Digital Communications and Networking Commons^™

Multicast Algorithms For Mobile Satellite Communication Networks, Ryan W. Thomas

Theses and Dissertations

With the rise of mobile computing and an increasing need for ubiquitous high speed data connections, Internet-in-the-sky solutions are becoming increasingly viable. To reduce the network overhead of one-to-many transmissions, the multicast protocol has been devised. The implementation of multicast in these Low Earth Orbit (LEO) constellations is a critical component to achieving an omnipresent network environment. This research examines the system performance associated with two terrestrial-based multicast mobility solutions, Distance Vector Multicast Routing Protocol (DVMRP) with mobile IP and On Demand Multicast Routing Protocol (ODMRP). These protocols are implemented and simulated in a six plane, 66 satellite LEO constellation. …

Hopfield Model For Shortest Path Computation And Routing In Atm Network, Chee Weng Lee

Student Works (2000-2009)

This research focuses on the application of Hopfield neural network and Boltmann machine in solving the shortest path routing problem in the ATM network environment. Hopfield neural network and Boltzmann machine are two types of neural network which are commonly used for solving optimization problem such as the shortest path routing problem. The objectives of this research are to construct a Hopfield neural network and a Boltzmann machine for solving the shortest path routing problem in the ATM network. Both of these two types of neural network are built based on a chosen example of an A TM network. The …

Aplikasi Wayarles Menggunakan Telefon Bimbit Dengan-Wap, Wan Osman Wan Maria

Student Works (2000-2009)

“Wireless Site Solution using WAP-enabled Mobile Phone” is an application developed based on WAP technology. It makes use of the N-tier Client/Server Architecture to provide users especially those who are still new in this technology. With wireless access to manage their daily task and get latest information as well. The main purpose of this project is to provide an alternative for users in managing their daily tasks in some simple clicks and also to allow users to access information in a very interesting way. There are two major modules in this application which are the user module and administrator module. …

Atm Lane Simulator, Kim Joo Ching

Student Works (2000-2009)

This project describes the development of ATM Local Area Network Emulation (LANE) simulator components. In LANE, an A TM network is configured to simulate an Ethernet or token ring network and coexist with the legacy network without making any modification to Them.The development of this simulator incorporates several important features. The most important feature of the simulator is that it is build based on object-oriented approach, which is able to provide the benefits of re usability, flexibility and extensibility. The second important feature is that it supports multi threaded operations. This means that every object able to act simultaneously. Besides …

Messaging Application, Hooi Phaik Yew

Student Works (2000-2009)

Statistics have shown that more and more people are switching to WAP (Wireless Application Protocol) handphones and most people would have heard of WAP before. Undeniably WAP's future is bright and WAP applications prospects are even better. This alone has encouragrd many programmers into developing WAP applications. Study had shown that this is true in part of the world with more and more hooking up to WAP hand phones. Internet Messaging programs have existed for a long time. Currently there's no WAP Messaging Application (WAP-MA) but it's just a matter of time before somebody invented it. This project is involved …

Sistem Penganalisa Rangkaian (Nas), Mohd Haris Afiatul Syahrizat

Student Works (2000-2009)

Sistem Penganalisa Rangkaian (Nas) merupakan tajuk untuk latihan ilmiah saya bagi memenuhi keperluan Ijazah Sarjana Muda Sains Komputer. Projek ini di bawah penyeliaan Cik Fazidah Othman merupakan sebuah sistem pemantauan aktiviti rangkaian (LAN) “standalone” dan interaktif. Sistem ini dibangunkan berlandaskan kehendak penggunanya yang lebih ditumpukan kepada pentadbir dan jurutera rangkaian sendiri. Sistem ini dapat membantui pentadbir rangkaian dalam memantau aktiviti semasa rangkaian. Ini membolehkan pentadbir rangkaian mendapatkan statistik aktiviti-aktiviti rangkaian yang berjalan yang merangkumi aktiviti internet dan keluar masuk data di dalam rangkaian. Sistem ini dibangunkan menggunakan perisian Microsoft Visual Basic 6.0, Microsoft Access 2000 dan boleh dilarikan pada persekitaran …

Bluetooth Software On Linux, Wireless Hand-Held Devices, Teck Khoon Low

Theses : Honours

In order to enable existing computers (non-Bluetooth ready) to connect to a Bluetooth piconet, a Bluetooth hardware device comprising of the Radio antenna, the baseband and control circuit is used. The digital portion of this device is also known as a Host Controller, HC. In the traditional communication lingo, the Bluetooth Hardware functions, as the Data Communication Equipment (DCE) while the Host is the Data terminal Equipment (DTE). This report discusses the theory and implementation of the communication protocol between the Host and the Host Controller, enabling communication between the computer and the Bluetooth hardware

Design And Implementation Of An Intranet-Solution Especially With Workflow Aspects, Robert Loew

Theses

An Intranet support a new or simply an easier information system for all the workers within a company using internet technology. On the one hand, employees can use Web technology and very simple tools to provide and navigate information. On the other hand, the costly and time-consuming business of installing and maintaining software on local PCs can be avoided by using Browser-based Intranet applications. Ideally, it would be possible to access all forms of information processing using one and the same Web browser. This is the aim of the Intranet Project upon which this thesis is based.

Various technologies for …

Online Whiteboard (Audio Conferencing Module), Chan Weng Wong

Student Works (2000-2009)

Computer technology is a very dynamic and changing field. There are always new technologies being developed and adopted on all fronts, which makes it an exciting field to be in. So, in order to catch up with the technology, I choose myself to investigate some of the telecommunication technology specifically voice networking on the computer. Through this project, I hope I can learn everything regarding to voice networking and thus can build a complete voice communication package for the whiteboard system project as an enhancement to the system. In order to accomplish this project, me together with two of my …

Development Of Object-Oriented Components For Atm Network Simulation With Emphasis On Congestion Control, Wai Kit Sin

Student Works (2000-2009)

Asynchronous Transfer Mode (ATM) is a very high-speed transmission technology. The barrage of technological advancements has continuously enhanced the network performance. There is an increasing dependence on the network. Thus, there is a need to accurately predict the impact of network and applications changes in the dynamic network environment. The network simulator is a tool to analyze the behavior of ATM networks without the expense of building a real network. The simulation of this simulator will give the results that imitate the real network environment. The aim of this project is to develop object-oriented components for an ATM Network Simulator …

Design And Develop A Generic Cut-Through Switch, Nazaruddin Noraini

Student Works (2000-2009)

Today's advancement in network is related to the advancement of packet switching technology. Switching directs network traffic in an efficient manner – it sends information directly from the port of origin to only its destination port. Without switching, many networks are experiencing bandwidth shortages because of an increase in traffic due to the increased numbers of users, the amount of data transported between client/server applications, and the inefficient traffic patterns of some networks. Transmission of data from one destination to another is unguaranty successful. Sometimes the data will lost or conupted during transmission to destination port. To make data more …

Network Simulation And Performance Evalution Of Ip Multicast Using Pim-Dm In Umjanetsim, Jui Hiangh Teoh

Student Works (2000-2009)

The demand for multicast capabilities in IP networks is growing very rapidly. New applications that take advantage of IP Multicast are being introduced constantly. Therefore, IP Multicast is regarded as one of the most important technologies in IP networks today. This dissertation focuses on the simulation and performance evaluation of IP Multicast using Protocol Independent Multicast- Dense Mode (PIM-OM) as the multicast routing protocol. The simulation is executed in a network simulator named UMJaNetSim, where custom components are built in order to simulate IP Multicast. First, the advantages and applications of IP Multicast, multicast addressing, Internet Group Management Protocol (IGMP), …

Mpls Vpn Simulation Using Mp-Ibgp, Tan Fong Ang

Student Works (2000-2009)

As Internet traffic continues to increase, companies are demanding greater speeds and better services to disseminate information to their customers, partners and employees. In order to provide reliable services and to support a variety of secure communications among a wide range of locations, Multiprotocol Label Switching Virtual Private Network (MPLS VPN) has been introduced. MPLS is an emerging technology that aims to address many of the existing issues associated with packet forwarding in today's internetworking environment. Whereas, VPN provides secure private connections through public infrastructure amongst multiple locations. MPLS­ based VPN provides isolation. security, simplified routing, easier provisioning as well …

Arc - An Oai Service Provider For Digital Library Federation, Xiaoming Liu, Kurt Maly, Mohammad Zubair, Michael L. Nelson

Computer Science Faculty Publications

The usefulness of the many on-line journals and scientific digital libraries that exist today is limited by the inability to federate these resources through a unified interface. The Open Archive Initiative (OAI) is one major effort to address technical interoperability among distributed archives. The objective of OAI is to develop a framework to facilitate the discovery of content in distributed archives. In this paper, we describe our experience and lessons learned in building Arc, the first federated searching service based on the OAI protocol. Arc harvests metadata from several OAI compliant archives, normalizes them, and stores them in a search …

Smart Objects And Open Archives, Michael L. Nelson, Kurt Maly

Computer Science Faculty Publications

Within the context of digital libraries (DLs), we are making information objects "first-class citizens". We decouple information objects from the systems used for their storage and retrieval, allowing the technology for both DLs and information content to progress independently. We believe dismantling the stovepipe of "DL-archive-content" is the first step in building richer DL experiences for users and insuring the long-term survivability of digital information. To demonstrate this partitioning between DLs, archives and information content, we introduce "buckets": aggregative, intelligent, object-oriented constructs for publishing in digital libraries. Buckets exist within the "Smart Object, Dumb Archive" (SODA) DL model, which promotes …

Buckets: Smart Objects For Digital Libraries, Michael L. Nelson

Computer Science Faculty Publications

Current discussion of digital libraries (DLs) is often dominated by the merits of the respective storage, search and retrieval functionality of archives, repositories, search engines, search interfaces and database systems. While these technologies are necessary for information management, the information content is more important than the systems used for its storage and retrieval. Digital information should have the same long-term survivability prospects as traditional hardcopy information and should be protected to the extent possible from evolving search engine technologies and vendor vagaries in database management systems. Information content and information retrieval systems should progress on independent paths and make limited …

3d Outside Cell Interference Factor For An Air-Ground Cdma ‘Cellular’ System, David W. Matolak

Faculty Publications

We compute the outside-cell interference factor of a code-division multiple-access (CDMA) system for a three-dimensional (3-D) air-to-ground (AG) "cellular-like" network consisting of a set of uniformly distributed ground base stations and airborne mobile users. The CDMA capacity is roughly inversely proportional to the outside-cell interference factor. It is shown that for the nearly free-space propagation environment of these systems, the outside-cell interference factor can be larger than that for terrestrial propagation models (as expected) and depends approximately logarithmically upon both the cell height and cell radius.

Crop Updates 2000 Cereals - Part 3, Roslyn J. Jettner, Blakely Paynter, Glenn Macdonald, Pierre Fievez, Ian Foster, David Tennant, Wal Anderson, James Ridsdill-Smith, Celia Pavri, Ross Chapman, Senthold Asseng, Steve Carr, Brad Nutt, Lindrea Latham, Roger Jones, Anyou Liu, Clinton K. Revell, David Ferris, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Ted Woodburn, Paul Yeoh, Ian Rose, Anita Lyons, Simon Cook, Matthew L. Adams, Robert J. Corner

Crop Updates

This session covers eighteen papers from different authors:

BARLEY AND OAT AGRONOMY

1. Unicorn barley must meet malting specifications to be a viable option, Roslyn Jettnerand Blakely Paynter, Agriculture Western Australia

2. Optimum oat seed rates, Glenn McDonald, Agriculture Western Australia

3. Production and Quality of export Oaten Hay (1998 and 1989), Pierre Fievez, Pierre Fievez and Associates

FROST

4. Climatology of Frost in Southern Western Australia, Ian Foster, Agriculture Western Australia

5. Flowering calculator, David Tennant, Agriculture Western Australia

6. Some options for managing the risk of frost damage, Wal Anderson, Agriculture Western Australia

PASTURE

7. …

Security In Distributed Systems - A Framework For Different Application Types, Ingo Stengel

Theses

Security is a factor which decides upon the applicability of distributed applications. Therefore this thesis deals with security in distributed systems. The complexity of the existing distributed technologies makes it necessary to reduce the number of distributed technologies considered in this thesis, i.e. concentrating on: Java, Mobile Agents and CORBA, where only Java-based mobile agents will be considered.

After a short review of basic security principles including firewalls, existing security problems in the above mentioned distributed technologies are analysed. Additional generic problems in distributed systems are outlined.

Solutions are referring to two different areas: those regarding security problems with firewalls …

The Ups Prototype: An Experimental End-User Service Across E-Print Archives, Herbert Van De Sompel, Thomas Krichel, Michael L. Nelson, Patrick Hochstenbach, Victor Lyapunov, Kurt Maly, Mohammad Zubair, Mohamed Kholief, Xiaoming Liu, Heath O'Connell

Computer Science Faculty Publications

A meeting was held in Santa Fe, New Mexico, October 21-22, 1999, to generate discussion and consensus about interoperability of publicly available scholarly information archives. The invitees represented several well known e-print and report archive initiatives, as well as organizations with interests in digital libraries and the transformation of scholarly communication. The central goal of the meeting was to agree on recommendations that would make the creation of end-user services -- such as scientific search engines and linking systems -- for data originating from distributed and dissimilar archives easier. The Universal Preprint Service (UPS) Prototype was developed in preparation for …

Multicast Services For Multimedia Collaborative Applications, Emad Eldin Mohamed Mohamed

Computer Science Theses & Dissertations

This work aims at providing multicast services for multimedia collaborative applications over large inter-networks such as the Internet. Multimedia collaborative applications are typically of small group size, slow group membership dynamics, and awareness of participants' identities and locations. Moreover, they usually consist of several components such as audio, video, shared whiteboard, and single user application sharing engines that collectively help make the collaboration session successful. Each of these components has its demands from the communication layer that may differ from one component to another. This dissertation identifies the overall characteristics of multimedia collaborative applications and their individual components. It also …

Network Security Versus Network Connectivity: A Framework For Addressing The Issues Facing The Air Force Medical Community, Franklin E. Cunningham Jr.

Theses and Dissertations

The Air Force has instituted Barrier Reef to protect its networks. The Air Force medical community operates network connections that are incompatible with Barrier Reef. To overcome this problem, OASD(HA) directed the Tri-Service Management Program Office (TIMPO) to develop an architecture that protects all military health systems and allows them to link with all three services and outside partners. This research studied the underlying networking issues and formed a framework based on data from network experts from the Air Force's medical centers and their base network organizations. The findings were compared TIMPO and a composite framework was developed that more …

Internet, World Wide Web, And Creativity, Keng Siau

Research Collection School Of Computing and Information Systems

The growth of the Internet has been the most astonishing technological and social phenomenon of the last decade of this century. In 1990 only a few academics had heard of it; now, more than 50 million people use it. By the turn of the century, that figure could be 100–200 million. So far, the network's only constant has been that the number of new users has doubled almost every 12–18 months. Most organizations have or will soon have Internet access. The popularity of Internet provides a tremendous opportunity for individuals and organizations to explore its features and services for electronic …

Two Approaches To Critical Path Scheduling For A Heterogeneous Environment, Guangxia Liu

Computer Science Theses & Dissertations

Advances in computing and networking technologies are making large scale distributed heterogeneous computing a reality. Multi-Disciplinary Optimization (MDO) is a class of applications that is being addressed under this paradigm. It consists of multiple heterogeneous modules interacting with each other to solve an overall design problem. An efficient implementation of such an application requires scheduling heterogeneous modules (with different computing and disk 1/0 requirements) on a heterogeneous set of resources (with different CPU, memory, disk IO specifications).

Given a set of tasks and a set of resources, an optimal schedule of the tasks on the resources is very hard to …

Smart Objects, Dumb Archives: A User-Centric, Layered Digital Library Framework, Kurt Maly, Michael L. Nelson, Mohammad Zubair

Computer Science Faculty Publications

Discusses digital libraries, interoperability, and interfaces to access them, and proposes one universal protocol for communication for simple archives based on the hypertext transfer protocol (http). Describes the creation of a special class of digital objects called buckets, archives based on a NASA collection, and a set of digital library services. (Author/LRW)

A Digital Library For The National Advisory Committee For Aeronautics, Michael L. Nelson

Computer Science Faculty Publications

We describe the digital library (DL) for the National Advisory Committee for Aeronautics (NACA), the NACA Technical Report Server (NACATRS). The predecessor organization for the National Aeronautics and Space Administration (NASA), NACA existed from 1915 until 1958. The primary manifestation of NACA's research was the NACA report series. We describe the process of converting this collection of reports to digital format and making it available on the World Wide Web (WWW) and is a node in the NASA Technical Report Server (NTRS). We describe the current state of the project, the resulting DL technology developed from the project, and the …

Synthetic Files: Enabling Low-Latency File I/O For Qos-Adaptive Applications, Dylan Mcnamee, Dan Revel, Calton Pu, David Steere, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Files are a tried and true operating system abstraction. They present a simple byte-stream model of I/O that has proven intuitive for application programmers and efficient for operating system builders. However, current file systems do not provide good support for adaptive continuous media (CM) applications - an increasingly important class of applications that exhibit complex access patterns and are particularly sensitive to variations in I/O performance. To address these problems we propose synthetic files. Synthetic files are specialized views of underlying regular files, and convert complex file access patterns into simple sequential synthetic file access patterns. Synthetic file construction can …

Architectural Optimization Of Digital Libraries, Aileen O. Biser

Computer Science Theses & Dissertations

This work investigates performance and scaling issues relevant to large scale distributed digital libraries. Presently, performance and scaling studies focus on specific implementations of production or prototype digital libraries. Although useful information is gained to aid these designers and other researchers with insights to performance and scaling issues, the broader issues relevant to very large scale distributed libraries are not addressed. Specifically, no current studies look at the extreme or worst case possibilities in digital library implementations. A survey of digital library research issues is presented. Scaling and performance issues are mentioned frequently in the digital library literature but are …

Multiple Streams Synchronization In Collaborative Multimedia Systems, Emilia Stoica

Computer Science Theses & Dissertations

With the recent increase of the communication bandwidth and processor power, new types of applications have emerged. Among them, there are multimedia application, in which users are able to control, combine, and manipulate different types of media, such as text, sound, video, computer graphics, and animation. A key requirement in any multimedia application is to synchronize the delivery of various media streams to the user. To achieve this, the sender has to provide the temporal relations between the streams as they are captured. Since the receiver uses this information in streams presentation, its accuracy is very important.

Our main contribution …

Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Recent advances in the Domain Name System (DNS) and the Dynamic Host Configuration Protocol (DHCP) have enabled a new approach to supporting mobile users: location independent naming. In this approach, machines use the same hostname from any internet location, but use an IP address that corresponds to their current location. We describe a protocol that implements location independent naming for nomadic computers, i.e., machines that do not need transparent mobility. Our protocol allows hosts to move across security domains, uses existing protocols, and preserves existing trust relationships. Therefore, it preserves the performance and security of normal IP for nomadic computers …