OS and Networks Commons^™

Modeling The Transient Rate Behavior Of Bandwidth Sharing As A Hybrid Control System, Kang Li, Molly H. Shor, Jonathan Walpole, Calton Pu

Computer Science Faculty Publications and Presentations

This paper uses hybrid control to model a problem of computer network systems, the dynamic behavior of bandwidth sharing among competing TCP traffic. It has been well known in the computer network community that well-behaved (TCP-friendly) congestion control mechanisms are crucial to the robustness of the Internet. Congestion control determines the transmission rate for each flow. Right now, most TCP-friendly research focuses only on the average throughput behavior without considering how the data is sent out in the short-term (e.g. bursty or smooth). However, recent experimental results show that short-term rate adjustments can change the bandwidth sharing result. Therefore, it …

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. …

Moving Towards Massively Scalable Video-Based Sensor Networks, Wu-Chi Feng, Jonathan Walpole, Calton Pu, Wu-Chang Feng

Computer Science Faculty Publications and Presentations

Networking and computing technologies are becoming advanced enough to enable a wealth of diverse applications that will drastically change our everyday lives. Some past examples of these developments include the World Wide Web and wireless data networking infrastructures. As is quite obvious, the World Wide Web has enabled a fundamental change in the way many people deal with day-to-day tasks. Through the web, one can now make on-line reservations for travel, pay bills through on-line banking services, and view personalized on-line newscasts. More recently, developments in wireless technologies have enabled anywhere, anytime access to information over wireless medium. As wireless …

Development Of Objective-Oriented Components For Atm Networks Simulation With Emphasis On Switch Architecture, Boon Pin Tan

Student Works (2000-2009)

Asynchronous Transfer Mode (ATM) is considered to be the ground on which B-ISDN is to be built. It is the new generation of communication networks that are being deployed throughout the telecommunication industry. The basic functions of ATM switch are to direct cells from input port to output port and to buffer cell destined to the same output port from different input port. This project focuses on the development of an object-oriented simulator for simulation. The simulator is designed and implemented to ensure the correctness of routing within the switch fabric, fairness of switching and to guarantee quality of service …

Rate-Matching Packet Scheduler For Real-Rate Applications, Kang Li, Jonathan Walpole, Dylan Mcnamee, Calton Pu, David Steere

Computer Science Faculty Publications and Presentations

A packet scheduler is an operating system component that controls the allocation of network interface bandwidth to outgoing network flows. By deciding which packet to send next, packet schedulers not only determine how bandwidth is shared among flows, but also play a key role in determining the rate and timing behavior of individual flows. The recent explosion of rate and timing-sensitive flows, particularly in the context of multimedia applications, has focused new interest on packet schedulers. Next generation packet schedulers must not only ensure separation among flows and meet real-time performance constraints, they must also support dynamic fine-grain reallocation of …

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. …

Vpn-Data Center System Database, Thai Hwan Gan

Student Works (2000-2009)

Computer has advanced from high technology equipment that only by large company in the old days to office equipment that is essential in an office. In the world of computer, improvement on service provided and lock out competition is very important The quantity of service, speed of processing, productivity, efficiency and effectiveness is very vital. The purpose of this project is to create a database system to a company that provides services and selling computer product. Beside that, we also provide VPNVirtual Private Network for the company's branch to access and to update the database. This is to provide more …

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

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 …

Dynamic Bandwidth Allocation Using Neural-Fuzzy In Atm Network, Yan Sing Chua

Student Works (2000-2009)

Dynamic bandwidth allocation is becoming one of the crucial issues in the design and research in the computer network. This is due to the continuous increasing demand of intensive applications that require more bandwidth while retaining higher quality. Dynamic bandwidth allocation utilises the current network state information to optimise the bandwidth distribution. The state information can be gathered through prediction using past data and measurement on current state. Agility and flexibility of dynamic bandwidth allocation using Neural-Fuzzy has the advantage that it can adapt to the state changes of the network. ATM network carries heterogeneous traffic and this causes the …

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 …

Aspects Of Information Flow, Andrew P. Black, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Along with our colleagues at the Oregon Graduate Institute and Georgia Institute of Technology, we have recently been experimenting with real-rate systems, that is, systems that are required to move data from one place to another at defined rates, such as 30 items per second. Audio conferencing or streaming video systems are typical: they are required to deliver video or audio frames from a source (a server or file system) in one place to a sink (a display or a sound generator) in another; the frames must arrive periodically, with constrained latency and jitter. We have successfully built such systems …

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.

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 …

Vhdl Description For Ip Engine, Bathich Zeliall

Student Works (2000-2009)

Developing hardware support for network layer protocol processing is a very complex and demanding task. However. for optimal performance hardware acceleration can be required. To cope with the situation. this project present a high-level design approach. which targets the development of configurable and reusable components. Therefore it obtains the integration of advanced tools for the development of the IP Engine into the design environment. This process is illustrated based on a TCP/IP header analysis and validation component for which initial performance results are presented. The development of this Engine is embedded in an approach to develop flexible and configurable protocol …

Pc-Based Atm Network Simulator, Weei Shan Lai

Student Works (2000-2009)

Asynchronous Transfer Mode (ATM) has emerged as 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 project is divided into two parts: Part one: Study the concept of ATM and the important issues regarding it. Various existing simulators and applications on A TM are studied to plan for an up to date simulator. Part two: Develop a PC Based simulator. This is motivated by …

Supervised Adaptive Resonance Theory And Rules, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Supervised Adaptive Resonance Theory is a family of neural networks that performs incremental supervised learning of recognition categories (pattern classes) and multidimensional maps of both binary and analog patterns. This chapter highlights that the supervised ART architecture is compatible with IF-THEN rule-based symbolic representation. Specifi­cally, the knowledge learned by a supervised ART system can be readily translated into rules for interpretation. Similarly, a priori domain knowl­edge in the form of IF-THEN rules can be converted into a supervised ART architecture. Not only does initializing networks with prior knowl­edge improve predictive accuracy and learning efficiency, the inserted symbolic knowledge can also …

Qos Scalability For Streamed Media Delivery, Charles Krasic, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Applications with real-rate progress requirements, such as mediastreaming systems, are difficult to deploy in shared heterogenous environments such as the Internet. On the Internet, mediastreaming systems must be capable of trading off resource requirements against the quality of the media streams they deliver, in order to match wide-ranging dynamic variations in bandwidth between servers and clients. Since quality requirements tend to be user- and task-specific, mechanisms for capturing quality of service requirements and mapping them to appropriate resource-level adaptation policies are required. In this paper, we describe a general approach for automatically mapping user-level quality of service specifications onto resource …

Fine-Grain Period Adaptation In Soft Real-Time Environments, David Steere, Joshua Gruenberg, Dylan Mcnamee, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Reservation-based scheduling delivers a proportion of the CPU to jobs over a period of time. In this paper we argue that automatically determining and assigning this period is both possible and useful in general purpose soft real-time environments such as personal computers and information appliances. The goal of period adaptation is to select the period over which a job is guaranteed to receive its portion of the CPU dynamically and automatically. The choice of period represents a trade-off between the amount of jitter observed by the job and the overall efficiency of the system. Secondary effects of period include quantization …

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 …

Adaptive Resource Management Via Modular Feedback Control, Ashvin Goel, David Steere, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

A key feature of tomorrow’s operating systems and runtime environments is their ability to adapt. Current state of the art uses an ad-hoc approach to building adaptive software, resulting in systems that can be complex, unpredictable and brittle. We advocate a modular and methodical approach for building adaptive system software based on feedback control. The use of feedback allows a system to automatically adapt to dynamically varying environments and loads, and allows the system designer to utilize the substantial body of knowledge in other engineering disciplines for building adaptive systems. We have developed a toolkit called SWiFT that embodies this …

Wide-Area Incident Management System On The Internet, Kaan Ozbay, Pushkin Kachroo

Electrical & Computer Engineering Faculty Research

The incident management process consists of four sequential steps-incident detection, response, clearance and recovery. Each of these components comprises of a number of operations and coordinated decision-making between the agencies involved. The provision of computer based support tools for the personnel involved will help develop appropriate strategies and increase efficiency and expediency. Existing systems are developed on various traditional computing platforms. However, with the advent of World Wide Web and Internet based programming tools such as Java, it is now possible to develop platform independent decision support tools for the incident management agencies. Any agency will be able to use …

A Feedback-Driven Proportion Allocator For Real-Rate Scheduling, David Steere, Ashvin Goel, Joshua Gruenberg, Dylan Mcnamee, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper we propose changing the decades-old practice of allocating CPU to threads based on priority to a scheme based on proportion and period. Our scheme allocates to each thread a percentage of CPU cycles over a period of time, and uses a feedback-based adaptive scheduler to assign automatically both proportion and period. Applications with known requirements, such as isochronous software devices, can bypass the adaptive scheduler by specifying their desired proportion and/or period. As a result, our scheme provides reservations to applications that need them, and the benefits of proportion and period to those that do not. Adaptive …

Quality Of Service Semantics For Multimedia Database Systems, Jonathan Walpole, Charles Krasic, Ling Liu, David Maier, Calton Pu, Dylan Mcnamee, David Steere

Computer Science Faculty Publications and Presentations

Quality of service (QoS) support has been a hot research topic in multimedia databases, and multimedia systems in general, for the past several years. However, there remains little consensus on how QoS support should be provided. At the resource-management level, systems designers are still debating the suitability of reservation- based versus adaptive QoS management. The design of higher system layers is less clearly understood, and the specification of QoS requirements in domain-specific terms is still an open research topic. To address these issues, we propose a QoS model for multimedia databases. The model covers the specification of user-level QoS preferences …