Digital Communications and Networking Commons^™

Machine Learning Techniques For Network Analysis, Irfan Lateef

Dissertations

The network's size and the traffic on it are both increasing exponentially, making it difficult to look at its behavior holistically and address challenges by looking at link level behavior. It is possible that there are casual relationships between links of a network that are not directly connected and which may not be obvious to observe. The goal of this dissertation is to study and characterize the behavior of the entire network by using eigensubspace based techniques and apply them to network traffic engineering applications.

A new method that uses the joint time-frequency interpretation of eigensubspace representation for network statistics …

Communications With Spectrum Sharing In 5g Networks Via Drone-Mounted Base Stations, Liang Zhang

Dissertations

The fifth generation wireless network is designed to accommodate enormous traffic demands for the next decade and to satisfy varying quality of service for different users. Drone-mounted base stations (DBSs) characterized by high mobility and low cost intrinsic attributes can be deployed to enhance the network capacity. In-band full-duplex (IBFD) is a promising technology for future wireless communications that can potentially enhance the spectrum efficiency and the throughput capacity. Therefore, the following issues have been identified and investigated in this dissertation in order to achieve high spectrum efficiency and high user quality of service.

First, the problem of deploying DBSs …

Multiframe Coded Computation For Distributed Uplink Channel Decoding, Brinell F. Monteiro

Theses

The latest 5G technology in wireless communication has led to an increasing demand for higher data rates and low latencies. The overall latency of the system in a cloud radio access network is greatly affected by the decoding latency in the uplink channel. Various proposed solutions suggest using network function virtualization (NFV). NFV is the process of decoupling the network functions from hardware appliances. This provides the exibility to implement distributed computing and network coding to effectively reduce the decoding latency and improve the reliability of the system. To ensure the system is cost effective, commercial off the shelf (COTS) …

Preemptive Efficient Queueing For Scheduling Deadline-Bound Data Center Flows, Vinaykrishna Gopalakrishna

Theses

This thesis introduces a new deadline aware flow scheduling scheme called Preemptive Efficient Queuing (PEQ). Unlike other schemes which use policies like EDF, SJF or fair share, this scheme aims to procrastinate flows as much as they can afford to, while keeping with their deadlines. Thereby, PEQ prioritizes more urgent flows that have shorter time to procrastinate, or cushion time. Results of PEQ are compared with state-of-the-art schemes for the transport of data-center flows, such as Preemptive Distributed Quick (PDQ) and Deadline-Driven Delivery (D³). The results show that PEQ outperforms D³ and PDQ. We identify results …

Source-Channel Coding For Coordination Over A Noisy Two-Node Network, Sarah A. Obead

Theses

Recently, the concept of coordinating actions between distributed agents has emerged in the information theory literature. It was first introduced by Cuff in 2008 for the point-to-point case of coordination. However, Cuff’s work and the vast majority of the follow-up research are based on establishing coordination over noise-free communication links. In contrast, this thesis investigates the open problem of coordination over noisy point-to-point links. The aim of this study is to examine Shannon’s source-channel separation theorem in the context of coordination. To that end, a general joint scheme to achieve the strong notion of coordination over a discrete memoryless channel …

Retransmission Strategies For Moving Networks Over Ricean Fading Channels, Alex Ruiz Lee

Theses

The problem of designing retransmission protocols based on Hybrid Automatic Repeat reQuest (HARQ) for moving networks over Ricean fading channels has been considered. The scenario of interest consists of one receiver traveling at a given speed while connected to a wireless network based on OFDM (e.g., WiMax) through several base stations located along the path. Five different retransmission protocols that combine HARQ with handover between adjacent base stations are considered. Their performance in terms of number of retransmissions per packet via numerical simulations, considering both frequency selective and nonselective channels are presented. The results obtained show the relevant advantage that …

Proactive Methods For Measurement Of Available Bandwidth And Link Capacity, Khondaker Musfakus Salehin

Theses

With the continuous expansion of network infrastructure and deployment of applications sensitive to Quality-of-Service, network measurement plays a major role in both network planning and management. Accurate measurement of various network parameters, e.g., available bandwidth, link capacity, delay, packet loss and jitter, provides a positive impact for effective traffic engineering, Quality-of-Service (QoS) routing, optimization of end-to-end transport performance, and link capacity planning. For network measurement, there exists several proactive estimation tools based on either probe-gap model or probe-rate model that estimate path related attributes. Most of these tools that have been implemented can measure tight-link capacity (smallest available bandwidth) and/or …

Location Estimation In A 3d Environment Using Radio Frequency Identification Tags, Adwitiya Akash Jain

Theses

RFID tag location estimation in a 3D environment is investigated. The location of the tag with unknown coordinates can be estimated with certain accuracy. However, accuracy can be improved using the knowledge based on measurement of additional reference tags with known location. This thesis studies the mathematical formulation and practical realization of location sensing using RFID tags.

Deviating from the standard use of RFID technology which employs one tag reader to identify the presence of tag, here multiple tag readers with known location are used to estimate the physical location of an individual tag, with/without the help of few reference …

New Hybrid Automatic Repeat Request (Harq) Scheme For 4x4 Mimo System, Based On The Extended Alamouti Quasi-Orthogonal Space-Time Bloc Coding (Q-Stbc), In Invariant And Variant Fading Channel, Jordi Ferrer Torras

Theses

A new Hybrid Automatic Repeat reQuest (HARQ) combining scheme for a 4x4 Multiple Input Multiple Output (MIMO) system in invariant and variant fading channel conditions is proposed and analized. Based on the Extended Alamouti Quasi-orthogonal Space-Time Block Coding (Q-STBC), the use of the so-called Alternative Matrices for transmission, depending on the Channel State Information (CSI) received as feedback, is compared to other existing solutions.

Sign changes and permutations in the retransmission sequences allow reducing the interference while exploiting the spatial diversity to introduce some gain in the signal power. The best transmission order is selected by the Determinant Criterion, which …

New Hybrid Automatic Repeat Request (Harq) Combining With Space Time Block Coding (Stbc) In Invariant And Variant Fading Channel, Guillem Ernest Malagarriga Vilella

Theses

Hybrid Automatic Repeat reQuest (HARQ) combining for space time block coding Multiple Input Multiple Output (MIMO) system consisting of N transmit antennas and M receive antennas (NxM) in a time invariant channel and in a time varying channel is proposed and its performance is analyzed. Based on the measured channel matrix, the receiver chooses the best retransmission order and communicated it to the transmitter.

The scheme, where this algorithm is performed, is a combination of a precombining HARQ scheme and the Multiple Alamouti Space-Time Block Coding (MASTBC), which is suitable for more than 2 transmit antennas. The combination of this …

An Analytical Model Of Mac Protocol Dependant Power Consumption In Multi-Hop Ad Hoc Wireless Sensor Networks, Komlan Egoh

Theses

Power efficiency is the most constraining requirement for viable operation of battery-powered networked sensors. Conventionally, dynamic power management (DPM) is used to put sensor nodes into different states such as active, idle, and sleep, each consuming a certain level of power. Within the active state, communication operational states, such as receive and transmit consume different levels of nodal power. This thesis shows how DPM states and protocol operational states can be combined into a single stochastic model to finely evaluate the power consumption performance of a medium access control (MAC) protocol. The model is formulated as a semi-Markov decision process …

Evaluation Of Coding Scheme For Mimo Radar, Suresh Kumar Harikrishnan

Theses

Multiple Input Multiple Output (MIMO) antenna systems have shown a great potential for wireless communication. These systems support high capacity, increased diversity and interference suppression. Recently it has been proposed MIMO constellations for Radar. MIMO Radar is not only a new research field, but also a very promising approach in terms of overcoming Radar Cross Section (RCS) fluctuations with diversity. This thesis explores the potential of coding schemes for MIMO Radar.

The ambiguity functions measures related to MIMO Radar are used to evaluate how much diversity gain can be coherently achieved with certain coding schemes. The results of this analysis …

Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya

Theses

A wireless ad-hoc network is a cooperative communication network deployed with a specific purpose. It is characterized by dynamically changing topology with no fixed infrastructure which exhibits a perfectly vulnerable state for a number of different kinds of attacks.

This thesis proposes a novel technique of achieving security in wireless mobile ad hoc networks by integrating a simple clustering and a voting mechanism together. The purpose of forming a cluster is to facilitate security in the network and the voting is performed to support the decision making process in the cluster. A procedure of forming small homogenous clusters throughout the …

Ultra Wideband Communication Link, Preeti Singh

Theses

Ultra-wideband communication (UWB) has been a topic of extensive research in recent years especially for its short-range communication and indoor applications. The preliminary objective of the project was to develop a description and understanding of the basic components of the communication link at microwave frequencies in order to achieve the primary objective of establishing a communication setup at a bandwidth of 2.5 GHz for testing Ultra Wideband (UWB) antennas. This was achieved with the aid of commercially available optical system which was modified for the purpose. Beginning with the generation of baseband narrow pulses with energy spanning over a broad …

Adaptive Turn-Prohibition Routing Algorithm For The Networks Of Workstations, Amey Bhaskar Shevtekar

Theses

Deadlock occurrence is a critical problem for any computer network. Various solutions have been proposed over last two decades to solve problem of deadlocks in networks using different routing schemes, like up/down routing algorithm used in Myrinet switches. However, most of existing approaches for deadlock-free routing either try to eliminate any possibility of deadlock occurrence, which can result in putting extra restrictions on the routing in the networks or put no restrictions on routing, which leads to other approach namely deadlock recovery. In this thesis emphasis is on developing hybrid approach for routing in wormhole networks, wherein some prohibition is …

Low Interference Routing For Wireless Ad-Hoc Networks, Mohit Gupta

Theses

In this thesis the primary focus is on the problem of interference between messages. The thesis discusses why the messages are blocked in a system? How adding a message impacts the cost of all other available links, which can be established in the system.

This thesis analyzes how the availability of channels, increase in number of nodes and increase in the transmission range help in increasing the number of messages that can be handled in the network. It is also analyzes how critical is the selection of the maximum transmission range MTR, transmission range TR and required transmission range RTR. …

Intrusion Detection System For Ad Hoc Mobile Networks Using Neighborhood Watch Theory, Ramani Rajagopalan

Theses

This study describes several experiments to simulate and study temperature sensor networks. The ultimate goal of this study is to accurately predict a temperature sensor failure in a sensor network, using Network Neighborhood Watch theory. Simulated temperature measurements are used to compare the results of accuracy, and quickness in detecting a failure in a malfunctioning sensor node. This is done by changing the intervals between temperature sampling, by considering different rates of temperature raise, as well as varying the number of nodes in the network neighborhood (deployment density). The thesis studies the threshold for temperature sensor failure by computing a …

Hop-Limited Routing For Multihop Cellular Networks, Cem Dincer

Theses

In recent years, conventional cellular systems have experienced evolution in fields of data oriented services. During this period, the requirement for high data-rate stimulated new research proposals, which resulted in a new architecture: Multihop Cellular Networks (MCN), where multihop structure enables mobile stations to forward packets from other mobile stations to the base station on the uplink, and in turn, forward packets to other mobile stations from the base station on the downlink. In this thesis, a new routing algorithm is introduced for MCNs in order to limit the number of hops between the base station and the mobile stations …

Reduction Of False Positives In Fault Detection System Using A Low Pass Data Filter, Ranjit Salunkhe

Theses

Network traffic is bursty in nature and exhibits the property of self-similarity, the degree of which is measured by the Hurst parameter. Now, in any network there is always the possibility of the occurrence of fault traffic that can be caused due to faults or malfunction of a network component. Fault Detection Systems that check for traffic anomalies can trigger off an alert on the detection of any traffic behavior that deviates from normal. Such deviation is usually caused when a fault occurs. But in network traffic sudden bursts may occur due to the inherent behavior of a network application. …

Mutual Interference Investigation Of Cebus And X-10 Powerline Signaling, Sajid Pallithotungal

Theses

Powerline control signaling using CEBus has great potential towards inexpensive home automation. CEBus transmits at 10 kBps using spread spectrum in the 100-400 kHz band while X-l0 sends 60 Bps using bursts of 120 kHz carrier on the power line. However, these two signals may destructively interfere when present simultaneously. X-10 is narrow band and interferes with the CEBus spread spectrum signal. This thesis looks into the mutual interference patterns of Power Line CEBus communication in the presence of X-l0 module signaling and visa versa. The investigation encompasses a series of tests and measurements on a Power Line CEBus-X10 test …

Teaching Upper Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Julian M. Scher, Michael Bieber, Murray Turoff

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

Teaching Lower Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Fadi Deek, Maura Deek, James Geller, Ajaz R. Rana

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

Eies 2 : A Distributed Architecture For Supporting Group Work, Computerized Conferencing & Communications Center, James Whitescarver, Robert M. Czech, Sreenivas Reddy, Ajaz R. Rana, Murray Turoff

Computerized Conferencing and Communications Center Reports

The Computerized Conferencing Center (CCCC) at New Jersey Institute of Technology (NJIT) has been researching on-line group communications for 17 years by developing and studying tools to advance the "collective intelligence". The Electronic Information Exchange System 2 (EIES2) provides a research, development and operational environment for distributed computer supported cooperative work (CSCW) systems. The EIES 2 distributed Smalltalk processor provides for rapid prototyping and implementation of muti-media CSCW facilities in the network environment. The Smalltalk support of the object model, and meta-language properties make it ideally suited for incremental development CSCW applications. The EIES2 communication environment supports a decentralized network …

Functional Requirements For Computer Conferencing And Computer Mediated Communications, Computerized Conferencing & Communications Center, Murray Turoff, Starr Roxanne Hiltz, James Whitescarver, John Foster

Computerized Conferencing and Communications Center Reports

This paper is a compilation of the desirable functionality for Computerized Conferencing Systems. It is based upon the research and evaluation activities of the Conferencing Center at NJIT and can he considered as an overall set of objectives for the development of its Conferencing Systems.

Teaching In A Virtual Classroom : Volume 2 Of A Virtual Classroom On Eies : Final Evaluation Report, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz

Computerized Conferencing and Communications Center Reports

A Virtual Classroom is a teaching and learning environment located within a computer-mediated communication system. As a teaching environment, it provides a set of tools, strengths, and limitations which are available to an instructor for delivering course materials and structuring learning experiences. Its characteristics are merely potentials, just as the empty classroom with its chalkboards and desks awaits the efforts and creativity of the instructor and the students to make it "come alive."

This is the second volume of the final research report on experiences with the prototype of a Virtual Classroom system constructed and operated on EIES, the Electronic …

Learning In A Virtual Classroom : Volume 1 Of A Virtual Classroom On Eies : Final Evaluation Report, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz

Computerized Conferencing and Communications Center Reports

The Virtual Classroom [TM] is a system for learning and communicating via connected computers. Students in the Virtual Classroom share their thoughts, questions and reactions with professors and classmates using computers equipped with specially designed software. The software enables students to send and receive messages, interact with professors and classmates, read and comment on lecture material, take tests and receive feedback, and more, without having to attend scheduled classes. Learning can take place at any location in the world and at any time of the day using a computer on campus, at home or in the workplace.

The primary goal …

The Virtual Classroom: Building The Foundations, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz

Computerized Conferencing and Communications Center Reports

This is a report on the first year of a three-year project concerned with the development and assessment of new types of software capabilities designed to support university level courses. A "virtual classroom" or "university without walls" is being created within a computerized conferencing system. During the first year of the project, students in twelve courses at three universities completed part or all of their coursework online. Pre and post-course questionnaires and automatic monitoring of their computer-mediated communications are the main sources of data. Independent variables include the expectations and attributes of the individual students; characteristics of the particular hardware …

Moderating Online Conferences, Revised Manuscript, Computerized Conferencing & Communications Center, Elaine B. Kerr

Computerized Conferencing and Communications Center Reports

While considerable lore has accumulated about effective leadership techniques for groups interacting electronically, until now it has not been systematically presented. This material is culled from the experiences of those who have moderated past online conferences, the knowledge common to the EIES User Consultants, and observed behavior from thousands of conferences convened on EIES in the past. While this is a system-specific guide, the general principles ought to be generalizable to other systems, with different structures for group discussion.

Robert Burns put it well:
The best laid schemes o' mice and men
Gang aft a-gley;
An' lea'e us nought but …

Integrating Working At Home With Information Systems Management, Computerized Conferencing & Communications Center, Joseph C. Schuh

Computerized Conferencing and Communications Center Reports

The history of computerization has its origin in the automation of manual processes - searching out the segments that could be put on a computer. The intended result was that the entire job would be done faster and cheaper. Thus, current computer-based information systems tend to make more efficient use of computers than people. The management function, on the other hand, often seems to focus on competitive skills and salesmanship rather than on the ability to attract and hold talented people. But, such impersonal factors that have driven management practices are changing. There has been a complete reversal in the …

Determinants Of Acceptance Of Computer Mediated Communication System, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Elaine B. Kerr, Kenneth Johnson, Murray Turoff

Computerized Conferencing and Communications Center Reports

Acceptance of Computer-Mediated communication Systems (CMCS) by managers and professionals corresponds to its incorporation into their daily patterns of communication and work. Acceptance includes at least three inter-related dimensions: amount of use, subjective satisfaction with the process of using the system, and a perception that system use has positive impacts upon productivity.

Pre-use and follow-up questionnaires were distributed to 150- 250 new users of four different CMCS. Three are conferencing systems, designed to support "group work." They differ in terms of comprehensiveness or complexity of design, and size and nature of the user communities; COM/KOM, a Swedish system with mostly …