Dissertations / Theses: 'Wide area networks (Computer networks) – Evaluation'

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Yang, Yue Carleton University Dissertation Engineering Electrical. "Performance evaluation of an integrated FDDI-ATM-FDDI network." Ottawa, 1992.

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2

Norling, Kristoffer. "A Performance Evaluation of Secure Distributed Co-Simulation over Wide Area Networks." Thesis, Linköping University, Department of Computer and Information Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15786.

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Different types of models often require different tools and environments to be modeled and simulated. These tools and environments are specialized to handle specific purposes. The models created for these special purposes can then be included in the modeling and simulation of large complex systems. This scenario increases the motivation to use a co-simulation technique. Co-simulation allows for coupling of different simulators into one coherent simulation. Different parts of a system are often modeled by different departments within an enterprise or by subcontractors. Since the models often are describing enterprises’ primary know-how they become important business assets. This raises the need for a secure modeling and simulation approach. This thesis discusses different approaches regarding how to securely simulate and distribute models. We focus on a distributed co-simulation approach over wide area networks (WANs), using transmission line modeling (TLM). The approach is tested in an experimental environment at Linköping University, Sweden, and by real condition co-simulations between Sweden and Australia. A series of experiments are conducted using a simulated WAN environment and the results are put in relation to the real encrypted simulations between Sweden and Australia. We measure the performance during the simulations and evaluate the results. We observe that by distributing the co-simulation we suffer from performance losses. These losses and what parameters cause them is our primary emphasis in the evaluation. We also see that there are two types of parameters that affect the total simulation time in the distributed environment. First there are parameters that belong to the models, and then there are parameters that belong to the WAN environment. We conclude that several of the parameters have effect on the total simulation time. Especially the network delay (latency) has a significant impact.

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Lin, Philip J. (Philip Jin-Yi). "Wide area optical backbone networks." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11288.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.
Includes bibliographical references (p. 145-147).
by Philip Jin-Yi Lin.
Ph.D.

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4

Robeson, Bridget M. "A local area network & wide area network design." Master's thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12232009-020117/.

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5

Voelker, Geoffrey Michael. "Cooperative caching in local-area and wide-area networks /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/7010.

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6

Hutchison, Andrew. "Modelling adaptive routing in Wide Area Networks." Master's thesis, University of Cape Town, 1991. http://hdl.handle.net/11427/13555.

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Bibliography: leaves 132-138.
This study investigates the modelling of adative routing algorithms with specific reference to the algorithm of an existing Wide Area Network (WAN). Packets in the network are routed at each node on the basis of routing tables which contain internal and external delays for each route from the node. The internal delay on a route represents the time that packets queued for transmission will have to wait before being transmitted, while the external delay on a route represents the delay to other nodes via that route. Several modelling methods are investigated and compared for the purpose of identifying the most appropriate and applicable technique. A model of routing in the WAN using an analytic technique is described. The hypothesis of this study is that dynamic routing can be modelled as a sequence of models exhibiting fixed routing. The modelling rationale is that a series of analytic models is run and solved. The routing algorithm of the WAN studied is such that, if viewed at any time instant, the network is one with static routing and no buffer overflow. This characteristic, together with a real time modelling requirement, influences the modelling technique which is applied. Each model represents a routing update interval and a multiclass open queueing network is used to solve the model during a particular interval. Descriptions of the design and implementation of X wan, an X Window based modelling system, are provided. A feature of the modelling system is that it provides a Graphical User Interface (GUI), allowing interactive network specification and the direct observation of network routing through the medium of this interface. Various applications of the modelling system are presented, and overall network behaviour is examined. Experimentation with the routing algorithm is conducted, and (tentative) recommendations are made on ways in which network performance could be improved. A different routing algorithm is also implemented, for the purpose of comparison and to demonstrate the ease with which this can be affected.

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Orfanidis, Charalampos. "Robustness in low power wide area networks." Licentiate thesis, Uppsala universitet, Avdelningen för datorteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-351481.

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During the past few years we have witnessed an emergence of Wide Area Networks in the Internet of Things area. There are several new technologies like LoRa, Wi-SUN, Sigfox, that offer long range communication and low power for low-bitrate applications. These new technologies enable new application scenarios, such as smart cities, smart agriculture, and many more. However, when these networks co-exist in the same frequency band, they may cause problems to each other since they are heterogeneous and independent. Therefore it is very likely to have frame collisions between the different networks. In this thesis we first explore how tolerant these networks are to Cross Technology Interference (CTI). CTI can be described as the interference from heterogeneous wireless technologies that share the same frequency band and is able to affect the robustness and reliability of the network. In particular, we select two of them, LoRa and Wi-SUN and carry out a series of experiments with real hardware using several configurations. In this way, we quantify the tolerance of cross technology interference of each network against the other as well as which configuration settings are important. The next thing we explored is how well channel sensing mechanisms can detect the other network technologies and how they can be improved. For exploring these aspects, we used the default Clear Channel Assessment (CCA) mechanism of Wi-SUN against LoRa interference and we evaluated how accurate it is. We also improved this mechanism in order to have higher accuracy detection against LoRa interference. Finally, we propose an architecture for WSNs which will enable flexible reconfiguration of the nodes. The idea is based on Software Defined Network (SDN) principles and could help on our case by reconfiguring a node in order to mitigate the cross-technology interference from other networks.

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8

Dussault, Robert (Joseph Fernand Robert) Carleton University Dissertation Engineering Electrical. "A Diagnostic expert system for wide area networks." Ottawa, 1992.

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9

Knight, Jon. "Supporting distributed computation over wide area gigabit networks." Thesis, Loughborough University, 1995. https://dspace.lboro.ac.uk/2134/7329.

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The advent of high bandwidth fibre optic links that may be used over very large distances has lead to much research and development in the field of wide area gigabit networking. One problem that needs to be addressed is how loosely coupled distributed systems may be built over these links, allowing many computers worldwide to take part in complex calculations in order to solve "Grand Challenge" problems. The research conducted as part of this PhD has looked at the practicality of implementing a communication mechanism proposed by Craig Partridge called Late-binding Remote Procedure Calls (LbRPC). LbRPC is intended to export both code and data over the network to remote machines for evaluation, as opposed to traditional RPC mechanisms that only send parameters to pre-existing remote procedures. The ability to send code as well as data means that LbRPC requests can overcome one of the biggest problems in Wide Area Distributed Computer Systems (WADCS): the fixed latency due to the speed of light. As machines get faster, the fixed multi-millisecond round trip delay equates to ever increasing numbers of CPU cycles. For a WADCS to be efficient, programs should minimise the number of network transits they incur. By allowing the application programmer to export arbitrary code to the remote machine, this may be achieved. This research has looked at the feasibility of supporting secure exportation of arbitrary code and data in heterogeneous, loosely coupled, distributed computing environments. It has investigated techniques for making placement decisions for the code in cases where there are a large number of widely dispersed remote servers that could be used. The latter has resulted in the development of a novel prototype LbRPC using multicast IP for implicit placement and a sequenced, multi-packet saturation multicast transport protocol. These prototypes show that it is possible to export code and data to multiple remote hosts, thereby removing the need to perform complex and error prone explicit process placement decisions.

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Brown, Alan. "Efficient service discovery in wide area networks." Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/489.

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Living in an increasingly networked world, with an abundant number of services available to consumers, the consumer electronics market is enjoying a boom. The average consumer in the developed world may own several networked devices such as games consoles, mobile phones, PDAs, laptops and desktops, wireless picture frames and printers to name but a few. With this growing number of networked devices comes a growing demand for services, defined here as functions requested by a client and provided by a networked node. For example, a client may wish to download and share music or pictures, find and use printer services, or lookup information (e.g. train times, cinema bookings). It is notable that a significant proportion of networked devices are now mobile. Mobile devices introduce a new dynamic to the service discovery problem, such as lower battery and processing power and more expensive bandwidth. Device owners expect to access services not only in their immediate proximity, but further afield (e.g. in their homes and offices). Solving these problems is the focus of this research. This Thesis offers two alternative approaches to service discovery in Wide Area Networks (WANs). Firstly, a unique combination of the Session Initiation Protocol (SIP) and the OSGi middleware technology is presented to provide both mobility and service discovery capability in WANs. Through experimentation, this technique is shown to be successful where the number of operating domains is small, but it does not scale well. To address the issue of scalability, this Thesis proposes the use of Peer-to-Peer (P2P) service overlays as a medium for service discovery in WANs. To confirm that P2P overlays can in fact support service discovery, a technique to utilise the Distributed Hash Table (DHT) functionality of distributed systems is used to store and retrieve service advertisements. Through simulation, this is shown to be both a scalable and a flexible service discovery technique. However, the problems associated with P2P networks with respect to efficiency are well documented. In a novel approach to reduce messaging costs in P2P networks, multi-destination multicast is used. Two well known P2P overlays are extended using the Explicit Multi-Unicast (XCAST) protocol. The resulting analysis of this extension provides a strong argument for multiple P2P maintenance algorithms co-existing in a single P2P overlay to provide adaptable performance. A novel multi-tier P2P overlay system is presented, which is tailored for service rich mobile devices and which provides an efficient platform for service discovery.

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Valancius, Vytautas. "Wide-area route control for online services." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43623.

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Accelerated by on-demand computing, the number and diversity of the Internet services is increasing. Such online services often have unique requirements for the underlying wide-area network: For instance, online gaming service might benefit from low delay and jitter paths to client, while online data backup service might benefit from cheaper paths. Unfortunately, today's Internet does not accommodate fine-grained, service-specific wide-area route control. In this dissertation, I achieve the following goals: 1) improve the access to the routes, 2) quantify the benefits of fine-grained route control, and 3) evaluate the efficiency of current payment schemes for the wide-area routes. * Improving access to wide-area route control. Online services face significant technological and procedural hurdles in accessing the routes: Each service in need to control the Internet routes, has to obtain own equipment, Internet numbered resources, and establish contracts with upstream ISPs. In this dissertation, I propose and describe implementation and deployment of a secure and scalable system which provides on-demand access to the Internet routes. In setting such as cloud data center, the system can support multiple online services, providing each service with an illusion of direct connectivity to the neighboring Internet networks, which, for all practical purposes, allows services to participate fully in the Internet routing. * Quantifying the benefits of fine-grained route control. Even if online services are presented with wide-area route choice, it is not clear how much tangible benefit such choice provides. Most modern Online Service Providers (OSP) rely primarily on the content routing to improve network performance between the clients and the replicas. In this dissertation, I quantify the potential benefit the OSPs can gain if they perform a joint network and content routing. Among other findings, I find that by performing joint content and network routing, OSPs can achieve 22% larger latency reduction than can be obtained by content routing alone. * Modeling and evaluating the efficiency of the current payment schemes for wide-area routes. Finally, increasing diversity and sophistication of the online services participating in the Internet routing poses a challenge to payment models used in today's Internet. Service providers today charge business customers a blended rate: a single, "average" price for unit of bandwidth, without regard to cost or value of individual customer's flows. In my dissertation, I set to understand how efficient this payment model is and if more granular payment model, accounting for the cost and value of different flows could increase the ISP profit and the consumer surplus. I develop an econometric demand and cost model and map three real-world ISP data sets to it. I find that ISPs can indeed improve the economic efficiency with just a few pricing tiers.

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12

Siebler, Matthias David. "Efficient topology update on high speed wide area networks." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36579.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.
Includes bibliographical references (leaves 42-43).
by Mathias David Siebler.
M.Eng.

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13

Zhang, Jianjun. "Efficient Information Dissemination in Wide Area Heterogeneous Overlay Networks." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/16129.

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In this dissertation research we study and address the unique challenges involved in information sharing and dissemination of large-scale group communication applications. We focus on system architectures and various techniques for efficient and scalable information dissemination in distributed P2P environments. Our solutions are developed by targeting at utilizing three representative P2P overlay networks: structured P2P network based on consistent hashing techniques, unstructured Gnutella-like P2P network, and P2P GeoGrid based on geographical location and proximity of end nodes. We have made three unique contributions to the general field of large-scale information sharing and dissemination. First, we propose a landmark-based peer clustering techniques to grouping end-system nodes by their network proximity, and a communication management technique addresses load balancing and reliability of group communication applications in structured P2P network. Second, we develop a utility-based P2P group communication service middleware, consisting of a utility-based topology management and a utility-aware P2P routing, for providing scalable and efficient group communication services in an unstructured P2P overlay network of heterogeneous peers. Third, we propose an overlay network management protocol that is aware of the geographical location of end-system nodes and a set of routing and adaptation techniques, aiming at building decentralized information dissemination service networks to support location-based applications and services. Although different overlay networks require different system designs for building scalable and efficient information dissemination services, we have employed two common design philosophies: (1) exploiting end-system heterogeneity and (2) utilizing proximity information of end-system nodes to localize most of the communication traffic, and (3) using randomized shortcuts to accelerate long-distant communications. We have demonstrated our design philosophies and the performance improvements in the above three types of P2P overlay networks. Concretely, by assigning more workloads to more powerful peers, we can greatly increase the system scalability and reduce the variation of workload distribution. By clustering end-system nodes based on their IP-network proximity or their geographical proximity, and utilizing randomized shortcuts, we can reduce the end-to-end communication latency, balance peer workloads against service request hotspots across the overlay network, and significantly enhance the scalability and efficiency of large-scale decentralized information dissemination and group communication.

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14

Topol, Brad Byer. "A framework for the development of wide area distributed applications." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/8300.

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15

Xu, Zheming, and 徐哲明. "WAVNet: wide-area virtual networks for dynamic provisioning of IaaS." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4575956X.

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16

Qureshi, Asfandyar. "Flexible application driven network striping over Wireless Wide Area Networks." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33338.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.
Includes bibliographical references (p. 157-161).
Inverse multiplexing, or network striping, allows the construction of a high-bandwidth virtual channel from a collection of multiple low-bandwidth network channels. Striping systems usually employ a packet scheduling policy that allows applications to be oblivious of the way in which packets are routed to specific network channels. Though this is appropriate for many applications, many other applications can benefit from an approach that explicitly involves the application in the determination of the striping policy. Horde is middleware that facilitates flexible striping over Wireless Wide Area Network (WWAN) channels. Horde is unusual in that it separates the striping policy from the striping mechanism. It allows applications to describe network Quality-of-Service (QoS) objectives that the striping mechanism attempts to satisfy. Horde can be used by a set of data streams, each with its own QoS policy, to stripe data over a set of WWAN channels. The WWAN QoS variations observed across different channels and in time, provide opportunities to modulate stream QoS through scheduling. The key technical challenge in Horde is giving applications control over certain aspects of the data striping operation while at the same time shielding the application from low-level details. Horde exports a set of flexible abstractions replacing the application's network stack. Horde allows applications to express their policy goals as succinct network-QoS objectives. Each objective says something, relatively simple, about the sort of network QoS an application would like for some data stream(s). We present the Horde architecture, describe an early implementation, and examine how different policies can be used to modulate the quality-of-service observed across different independent data streams. Through experiments conducted on real and simulated network channels, we confirm our belief that the kind of QoS modulation Horde aims to achieve is realistic for actual applications.
by Asfandyar Qureshi.
M.Eng.

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17

Hill, Kevin Carlos. "Design of a local area network and a wide area network to connect the US Navy's training organization." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10242009-020032/.

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18

Tewari, Renu. "Architectures and algorithms for scalable wide-area information systems /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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19

Brakmo, Lawrence Sivert. "End-to-end congestion detection and avoidance in wide area networks." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282192.

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As human dependence on wide area networks like the Internet increases, so does contention for the network's resources. This contention has noticeably affected the performance of these networks, reducing their usability. This dissertation addresses this problem in two ways. First, it describes TCP Vegas, a new implementation of TCP that is distinguished from current TCP implementations by containing a new congestion detection and avoidance mechanism. This mechanism was designed to work in currently available wide area networks and achieves between 37% and 71% better throughput on the Internet, with one-fifth to one-half the losses, as compared to the current implementation of TCP. Second, it describes x-Sim, a network simulator based on the x-kernel, that is able to simulate the topologies and traffic patterns of large scale networks. The usefulness of the simulator to analyze and debug network components is illustrated throughout this dissertation.

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Lin, Katherine Xiaoyan. "Green optical network design : power optimization of wide area and metropolitan area networks." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66434.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 133-134).
Advancements in technology are fueling huge growth in network traffic capacity. Demand for low cost, reliable, and high bitrate transmissions grows 40-110% internationally every year. To date, most research has focused on cost minimization of wide area and metropolitan area networks. In this thesis, we concentrate instead on finding scalable WAN designs with respect to power constraints and optimal MAN topologies with minimal capital and operating expenditures. We find optical bypass networks to be most scalable with respect to power consumption, especially when quality of service and network flexibility, reliability, and protection are considered. The power consumption of the standard bypass network can be lowered further through a hybrid design in which whole wavelengths of core, stable traffic between node pairs are routed via direct, fixed lightpaths using patch panelling and unexpected, bursty traffic is switched on a standard optical bypass network. We analyze power distribution among components and find the OXC switch most scalable at each node and O/E/O switches and routers wasteful. Finally, we prove that shortest path and minimum hop routing is power optimal and traffic balanced routing should be avoided. We approximate MAN topologies with regular graphs for tractable analysis. We augment a previous cost-based joint optimization formulation [13] with power expenditure modelling and obtain closed form solutions for optimal node degree and normalized network costs. We find that the optimal node connectivity increases 20-25% due to the added operating expenditures. Normalized network cost and normalized network cost per unit traffic also rise by approximately 25%. Our results show that the Generalized Moore graph with node degree between 0.05N and 0.08N is both power and cost minimal for a purely optical network.
by Katherine Xiaoyan Lin.
M.Eng.

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21

Malik, Omair S. (Omair Safwan). "Quality of service analysis for audio over cellular voice networks and cellular wireless wide area networks." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/45975.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.
Includes bibliographical references (p. 51-[55]).
Cellular Wireless Wide Area Networks (WWANs) are most prevalent and offer high-bandwidth data transfer. We believe WWANs can be availed for voice communications employing Voice Over IP technologies. Such a communication will be of better quality and offer higher resilience compared to voice communication over a cellular phone (using cellular voice networks). We present a Quality of Service analysis of one-way voice communication over cellular voice networks and cellular WWANs. By studying different quality metrics we test if WWANs offer a better solution for voice communications compared to traditional cellular voice networks. We also study if employing more than one WWANs or cellular voice networks leads to a higher resilience in voice communication.
by Omair S. Malik.
M.Eng.

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22

McGovern, Susan C. "Information security requirements for a coalition wide area network." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA397542.

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Thesis (M.S. in Systems Technology (Command, Control, and Communications)) Naval Postgraduate School, June 2001.
Thesis advisor(s): Irvine, Cynthia E. "June 2001." Includes bibliographical references (p. 77-78). Also available online.

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Bogle, Jeremy(Jeremy P. ). "A fundamental approach for providing service-level guarantees for wide-area networks." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122998.

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This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 55-58).
To keep up with the continuous growth in demand, cloud providers spend millions of dollars augmenting the capacity of their wide-area backbones and devote significant effort to efficiently utilizing WAN capacity. A key challenge is striking a good balance between network utilization and availability, as these are inherently at odds; a highly utilized network might not be able to withstand unexpected traffic shifts resulting from link/node failures. I motivate this problem using real data from a large service provider and propose a solution called TeaVaR (Traffic Engineering Applying Value at Risk), which draws on financial risk theory to realize a risk management approach to traffic engineering (TE). I leverage empirical data to generate a probabilistic model of network failures, and formulate a Linear Program (LP) that maximizes bandwidth allocation to network users subject to a service level agreement (SLA). I prove TeaVaR's correctness, and then compare it to state-of-the-art TE solutions with extensive simulations across many network topologies, failure scenarios, and real-world traffic patterns. The results show that with TeaVaR, operators can support up to twice as much throughput as other TE schemes, at the same level of availability. I also construct a simulation tool that builds on my implementation of TeaVaR and simulates its usage in the data plane. This tool can be useful not only for testing TE schemes but also for capacity planning, as it allows network operators to see how their network is performing, where the bottlenecks are, and what kind of demand loads it can handle.
by Jeremy Bogle.
M. Eng.
M.Eng. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science

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Zhang, Weida, and 张伟达. "Adaptive live VM migration over WAN: modelingand implementation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50534270.

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The combination of traditional process migration and the new virtualization technology enables mobility of virtual machines and resource provisioning within data centers. While applied to wide area network (WAN), a traditional migration algorithm has to adjust itself according to the various WAN situations and VM status. This thesis identifies four performance measurements of a VM migration: total migration time, downtime, remote up time and performance degradation. It observes that the total migration time and the remote up time of traditional pre-copy over WAN is too long to tolerate. This thesis claims that even for WAN, post-copy could be used to improve the total migration time and remote up time, only by introducing tolerable, predictable and controllable performance degradation. The adaptiveness of the migration algorithm is concerned. It proposes a hybrid solution of pre-copy and post-copy, both for memory and storage, to do the migration. In the hybrid solution, a fraction of memory (Mfrac) and a fraction of storage (Sfrac) are migrated in the pre-copy and freeze-and-copy phase, and the remaining are migrated in the post-copy phase. A model-based solution with the help of profiling is proposed to adaptively find the best combination of Mfrac and Sfrac. The evaluation part suggests that the proposed solution could adapt to different application behaviors and network conditions.
published_or_final_version
Computer Science
Master
Master of Philosophy

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25

Najarian, Aida. "The Arab world on-line : Arab-American communities using the Internet." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/16938.

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Khazan, Roger Igor. "A one-round algorithm for virtually synchronous group communication in wide area networks." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/29235.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (p. 159-165).
Group communication services, and especially those that implement Virtual Synchrony semantics, are powerful middleware systems that facilitate the development of fault-tolerant distributed applications. In this thesis, we present a high quality, theoretical design of a group communication service that implements Virtual Synchrony semantics and is aimed for deployment in wide-area networks (WANs). The design features a novel algorithm for implementing Virtual Synchrony semantics; the algorithm is more appropriate for WANs than the existing solutions because it involves fewer rounds of communication and operates in a scalable WAN-oriented architecture. The high quality of the design refers to the level of formality and rigor at which it is done: The design includes formal and precise specifications, algorithms, correctness proofs, and performance analyses. We develop the necessary supporting theory and methodology required for producing and evaluating this design. In particular, we develop a formal, inheritance-based, methodology that supports incremental construction of specifications, models, and proofs. This methodology helps us manage the complexity of the design and makes it evident which part of the algorithm implements which property of the system. We also develop new, formal approaches in the area of performance evaluation.
by Roger I. Khazan.
Ph.D.

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27

Brande, Julia K. Jr. "Computer Network Routing with a Fuzzy Neural Network." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29685.

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The growing usage of computer networks is requiring improvements in network technologies and management techniques so users will receive high quality service. As more individuals transmit data through a computer network, the quality of service received by the users begins to degrade. A major aspect of computer networks that is vital to quality of service is data routing. A more effective method for routing data through a computer network can assist with the new problems being encountered with today's growing networks. Effective routing algorithms use various techniques to determine the most appropriate route for transmitting data. Determining the best route through a wide area network (WAN), requires the routing algorithm to obtain information concerning all of the nodes, links, and devices present on the network. The most relevant routing information involves various measures that are often obtained in an imprecise or inaccurate manner, thus suggesting that fuzzy reasoning is a natural method to employ in an improved routing scheme. The neural network is deemed as a suitable accompaniment because it maintains the ability to learn in dynamic situations. Once the neural network is initially designed, any alterations in the computer routing environment can easily be learned by this adaptive artificial intelligence method. The capability to learn and adapt is essential in today's rapidly growing and changing computer networks. These techniques, fuzzy reasoning and neural networks, when combined together provide a very effective routing algorithm for computer networks. Computer simulation is employed to prove the new fuzzy routing algorithm outperforms the Shortest Path First (SPF) algorithm in most computer network situations. The benefits increase as the computer network migrates from a stable network to a more variable one. The advantages of applying this fuzzy routing algorithm are apparent when considering the dynamic nature of modern computer networks.
Ph. D.

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28

Iqneibi, Sami M. Carleton University Dissertation Engineering Electrical. "A blackboard architecture to support network fault diagnosis." Ottawa, 1992.

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29

Buyya, Rajkumar 1970. "Economic-based distributed resource management and scheduling for grid computing." Monash University, School of Computer Science and Software Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/8760.

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Fang, Jun-Wai 1960. "Design and performance evaluation of a proposed backbone network for PC-Networks interconnection." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276941.

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This thesis is concerned with the design of a high-speed backbone network which provides a high bandwidth interconnection for various Personal Computer Networks (PC-Networks) with an integrated service of voice and data. With the advanced technology of optical fiber as the transmission medium, several different existing topologies and protocols are discussed for the backbone network design. The token ring protocol is simulated and evaluated to find out a suitable buffer size and the length of voice and data packet for backbone network. The Network II.5 simulation tool is applied to simulate the token ring simulation model with different parameters. The Network Interface Unit (NIU) is designed from the simulation results with a cost-effective consideration.

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Robinson, Ricky. "A resource discovery protocol for modern computing environments /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19055.pdf.

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Viens, Francois (Joseph Lucien Francois) Carleton University Dissertation Engineering Electrical. "A neural network approach to detect traffic anomalies in a communication network." Ottawa, 1992.

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Rabinovich, Michael. "Efficient replication management in distributed systems /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/6905.

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Montehermoso, Ronald Centeno. "Microsoft Windows Server 2003 : security enhancements and new features /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FMontehermoso.pdf.

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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, Sept. 2004.
Thesis Advisor(s): Douglas E. Brinkley. Includes bibliographical references (p. 111-118). Also available online.

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35

Lee, Jackson Ying-Kin. "Performance evaluation of the integration of voice and data in a high-speed local area computer network : the Expressnet." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26902.

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A high-speed local area communication network--the Expressnet--is investigated in this thesis with regard to voice and data transmissions. Performance criteria, such as channel utilizations, delay characteristics, and queue lengths are determined from computer simulation and numerical calculation approaches. The protocol is particularly suitable for the transmission of packetized voice as it is able to guarantee an upper bound on the transmission delay for each packet. The network under study thus will find major application in future office automation, where large amounts of voice will be integrated with data.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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Johansson, David. "An Evaluation of Shortest Path Algorithms on Real Metropolitan Area Networks." Thesis, Linköping University, Department of Computer and Information Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17491.

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This thesis examines some of the best known algorithms for solving the shortest point-to-point path problem, and evaluates their performance on real metropolitan area networks. The focus has mainly been on Dijkstra‟s algorithm and different variations of it, and the algorithms have been implemented in C# for the practical tests. The size of the networks used in this study varied between 358 and 2464 nodes, and both running time and representative operation counts were measured.

The results show that many different factors besides the network size affect the running time of an algorithm, such as arc-to-node ratio, path length and network structure. The queue implementation of Dijkstra‟s algorithm showed the worst performance and suffered heavily when the problem size increased. Two techniques for increasing the performance were examined: optimizing the management of labelled nodes and reducing the search space. A bidirectional Dijkstra‟s algorithm using a binary heap to store temporarily labelled nodes combines both of these techniques, and it was the algorithm that performed best of all the tested algorithms in the practical tests.

This project was initiated by Netadmin Systems i Sverige AB who needed a new path finding module for their network management system NETadmin. While this study is primarily of interest for researchers dealing with path finding problems in computer networks, it may also be useful in evaluations of path finding algorithms for road networks since the two networks share some common characteristics.

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Lu, Jie. "Performance evaluation of packet video transfer over local area networks." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06162009-063207/.

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Cole, Carl F. "Application of the systems engineering process to develop a wide area network communications system upgrade design." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-03302010-020445/.

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39

Tam, Fung-har Wallis. "Analysis of internet industry in Hong Kong : using Hong Kong Telecom as the case study /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18024749.

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40

Muangmode, Korawan. "The reaction evaluation of Blue Drive online tutorial at University of Wisconsin-Stout." Online version, 2008. http://www.uwstout.edu/lib/thesis/2008/2008muangmodek.pdf.

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Hon, Lenny Kwok-Ming. "Performance evaluation of the movable-slot TDM protocol and its application in metropolitan area networks." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26706.

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Movable-slot time-division multiplexing (MSTDM) is a medium access control protocol for the integration of voice and data in local area networks. In this thesis, the performance of this protocol is evaluated through mathematical analysis and simulation. Its application in metropolitan area networks is also studied. For the performance evaluation, a non-pre-emptive priority queuing model is first proposed for analysing the mean data delay characteristic of the slotted non-persistent carrier-sense multiple access with collision detection (CSMA/CD) protocol. Then this analytical approach is extended to the slotted MSTDM protocol with non-persistent data packet transmission, and its mean data delay performance is obtained. Numerical results from the analysis are shown and discussed. Moreover, simulation study of the MSTDM protocol is performed. Through the simulation results, the effects of this protocol on the general delay performances of voice and data are discussed. It is found that if first voice packets, which are generated at the beginning of talkspurts, are given a shorter retransmission delay than data packets, the channel-acquisition delay for voice sources can be reduced without sacrificing the data delay performance significantly. The simulation results are also used to verify the analytical results. As the comparisons show, the accuracy of the analysis is high although it is based on a simple approximate model. For the application of MSTDM in metropolitan area networks, a scheme which alleviates the distance and transmission rate constraints associated with this protocol is described. The approach is to divide the stations in a large area into regional groups, each operating in a different frequency band. Each group forms a sub-network which is part of the metropolitan area network. An access protocol is proposed for interconnecting these sub-networks. Also an analysis which finds the optimum number of sub-networks for interconnection is presented. The criterion is to minimize the mean data delay for communications in a sub-network.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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42

Mishra, Amitabh. "Modeling and Performance Evaluation of Wireless Body Area Networks for Healthcare Applications." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439281330.

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43

Saini, J. S. "The design and evaluation of digital macro systems with particular reference to local area networks." Thesis, University of Southampton, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356530.

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Pham, Don H. "Medium access delay evaluation for distributed queueing [sic] dual bus (DQDB) MAC protocol /." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/44732.

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Distributed Queuing Dual Bus (DQDB) is a media access control (MAC) technique, which is being considered by the IEEE 802.6 for the metropolitan area network (MAN). The DQDB medium access technique has many promising advantages over other access methods. However it has one drawback, which is its unfairness in terms of node-dependent medium access delay. In this paper a mathematic model is formulated to describe this detrimental behavior of DQDB. The access control method is first modeled as a M/G/1 queueing system with a single priority level, then it is remodeled as a non-preemptive priority system with three priority levels. By employing these models, the approximate medium access delay analysis of a DQDB network is investigated for a metropolitan area network containing 50 stations with a channel bandwidth of 150 Mbps. Numerical results are then presented to illustrate the network unfairness performance under various traffic intensities and under different priority levels. The results have been obtained for non-isochronous (asynchronous) traffic.
Master of Science

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45

Kelly, Paul Vincent. "Living in the digital divide the lived experience of students without access to computers & the internet /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/5895.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 13, 2007) Vita. Includes bibliographical references.

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Lenaburg, Allen Gregg. "Intranet concept for small business." CSUSB ScholarWorks, 2004. https://scholarworks.lib.csusb.edu/etd-project/2710.

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The purpose of this project is to build a working intranet containing core applications that create the framework for a small business intranet. Small businesses may benefit from an intranet because of its ability to effectively streamline the processes for retrieving and distributing information. Intranets are internal networks using TCP/IP protocols, Web server software, and browser client software to share information created in HTML within an organization, and to access company databases.

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CORDEIRO, CARLOS DE MORAIS. "MEDIUM ACCESS CONTROL PROTOCOLS AND ROUTING STRATEGIES FOR WIRELESS LOCAL AND PERSONAL AREA NETWORKS." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1070579302.

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James, Ingrimar. "A cisco-based proposal for ARNe core routing infrastructure." [Denver, Colo.] : Regis University, 2009. http://adr.coalliance.org/codr/fez/view/codr:145.

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Mascarenhas, da Veiga Alves Manoel Eduardo. "Characterisation of end-to-end performance for web-based file server respositories." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09ENS/09ensm395.pdf.

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Bibliography: leaves 128-135. Investigates the behaviour of TCP bulk file transfer application sessions in a broadband access environment. Introduces some concepts for evaluating network behaviour: a path instability parameter for analyzing different TCP connections; a minimum RTT delay and a minimum typical path for estimating path characteristics between a client and application servers.

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Kwok, Ki-wa Joyce. "Hong Kong international telecommunications : strategic issues /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1883727X.

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Dissertations / Theses on the topic 'Wide area networks (Computer networks) – Evaluation'

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