Digital Commons Network^™

Efficient Evaluation Of Continous Range Queries On Movng Objects, D.V. Kalashnikov, Sunil Prabhakar, Walid G. Aref, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.

A Case For Multi-Key Secure Video Proxy: Theory, Design And Implementation, Siu F. Yeung, John C.S. Lui, David K.Y. Yau

Department of Computer Science Technical Reports

No abstract provided.

Adaptive Predictive Congestion Control Of High-Speed Atm Networks, Sarangapani Jagannathan, Jayasree Talluri

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes an auto regressive moving average (ARMAX)-based adaptive control methodology to prevent congestion in high-speed asynchronous transfer mode (ATM) networks. Adaptive controller is developed to control traffic where sources adjust their transmission rates in response to the feedback information from the network switches. Specifically, the buffer dynamics at a given switch is modeled as a nonlinear discrete-time system and an ARMAX controller is designed so as to predict the explicit values of the transmission rates of the sources so as to prevent congestion. Tuning methods are provided for the unknown coefficients of the ARMAX model to estimate the …

Minimum Energy Paths For Reliable Communication In Multi-Hop Wireless Networks, Suman Banerjee, Archan Misra

Research Collection School Of Computing and Information Systems

Current algorithms for minimum-energy routing in wireless networks typically select minimum-cost multi-hop paths. In scenarios where the transmission power is fixed, each link has the same cost and the minimum-hop path is selected. In situations where the transmission power can be varied with the distance of the link, the link cost is higher for longer hops; the energy-aware routing algorithms select a path with a large number of small-distance hops. In this paper, we argue that such a formulation based solely on the energy spent in a single transmission is misleading --- the proper metric should include the total energy …

Energy Efficiency And Throughput For Tcp Traffic In Multi-Hop Wireless Networks, Sorav Bansal, Rajeev Gupta, Rajeev Shorey, Imran Ali, Ashu Razdan, Archan Misra

Research Collection School Of Computing and Information Systems

We study the performance metrics associated with TCP regulated traffic in multi-hop, wireless networks that use a common physical channel (e.g., IEEE 802.11). In contrast to earlier analyses, we focus simultaneously on two key operating metrics– the energy efficiency and the session throughput. Using analysis and simulations, we show how these metrics are strongly influenced by the radio transmission range of individual nodes. Due to tradeoffs between the individual packet transmission energy and the likelihood of retransmissions, the total energy consumption is a convex function of the number of hops (and hence, of the transmission range). On the other hand, …

Idmp: An Intradomain Mobility Management Protocol For Next-Generation Wireless Networks, Subir Das, Anthony Mcauley, Ashutosh Dutta, Archan Misra, Sajal K. Das

Research Collection School Of Computing and Information Systems

This paper describes a lightweight Intra-domain Management Protocol (IDMP) for managing mobility within a domain, commonly known as micro-mobility management, for next generation wireless networks. IDMP is modular and simple because it leverages existing protocols, such as Mobile IP or SIP (Session Initiated Protocol) as global mobility management, for locating roaming nodes. Unlike other proposed intra-domain mobility management schemes, IDMP uses two dynamically autoconfigured care-of addresses (CoAs) for routing the packets destined to mobile nodes. The global care-of address (GCoA) is relatively stable and identifies the mobile node’s attachment to the current domain, while the local care-of address (LCoA) changes …

Collaborative Problem Solving And Program Development Model, Joanna Defranco-Tommarello

Dissertations

A model to enhance collaborative problem solving and program development is presented. The collaborative model is a detailed cognitive model that takes into consideration the cognitive and social activities that occur during collaborative problem solving and program development. The cognitive activities required for collaborative problem solving and program development are identified and integrated into a six-stage model. An extensive literature review in the associated fields is presented to show the need for the model described in this dissertation. In addition, a comprehensive study of tools to support collaboration during problem solving and program development was also performed as well as …

Role Definition Language (Rdl): A Language To Describe Context-Aware Roles, Christopher P. Masone

Dartmouth College Undergraduate Theses

As wireless networks become more prevalent, a widening array of computational resources becomes available to the mobile user. Since not all users should have unrestricted access to these resources, a method of access control must be devised. In a context-aware environment, context information can be used to supplement more conventional password-based access control systems. We believe the best way to achieve this is through the use of Context-Aware Role-Based Access Control, a model in which permissions are assigned to entities called roles, each principal is a member of one or more roles, and a role's membership is determined using context …

An Evolving Approach To Learning In Problem Solving And Program Development : The Distributed Learning Model, Idania Espinosa

Theses

Technological advances are paving the way for improvements in many sectors of society. The US education system needs to undergo a transformation of existing pedagogical methods to maximize utilization of new technologies. Traditional education has primarily been teacher driven, lectured-based in one location. Advances in technology are challenging existing paradigms by developing tools and educational environments that reach diverse learning styles and surpass the boundaries of current teaching methods.

Distributed learning is an emerging paradigm today that has promise to contribute significantly to learning and improve overall academic success. This research first explores various systems that provide different modes of …

Building Trusted Paths For Web Browsers, Zishuang (Eileen) Ye

Dartmouth College Master’s Theses

The communication between the Web browser and the human user is one component of the server-client channel. It is not the user but the browser that receives all server information and establishes the secure connection. The browser's user interface signals, such as SSL lock, https protocol header et al., indicate whether the browser-server communication at the current moment is secure. Those user interface signals indicating the security status of browser should be clearly and correctly understood by the user.

A survey of modern Web browsers shows the information provided by current browsers is insufficient for users to make trust judgment. …

Towards Peer-To-Peer Semantic Web: A Distributed Environment For Sharing Semantic Knowledge On The Web, Madhan Arumugam, Amit P. Sheth, I. Budak Arpinar

Kno.e.sis Publications

The real value of Semantic Web vision can be demonstrated if people and applications can create and discover new and interesting knowledge and share this knowledge in a transparent manner similar to the way data is exchanged today. Therefore, we believe that Semantic Web will consist of a distributed environment of shared and interoperable ontologies, which have emerged as common formalisms for knowledge representation. The users will need to discover new ontologies, which are not known to them before and use them to either annotate the content or to formulate their information requests. This requires an environment that supports creating, …

Communicator-In-Chief: Presidential Use Of Television Past, Present, And Future, Jenna Wasson

Honors Theses

This thesis seeks to determine how television has changed as a communication medium for presidents over the past half century. An evaluation of the evolving ways presidents use television to communicate with and to build support from the American people has been conducted. Presidential communication strategies have been identified by drawing primarily from primary sources written by presidents and White House staff. Television technology and the television audience have changed over the years. Presidents have taken a more pro-active, aggressive role in their efforts to harness television for their own purposes. Why have these changes occurred? What impact have these …

Modeling Quality Of Service For Workflows And Web Service Processes, Jorge Cardoso, John A. Miller, Amit P. Sheth, Jonathan Arnold

Kno.e.sis Publications

Workflow management systems (WfMSs) have been used to support various types of business processes for more than a decade now. In workflows for e-commerce and Web-services applications, suppliers and customers define a binding agreement or contract between the two parties, specifying Quality of Service (QoS) items such as products or services to be delivered, deadlines, quality of products, and cost of services. The management of QoS metrics directly impacts the success of organizations participating in e-commerce. Therefore, when services or products are created or managed using workflows, the underlying workflow system must accept the specifications and be able to estimate, …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 8, May 2002, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Supporting Low-Latency Tcp-Based Media Streams, Ashvin Goel, Charles Krasic, Kang Li, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The dominance of the TCP protocol on the Internet and its success in maintaining Internet stability has led to several TCP-based stored media-streaming approaches. The success of these approaches raises the question whether TCP can be used for low-latency streaming. Low latency streaming allows responsive control operations for media streaming and can make interactive applications feasible. We examined adapting the TCP send buffer size based on TCP's congestion window to reduce application perceived network latency. Our results show that this simple idea significantly improves the number of packets that can be delivered within 200 ms and 500 ms thresholds.

Provisioning On-Line Games: A Traffic Analysis Of A Busy Counter-Strike Server, Wu-Chang Feng, Francis Chang, Wu-Chi Feng, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This paper describes the results of a 500 million packet trace of a popular on-line, multi-player, game server. The results show that the traffic behavior of this heavily loaded game server is highly predictable and can be attributed to the fact that current game designs target the saturation of the narrowest, last-mile link. Specifically, in order to maximize the interactivity of the game itself and to provide relatively uniform experiences between players playing over different network speeds, on-line games typically fix their usage requirements in such a way as to saturate the network link of their lowest speed players. While …

A Stream Database Server For Sensor Applications, Moustafa A. Hammad, Walid G. Aref, Ann C. Catlin, Mohamed G. Elfeky, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Joining Multiple Data Streams With Window Constraints, Moustafa A. Hammad, Walid G. Aref, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Poster: Provisioning On-Line Games: A Traffic Analysis Of A Busy Counter-Strike Server, Francis Chang, Wu-Chang Feng, Wu-Chi Feng, Jonathan Walpole

Computer Science Faculty Publications and Presentations

A poster that illustrates the client/server model employed by an multiplayer online game, focusing on bandwidth usage.

A Unique Examination Of The Buffer Overflow Condition, Terry Bruce Gillette

Theses and Dissertations

Buffer overflows have been the most common form of security vulnerability for the last ten years. More over, buffer overflow vulnerabilities enable the type of exploits that dominate remote network penetration. As our reliance on commercial third party software is critical in the current computing environment one must consider the question of how these vulnerabilities are discovered in released proprietary software. This thesis presents research focused on the fundamental issues surrounding the buffer overflow vulnerability. The objective is to analyze and understand the technical nature of this type of vulnerability and, on the basis of this, develop an efficient generic …

A Bdi Agent Software Development Process, Jeffrey M. Einhorn

Theses and Dissertations

As computer software continues to grow increasingly complex with each passing year, researchers continue to try and develop means to simplify software development. In this thesis, we propose a BDI agent software development process as the next evolution in software development. The goal of this research is to develop a process, which can be used to enable the creation of agent-based systems.

This thesis strives to present a practical software development process, which is useful to today's software engineer, by building upon current agent research and proven software engineering practices. Our BDI agent software development process is a systematic process, …

Mobile Commerce Applications In Supply Chain Management, Keng Siau, Zixing Shen

Research Collection School Of Computing and Information Systems

As wireless technologies evolve, the coming mobile revolution will bring dramatic and fundamental changes to supply chain management. When complete, the revolution will impact numerous facets of organizational life. It will provide important data in real time to assist decision makers, exert great influence on the ways businesses communicate and develop relationships with consumers and suppliers, and ultimately transform the way we manage the supply chain. This paper examines issues in integrating mobile commerce and supply chain management. The paper discusses issues such as the absence of killer applications, mobile device limitations, networking problems, infrastructure constraints, security concerns, and user …

Factors Influencing Adoption Of Mobile Computing, Wenli Zhu, Fiona Fui-Hoon Nah, Fan Zhao

Research Collection School Of Computing and Information Systems

The emergence of mobile computing combined with the increased popularity of the Internet is changing our daily lives. The increasing use of small portable computers, wireless networks and satellites un folds the new technology of mobile computing, which allows transmis sion of data to computers that are not physically linked to a network. As a result, people can communicate on the move. Mobile devices with new input and output methods and form factors are dramatically different from traditional desktop computers (Rodden et al., 1998). These technological changes make increasing demands on both the quality of user interface and the functionality …

A Case For Analytical Customer Relationship Management, Jaideep Srivastava, Jau-Hwang Wang, Ee Peng Lim, San-Yih Hwang

Research Collection School Of Computing and Information Systems

This paper describes how data analytics can be used to make various CRM functions like customer segmentation, communication targeting, retention, and loyalty much more effective. Also briefly describe the key technologies needed to implement analytical CRM, and are the organizational issues that must be carefully handled to make CRM a reality.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 7, April 2002, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Mobile Voice Over Ip (Mvoip): An Application-Level Protocol For Call Hand-Off In Real Time Applications, G. Ayorkor Mills-Tettey, David Kotz

Dartmouth Scholarship

This paper presents Mobile Voice Over IP, an application-level protocol to support terminal mobility in real-time applications such as voice over IP, on a wireless local area network. We describe our MVOIP implementation based on the ITU-T H.323 protocol stack, present experimental results on call hand-off latency, and discuss various implementation issues, including the task of quickly and accurately determining when call hand-off is necessary. We also discuss how MVOIP relates to other proposed mobility support schemes, and how it can be generalized to provide application-level mobility support in a wide range of real and non real-time applications.

Self-Similarity In Network Traffic, Francisco Chinchilla

Honors Theses

It is critical to properly understand the nature of network traffic in order to effectively design models describing network behavior. These models are usually used to simulate network traffic, which in turn are used to construct congestion control techniques, perform capacity planning studies, and/or evaluate the behavior of new protocols. Using the wrong models could lead to potentially serious problems such as delayed packet transmissions or an increase in packet drop rates.

Traditionally, packet arrivals were assumed to follow a Poisson arrival process. Although Poisson processes have several properties that make them easy to work with, they do not accurately …

Infopipes: An Abstraction For Multimedia Streaming, Andrew P. Black, Huang Jie, Rainer Koster, Jonathan Walpole, Calton Pu

Computer Science Faculty Publications and Presentations

To simplify the task of building distributed streaming applications, we propose a new abstraction for information flow – Infopipes. Infopipes make information flow primary, not an auxiliary mechanism that is hidden away. Systems are built by connecting predefined component Infopipes such as sources, sinks, buffers, filters, broadcasting pipes, and multiplexing pipes. The goal of Infopipes is not to hide communication, like an RPC system, but to reify it: to represent communication explicitly as objects that the program can interrogate and manipulate. Moreover, these objects represent communication in application-level terms, not in terms of network or process implementation.

A New Approach For Weighted Constraint Satisfaction, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

We consider the Weighted Constraint Satisfaction Problem which is an important problem in Artificial Intelligence. Given a set of variables, their domains and a set of constraints between variables, our goal is to obtain an assignment of the variables to domain values such that the weighted sum of satisfied constraints is maximized. In this paper, we present a new approach based on randomized rounding of semidefinite programming relaxation. Besides having provable worst-case bounds for domain sizes 2 and 3, our algorithm is simple and efficient in practice, and produces better solutions than some other polynomial-time algorithms such as greedy and …

Multi-Level Modeling Of Software On Hardware In Concurrent Computation, Joann M. Paul, Arne Suppe, Henele I. Adams, Donald E. Thomas

Research Collection School Of Computing and Information Systems

The fundamental modeling differences between hardware and software modeling can be thought of as reasoning about connectedness vs. reasoning about interleaved (shared) access to resources. A natural design hierarchy for physical systems is component-based because of the existence of a consistent basis for interconnect between design levels. However, performance modeling and design of concurrent, programmable systems require new ways of thinking about what it means to abstract detail, add detail and partition a model of software executing on hardware. We motivate frequency interleaving (FI) as a common simulation foundation for these systems because it resolves flow and partitioning with software …