28 research outputs found

    Software-Driven and Virtualized Architectures for Scalable 5G Networks

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    In this dissertation, we argue that it is essential to rearchitect 4G cellular core networks–sitting between the Internet and the radio access network–to meet the scalability, performance, and flexibility requirements of 5G networks. Today, there is a growing consensus among operators and research community that software-defined networking (SDN), network function virtualization (NFV), and mobile edge computing (MEC) paradigms will be the key ingredients of the next-generation cellular networks. Motivated by these trends, we design and optimize three core network architectures, SoftMoW, SoftBox, and SkyCore, for different network scales, objectives, and conditions. SoftMoW provides global control over nationwide core networks with the ultimate goal of enabling new routing and mobility optimizations. SoftBox attempts to enhance policy enforcement in statewide core networks to enable low-latency, signaling-efficient, and customized services for mobile devices. Sky- Core is aimed at realizing a compact core network for citywide UAV-based radio networks that are going to serve first responders in the future. Network slicing techniques make it possible to deploy these solutions on the same infrastructure in parallel. To better support mobility and provide verifiable security, these architectures can use an addressing scheme that separates network locations and identities with self-certifying, flat and non-aggregatable address components. To benefit the proposed architectures, we designed a high-speed and memory-efficient router, called Caesar, for this type of addressing schemePHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/146130/1/moradi_1.pd

    Internet connection method for mobile ad hoc wireless networks

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    In recent years, wireless networks with Internet services have become more and more popular. Technologies which integrate Internet and wireless networks have extended traditional Internet applications into a more flexible and dynamic environment. This research work investigates the technology that supports the connection between a Mobile Ad Hoc Wireless Network (MANET) and the Internet, which enables the current wireless Internet technologies to provide a ubiquitous wireless life style. With detailed analysis of the existing wireless Internet technologies and MANETs regarding their features and applications, the demand and lack of research work for an application to provide Internet connection to MANET is indicated. The primary difficulty for MANET and Internet connection is that the dynamic features of MANET do not suit the traditional connection methods used in infrastructure wireless networks. This thesis introduces new concept of the 'Gateway Awareness' (GAW) to the wireless devices in the MANET. GAW is a new routing protocol designed by the author of this thesis, at the University of Warwick. Based on GAW, an inclusive definition for the connection method, which supports the Internet connection and keeps the independency of routing in MANET, is addressed. Unlike other research work, this method supports the MANET and Internet communication in both directions. Furthermore, it explores possible ways of using the Internet as an extension for wireless communications. The GAW routing method is developed from destination sequenced distance vector (DSDV) routing protocol. However, it defines a layer of wireless nodes (known as GAWNs) with exclusive functions for the Internet connection task. The layer of GAWNs brings a new set of route update and route selection method. Simulations show that the GAW routing method provides quality Internet connection performance in different scenarios compared with other methods. In particular, the connection is completed with minimum effect on the independent MANET while the routing efficiency and accuracy is guaranteed

    Scientific Programming and Computer Architecture

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    A variety of programming models relevant to scientists explained, with an emphasis on how programming constructs map to parts of the computer.What makes computer programs fast or slow? To answer this question, we have to get behind the abstractions of programming languages and look at how a computer really works. This book examines and explains a variety of scientific programming models (programming models relevant to scientists) with an emphasis on how programming constructs map to different parts of the computer's architecture. Two themes emerge: program speed and program modularity. Throughout this book, the premise is to "get under the hood," and the discussion is tied to specific programs. The book digs into linkers, compilers, operating systems, and computer architecture to understand how the different parts of the computer interact with programs. It begins with a review of C/C++ and explanations of how libraries, linkers, and Makefiles work. Programming models covered include Pthreads, OpenMP, MPI, TCP/IP, and CUDA.The emphasis on how computers work leads the reader into computer architecture and occasionally into the operating system kernel. The operating system studied is Linux, the preferred platform for scientific computing. Linux is also open source, which allows users to peer into its inner workings. A brief appendix provides a useful table of machines used to time programs. The book's website (https://github.com/divakarvi/bk-spca) has all the programs described in the book as well as a link to the html text

    “INDUSTRIAL LEGISLATURES”: CONSENSUS STANDARDIZATION IN THE SECOND AND THIRD INDUSTRIAL REVOLUTIONS

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    Consensus standardization is a social process in which technical experts from public, private, and non-profit sectors negotiate the direction and shape of technological change. Scholars in a variety of disciplines have recognized the importance of consensus standards as alternatives to standards that arise through market mechanisms or standards mandated by regulators. Rather than treating the consensus method as some sort of timeless organizational form or ever-present alternative to markets or laws, I argue that consensus standardization is itself a product of history. In the first two chapters, I explain the origins and growth of consensus standards bodies between 1880 and 1930 as a reaction to and critique of the existing political economy of engineering. By considering the standardization process—instead of the internal dynamics of a particular firm or technology—as the primary category of analysis, I am able to emphasize the cooperative relations that sustained the American style of competitive managerial capitalism during the Second Industrial Revolution. In the remaining four chapters, I examine the processes of network architecture and standardization in the creation of four communications networks during the twentieth century: AT&T’s monopoly telephone network, the Internet, digital cellular telephone networks, and the World Wide Web. Each of these four networks embodied critiques—always implicit and frequently explicit—of preceding and competing networks. These critiques, visible both in the technological design of networks as well as in the institutional design of standard-setting bodies, reflected the political convictions of successive generations of engineers and network architects. The networks described in this dissertation were thus turning points in the century-long development of an organizational form. Seen as part of a common history, they tell the story of how consensus-based institutions became the dominant mode for setting standards in the Third Industrial Revolution, and created the foundational standards of the information infrastructures upon which a newly globalized economy and society—the Network Society—could grow

    The Missing Link: An Introduction to Web Development and Programming

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    Web development is an evolving amalgamation of languages that work in concert to receive, modify, and deliver information between parties using the Internet as a mechanism of delivery.While it is easy to describe conceptually, implementation is accompanied by an overwhelming variety of languages, platforms, templates, frameworks, guidelines, and standards. Navigating a project from concept to completion often requires more than mastery of one or two complementing languages, meaning today’s developers need both breadth, and depth, of knowledge to be effective. This text provides the developer with an understanding of the various elements of web development by focusing on the concepts and fundamentals through the examples within, providing a foundation that allows easier transition to other languages and a better understanding of how to approach their work. The reader will be introduced to topics in a manner that follows most project development methods, from initial conceptualization and design through front end development, back end development, and introducing additional concepts like accessibility and security, while focusing on responsive design techniques. Each section of the text includes opportunities to practice the material and assess increased knowledge after examining the topics.https://knightscholar.geneseo.edu/oer-ost/1016/thumbnail.jp

    Internet connection method for mobile ad hoc wireless networks

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    In recent years, wireless networks with Internet services have become more and more popular. Technologies which integrate Internet and wireless networks have extended traditional Internet applications into a more flexible and dynamic environment. This research work investigates the technology that supports the connection between a Mobile Ad Hoc Wireless Network (MANET) and the Internet, which enables the current wireless Internet technologies to provide a ubiquitous wireless life style. With detailed analysis of the existing wireless Internet technologies and MANETs regarding their features and applications, the demand and lack of research work for an application to provide Internet connection to MANET is indicated. The primary difficulty for MANET and Internet connection is that the dynamic features of MANET do not suit the traditional connection methods used in infrastructure wireless networks. This thesis introduces new concept of the 'Gateway Awareness' (GAW) to the wireless devices in the MANET. GAW is a new routing protocol designed by the author of this thesis, at the University of Warwick. Based on GAW, an inclusive definition for the connection method, which supports the Internet connection and keeps the independency of routing in MANET, is addressed. Unlike other research work, this method supports the MANET and Internet communication in both directions. Furthermore, it explores possible ways of using the Internet as an extension for wireless communications. The GAW routing method is developed from destination sequenced distance vector (DSDV) routing protocol. However, it defines a layer of wireless nodes (known as GAWNs) with exclusive functions for the Internet connection task. The layer of GAWNs brings a new set of route update and route selection method. Simulations show that the GAW routing method provides quality Internet connection performance in different scenarios compared with other methods. In particular, the connection is completed with minimum effect on the independent MANET while the routing efficiency and accuracy is guaranteed.EThOS - Electronic Theses Online ServiceUniversities UKUniversity of WarwickGBUnited Kingdo

    From diversity to convergence : British computer networks and the Internet, 1970-1995

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    The Internet's success in the 21st century has encouraged analysts to investigate the origin of this network. Much of this literature adopts a teleological approach. Works often begin by discussing the invention of packet switching, describe the design and development of the ARPANET, and then examine how this network evolved into the Internet. Although the ARPANET was a seminal computer network, these accounts usually only briefly consider the many other diverse networks that existed. In addition, apart from momentary asides to alternative internetworking solutions, such as the Open Systems Interconnection (OSI) seven-layer reference model, this literature concentrates exclusively on the ARPANET, the Internet, and the World Wide Web. While focusing on these subjects is important and therefore justified, it can leave the reader with the impression that the world of networking started with the ARPANET and ended with the Internet. This thesis is an attempt to help correct this misconception. This thesis analyses the evolution of British computer networks and the Internet between the years 1970 and 1995. After an introduction in Chapter 1, the thesis analyses several networks. In Chapters 2 and 3, the focus is on academic networks, especially JANET and SuperJANET. Attention moves to videotex networks in Chapter 4, specifically Prestel, and in Chapter 5, the dissertation examines electronic mail networks such as Telecom Gold and Cable & Wireless Easylink. Chapter 6 considers online services, including CompuServe, American Online, and the Microsoft Network, and the thesis ends with a conclusion in Chapter 7. All of the networks discussed used protocols that were incompatible with each other which limited the utility of the networks for their users. Although it was possible that OSI or another solution could have solved this problem, the Internet's protocols achieved this objective. This thesis shows how the networks converged around TCP/IP

    Semantic search and composition in unstructured peer-to-peer networks

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    This dissertation focuses on several research questions in the area of semantic search and composition in unstructured peer-to-peer (P2P) networks. Going beyond the state of the art, the proposed semantic-based search strategy S2P2P offers a novel path-suggestion based query routing mechanism, providing a reasonable tradeoff between search performance and network traffic overhead. In addition, the first semantic-based data replication scheme DSDR is proposed. It enables peers to use semantic information to select replica numbers and target peers to address predicted future demands. With DSDR, k-random search can achieve better precision and recall than it can with a near-optimal non-semantic replication strategy. Further, this thesis introduces a functional automatic semantic service composition method, SPSC. Distinctively, it enables peers to jointly compose complex workflows with high cumulative recall but low network traffic overhead, using heuristic-based bidirectional haining and service memorization mechanisms. Its query branching method helps to handle dead-ends in a pruned search space. SPSC is proved to be sound and a lower bound of is completeness is given. Finally, this thesis presents iRep3D for semantic-index based 3D scene selection in P2P search. Its efficient retrieval scales to answer hybrid queries involving conceptual, functional and geometric aspects. iRep3D outperforms previous representative efforts in terms of search precision and efficiency.Diese Dissertation bearbeitet Forschungsfragen zur semantischen Suche und Komposition in unstrukturierten Peer-to-Peer Netzen(P2P). Die semantische Suchstrategie S2P2P verwendet eine neuartige Methode zur Anfrageweiterleitung basierend auf Pfadvorschlägen, welche den Stand der Wissenschaft übertrifft. Sie bietet angemessene Balance zwischen Suchleistung und Kommunikationsbelastung im Netzwerk. Außerdem wird das erste semantische System zur Datenreplikation genannt DSDR vorgestellt, welche semantische Informationen berücksichtigt vorhergesagten zukünftigen Bedarf optimal im P2P zu decken. Hierdurch erzielt k-random-Suche bessere Präzision und Ausbeute als mit nahezu optimaler nicht-semantischer Replikation. SPSC, ein automatisches Verfahren zur funktional korrekten Komposition semantischer Dienste, ermöglicht es Peers, gemeinsam komplexe Ablaufpläne zu komponieren. Mechanismen zur heuristischen bidirektionalen Verkettung und Rückstellung von Diensten ermöglichen hohe Ausbeute bei geringer Belastung des Netzes. Eine Methode zur Anfrageverzweigung vermeidet das Feststecken in Sackgassen im beschnittenen Suchraum. Beweise zur Korrektheit und unteren Schranke der Vollständigkeit von SPSC sind gegeben. iRep3D ist ein neuer semantischer Selektionsmechanismus für 3D-Modelle in P2P. iRep3D beantwortet effizient hybride Anfragen unter Berücksichtigung konzeptioneller, funktionaler und geometrischer Aspekte. Der Ansatz übertrifft vorherige Arbeiten bezüglich Präzision und Effizienz

    From diversity to convergence : British computer networks and the Internet, 1970-1995

    Get PDF
    The Internet's success in the 21st century has encouraged analysts to investigate the origin of this network. Much of this literature adopts a teleological approach. Works often begin by discussing the invention of packet switching, describe the design and development of the ARPANET, and then examine how this network evolved into the Internet. Although the ARPANET was a seminal computer network, these accounts usually only briefly consider the many other diverse networks that existed. In addition, apart from momentary asides to alternative internetworking solutions, such as the Open Systems Interconnection (OSI) seven-layer reference model, this literature concentrates exclusively on the ARPANET, the Internet, and the World Wide Web. While focusing on these subjects is important and therefore justified, it can leave the reader with the impression that the world of networking started with the ARPANET and ended with the Internet. This thesis is an attempt to help correct this misconception. This thesis analyses the evolution of British computer networks and the Internet between the years 1970 and 1995. After an introduction in Chapter 1, the thesis analyses several networks. In Chapters 2 and 3, the focus is on academic networks, especially JANET and SuperJANET. Attention moves to videotex networks in Chapter 4, specifically Prestel, and in Chapter 5, the dissertation examines electronic mail networks such as Telecom Gold and Cable & Wireless Easylink. Chapter 6 considers online services, including CompuServe, American Online, and the Microsoft Network, and the thesis ends with a conclusion in Chapter 7. All of the networks discussed used protocols that were incompatible with each other which limited the utility of the networks for their users. Although it was possible that OSI or another solution could have solved this problem, the Internet's protocols achieved this objective. This thesis shows how the networks converged around TCP/IP.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Semantic search and composition in unstructured peer-to-peer networks

    Get PDF
    This dissertation focuses on several research questions in the area of semantic search and composition in unstructured peer-to-peer (P2P) networks. Going beyond the state of the art, the proposed semantic-based search strategy S2P2P offers a novel path-suggestion based query routing mechanism, providing a reasonable tradeoff between search performance and network traffic overhead. In addition, the first semantic-based data replication scheme DSDR is proposed. It enables peers to use semantic information to select replica numbers and target peers to address predicted future demands. With DSDR, k-random search can achieve better precision and recall than it can with a near-optimal non-semantic replication strategy. Further, this thesis introduces a functional automatic semantic service composition method, SPSC. Distinctively, it enables peers to jointly compose complex workflows with high cumulative recall but low network traffic overhead, using heuristic-based bidirectional haining and service memorization mechanisms. Its query branching method helps to handle dead-ends in a pruned search space. SPSC is proved to be sound and a lower bound of is completeness is given. Finally, this thesis presents iRep3D for semantic-index based 3D scene selection in P2P search. Its efficient retrieval scales to answer hybrid queries involving conceptual, functional and geometric aspects. iRep3D outperforms previous representative efforts in terms of search precision and efficiency.Diese Dissertation bearbeitet Forschungsfragen zur semantischen Suche und Komposition in unstrukturierten Peer-to-Peer Netzen(P2P). Die semantische Suchstrategie S2P2P verwendet eine neuartige Methode zur Anfrageweiterleitung basierend auf Pfadvorschlägen, welche den Stand der Wissenschaft übertrifft. Sie bietet angemessene Balance zwischen Suchleistung und Kommunikationsbelastung im Netzwerk. Außerdem wird das erste semantische System zur Datenreplikation genannt DSDR vorgestellt, welche semantische Informationen berücksichtigt vorhergesagten zukünftigen Bedarf optimal im P2P zu decken. Hierdurch erzielt k-random-Suche bessere Präzision und Ausbeute als mit nahezu optimaler nicht-semantischer Replikation. SPSC, ein automatisches Verfahren zur funktional korrekten Komposition semantischer Dienste, ermöglicht es Peers, gemeinsam komplexe Ablaufpläne zu komponieren. Mechanismen zur heuristischen bidirektionalen Verkettung und Rückstellung von Diensten ermöglichen hohe Ausbeute bei geringer Belastung des Netzes. Eine Methode zur Anfrageverzweigung vermeidet das Feststecken in Sackgassen im beschnittenen Suchraum. Beweise zur Korrektheit und unteren Schranke der Vollständigkeit von SPSC sind gegeben. iRep3D ist ein neuer semantischer Selektionsmechanismus für 3D-Modelle in P2P. iRep3D beantwortet effizient hybride Anfragen unter Berücksichtigung konzeptioneller, funktionaler und geometrischer Aspekte. Der Ansatz übertrifft vorherige Arbeiten bezüglich Präzision und Effizienz
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