionless aspects dynamically in order to increase its efficiency. It enables a scalable function provisioning by a flexible distribution of states between network participants. Its routing can adjust itself to an optimal trade-off between CPU and memory usage. Moreover, FoG supports new business cases and opens up a market for network-related functions, at which function provider can offer their functions to function users.Auch im Buchhandel erhÀltlich:
Forwarding on Gates : a flexible and scalable inter-network layer supporting in-network functions / Florian Liers
Ilmenau : Univ.-Verl. Ilmenau, 2014. - XII, 258 S.
ISBN 978-3-86360-094-5
URN urn:nbn:de:gbv:ilm1-2013000657
Preis (Druckausgabe): 30,80
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