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Digital Communications and Networking

2009

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Articles 1 - 30 of 59

Full-Text Articles in Computer Engineering

Interactions, Competition And Innovation In A Service-Oriented Internet: An Economic Model, Zhi-Li Zhang, Papak Nabipay, Andrew Odlyzko, Roch A. Guérin Dec 2009

Interactions, Competition And Innovation In A Service-Oriented Internet: An Economic Model, Zhi-Li Zhang, Papak Nabipay, Andrew Odlyzko, Roch A. Guérin

Departmental Papers (ESE)

This paper presents a new economic approach for studying competition and innovation in a complex and highly interactive system of network providers, users, and suppliers of digital goods and services (i.e., service providers). It employs Cournot and Bertrand games to model competition among service providers and network providers, respectively, and develops a novel unified model to capture the interaction and competition among these players in a “service-oriented” Internet. Incentives for service and network innovation are studied in this model.


On The Feasibility And Efficacy Of Protection Routing In Ip Networks, Kin-Wah (Eric) Kwong, Lixin Gao, Roch A. Guérin, Zhi-Li Zhang Dec 2009

On The Feasibility And Efficacy Of Protection Routing In Ip Networks, Kin-Wah (Eric) Kwong, Lixin Gao, Roch A. Guérin, Zhi-Li Zhang

Departmental Papers (ESE)

With network components increasingly reliable, routing is playing an ever greater role in determining network reliability. This has spurred much activity in improving routing stability and reaction to failures, and rekindled interest in centralized routing solutions, at least within a single routing domain. Centralizing decisions eliminates uncertainty and many inconsistencies, and offers added flexibility in computing routes that meet different criteria. However, it also introduces new challenges; especially in reacting to failures where centralization can increase latency. This paper leverages the flexibility afforded by centralized routing to address these challenges. Specifically, we explore when and how standby backup forwarding options ...


Egoviz – A Mobile Based Spatial Interaction System, Keith Gardiner, Junjun Yin, James Carswell Dec 2009

Egoviz – A Mobile Based Spatial Interaction System, Keith Gardiner, Junjun Yin, James Carswell

Articles

This paper describes research carried out in the area of mobile spatial interaction and the development of a mobile (i.e. on-device) version of a simulated web-based 2D directional query processor. The TellMe application integrates location (from GPS, GSM, WiFi) and orientation (from digital compass/tilt sensors) sensing technologies into an enhanced spatial query processing module capable of exploiting a mobile device’s position and orientation for querying real-world 3D spatial datasets. This paper outlines the technique used to combine these technologies and the architecture needed to deploy them on a sensor enabled smartphone (i.e. Nokia 6210 Navigator). With ...


Quality-Driven Cross Layer Design For Multimedia Security Over Resource Constrained Wireless Sensor Networks, Wei Wang Dec 2009

Quality-Driven Cross Layer Design For Multimedia Security Over Resource Constrained Wireless Sensor Networks, Wei Wang

Theses, Dissertations, & Student Research in Computer Electronics & Engineering

The strong need for security guarantee, e.g., integrity and authenticity, as well as privacy and confidentiality in wireless multimedia services has driven the development of an emerging research area in low cost Wireless Multimedia Sensor Networks (WMSNs). Unfortunately, those conventional encryption and authentication techniques cannot be applied directly to WMSNs due to inborn challenges such as extremely limited energy, computing and bandwidth resources. This dissertation provides a quality-driven security design and resource allocation framework for WMSNs. The contribution of this dissertation bridges the inter-disciplinary research gap between high layer multimedia signal processing and low layer computer networking. It formulates ...


Cyber Influence, William Hutchinson Dec 2009

Cyber Influence, William Hutchinson

Australian Information Warfare and Security Conference

This paper explores influence in the cyber-world and the ability and effectiveness of influence campaigns in this medium. It examines the possibilities of influence in the online world as examines the potential of mobile technologies in this area. The contentious link between influence and behavioural change is investigated. Counterinfluence in the context of radicalisation is also looked at. Whilst it is inevitable that the digital medium is and will be used for influence campaigns and will be influential regardless if there are concerted ‘campaigns’ or not, it effects in terms of behavioural change are still open to question.


Safeguarding Australia From Cyber-Terrorism:A Proposed Cyber-Terrorism Scada Risk Framework For Industry Adoption, Christopher Beggs, Matthew Warren Dec 2009

Safeguarding Australia From Cyber-Terrorism:A Proposed Cyber-Terrorism Scada Risk Framework For Industry Adoption, Christopher Beggs, Matthew Warren

Australian Information Warfare and Security Conference

Terrorist groups are currently using information and communication technologies (ICTs) to orchestrate their conventional physical attacks. More recently, terrorists have been developing a new form of capability within the cyber-arena to coordinate cyber-based attacks. This paper identifies that cyber-terrorism capabilities are an integral, imperative, yet under-researched component in establishing, and enhancing cyber-terrorism risk assessment models for SCADA systems. This paper is an extension of work previously published by Beggs and Warren 2008, it presents a high level overview of a cyber-terrorism SCADA risk framework that has been adopted and validated by SCADA industry practitioners. The paper proposes a managerial framework ...


A Bandwidth Aware Modification To The Dsr Routing Protocol For Wireless Mesh Networks, Mustafa Ramadhan, Mark Davis Dec 2009

A Bandwidth Aware Modification To The Dsr Routing Protocol For Wireless Mesh Networks, Mustafa Ramadhan, Mark Davis

Conference papers

This work proposes a bandwidth aware cross-layer modification to the DSR routing protocol. We include the Access Efficiency Factor (AEF) parameter in addition to the hop-count in the routing discovery mechanism. AEF is a measure to the local availability of bandwidth at a node. Employing the AEF as a metric in the routing discovery mechanism attempts to avoid routing through a congested area in the network. In this modification, we impose a limit on the hop-count in order to control the delay time in the network. The path selection procedure operates by finding a path with the highest minimum AEF ...


The Convergence Of Broadcasting And Telephony: Legal And Regulatory Implications, Christopher S. Yoo Dec 2009

The Convergence Of Broadcasting And Telephony: Legal And Regulatory Implications, Christopher S. Yoo

Faculty Scholarship at Penn Law

This article, written for the inaugural issue of a new journal, analyzes the extent to which the convergence of broadcasting and telephony induced by the digitization of communications technologies is forcing policymakers to rethink their basic approach to regulating these industries. Now that voice and video are becoming available through every transmission technology, policymakers can no longer define the scope of regulatory obligations in terms of the mode of transmission. In addition, jurisdictions that employ separate agencies to regulate broadcasting and telephony must reform their institutional structures to bring both within the ambit of a single regulatory agency. The emergence ...


Session Initiation Protocol Server Implementation For Linksys Routers, Matthew Duder Dec 2009

Session Initiation Protocol Server Implementation For Linksys Routers, Matthew Duder

Computer Science and Software Engineering

Session Initiation Protocol (SIP) is a signaling protocol used for network-based media interaction. SIP Servers are required to process and forward requests and responses between end clients. Once connection setup is complete, the end clients utilize some other protocol (such as Real-Time Transport Protocol) to complete their task.

Such a server may be implemented and installed on routers. Unlike the SIP protocol, however, router development currently remains without standards. For this project, Linux-based residential-grade routers had their kernels replaced with an open source version. This allowed for installation of open-source development, such as a SIP server implementation.

This project led ...


Grating Lobe Reduction In Aperiodic Linear Arrays Of Physically Large Antennas, William C. Barott, Paul G. Steffes Dec 2009

Grating Lobe Reduction In Aperiodic Linear Arrays Of Physically Large Antennas, William C. Barott, Paul G. Steffes

Publications

We present performance bounds obtained from the optimization of the sidelobe levels of aperiodic linear arrays. The antennas comprising these arrays are large compared to the distance between neighboring antennas, a case not addressed in previously published work. This optimization is performed in pattern-space and is applicable over a wide range of scan angles. We show that grating lobes can be suppressed even when the elemental antennas are several wavelengths in size, provided that the ratio of the antenna size to the average spacing between the antenna center-points does not exceed 80%.


A Model To Study Cyber Attack Mechanics And Denial-Of-Service Exploits Over The Internet's Router Infrastructure Using Colored Petri Nets, Lawrence M. Healy Nov 2009

A Model To Study Cyber Attack Mechanics And Denial-Of-Service Exploits Over The Internet's Router Infrastructure Using Colored Petri Nets, Lawrence M. Healy

Master's Theses and Doctoral Dissertations

The Internet‟s router infrastructure, a scale-free computer network, is vulnerable to targeted denial-of-service (DoS) attacks. Protecting this infrastructure‟s stability is a vital national interest because of the dependence of economic and national security transactions on the Internet. Current defensive countermeasures that rely on monitoring specific router traffic have been shown to be costly, inefficient, impractical, and reactive rather than anticipatory.

To address these issues, this research investigation considers a new paradigm that relies on the systemic changes that occur during a cyber attack, rather than individual router traffic anomalies. It has been hypothesized in the literature that systemic ...


Product Life Cycle Theory And The Maturation Of The Internet, Christopher S. Yoo Nov 2009

Product Life Cycle Theory And The Maturation Of The Internet, Christopher S. Yoo

Faculty Scholarship at Penn Law

Much of the recent debate over Internet policy has focused on the permissibility of business practices that are becoming increasingly common, such as new forms of network management, prioritization, pricing, and strategic partnerships. This Essay analyzes these developments through the lens of the management literature on the product life cycle, dominant designs, technological trajectories and design hierarchies, and the role of complementary assets in determining industry structure. This analysis suggests that many of these business practices may represent nothing more than a reflection of how the nature of competition changes as industries mature. This in turn suggests that network neutrality ...


Resource Management And Optimization In Wireless Mesh Networks, Xiaowen Zhang Nov 2009

Resource Management And Optimization In Wireless Mesh Networks, Xiaowen Zhang

FIU Electronic Theses and Dissertations

A wireless mesh network is a mesh network implemented over a wireless network system such as wireless LANs. Wireless Mesh Networks(WMNs) are promising for numerous applications such as broadband home networking, enterprise networking, transportation systems, health and medical systems, security surveillance systems, etc. Therefore, it has received considerable attention from both industrial and academic researchers. This dissertation explores schemes for resource management and optimization in WMNs by means of network routing and network coding. In this dissertation, we propose three optimization schemes. (1) First, a triple-tier optimization scheme is proposed for load balancing objective. The first tier mechanism achieves ...


Adaptive Multicast On Mobile Ad Hoc Networks Using Tree-Based Meshes With Variable Density Of Redundant Paths, Sangman Moh, Sang Jun Lee, Chansu Yu Nov 2009

Adaptive Multicast On Mobile Ad Hoc Networks Using Tree-Based Meshes With Variable Density Of Redundant Paths, Sangman Moh, Sang Jun Lee, Chansu Yu

Electrical Engineering & Computer Science Faculty Publications

Multicasting has been extensively studied for mobile ad hoc networks (MANETs) because it is fundamental to many ad hoc network applications requiring close collaboration of multiple nodes in a group. A general approach is to construct an overlay structure such as multicast tree or mesh and to deliver a multicast packet to multiple receivers over the overlay structure. However, it either incurs a lot of overhead (multicast mesh) or performs poorly in terms of delivery ratio (multicast tree). This paper proposes an adaptive multicast scheme, called tree-based mesh with k-hop redundant paths (TBM k ), which constructs a multicast tree ...


Online Optimization Of 802.11 Mesh Networks, Theodoros Salonidis, Georgios Sotiropoulos, Roch A. Guérin, Ramesh Govindan Oct 2009

Online Optimization Of 802.11 Mesh Networks, Theodoros Salonidis, Georgios Sotiropoulos, Roch A. Guérin, Ramesh Govindan

Departmental Papers (ESE)

802.11 wireless mesh networks are ubiquitous, but suffer from severe performance degradations due to poor synergy between the 802.11 CSMA MAC protocol and higher layers. Several solutions have been proposed that either involve significant modifications to the 802.11 MAC or legacy higher layer protocols, or rely on 802.11 MAC models seeded with off-line measurements performed during network downtime.

We introduce a technique for online optimization of 802.11 wireless mesh networks using rate control at the network layer. The technique is based on a lightweight model that characterizes the feasible rates region of an operational 802 ...


Real-World Performance Of Current Proactive Multi-Hop Mesh Protocols, M. Abolhasan, Brett Hagelstein, Jerry Chun-Ping Wang Oct 2009

Real-World Performance Of Current Proactive Multi-Hop Mesh Protocols, M. Abolhasan, Brett Hagelstein, Jerry Chun-Ping Wang

Faculty of Informatics - Papers (Archive)

The proliferation of mesh or ad hoc network protocols has lead to a push for protocol standardisation. While there are a number of both open-source and proprietary mesh routing protocols being developed, there is only a small amount of literature available that shows relative strengths and weaknesses of different protocols. This paper investigates the performance of a number of available routing protocols using a real-world testbed. Three routing protocols - Optimised Link State Routing (OLSR), Better Approach To Mobile Ad hoc Network (B.A.T.M.A.N.) and BABEL - were chosen for this study. Our investigations focus on the multi-hopping ...


Always Acyclic Distributed Path Computation, Saikat Ray, Roch A. Guérin, Kin Wah (Eric) Kwong, Rute Sofia Oct 2009

Always Acyclic Distributed Path Computation, Saikat Ray, Roch A. Guérin, Kin Wah (Eric) Kwong, Rute Sofia

Departmental Papers (ESE)

Distributed routing algorithms may give rise to transient loops during path recomputation, which can pose significant stability problems in high-speed networks. We present a new algorithm, Distributed Path Computation with Intermediate Variables (DIV), which can be combined with any distributed routing algorithm to guarantee that the directed graph induced by the routing decisions remains acyclic at all times. The key contribution of DIV, besides its ability to operate with any routing algorithm, is an update mechanism using simple message exchanges between neighboring nodes that guarantees loop-freedom at all times. DIV provably outperforms existing loop-prevention algorithms in several key metrics such ...


Graphic Design - 2009 Career Day Visit - The University Of Tennessee, Gregory Keith Bartley Jr. Sep 2009

Graphic Design - 2009 Career Day Visit - The University Of Tennessee, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

This is a graphic design piece that I constructed for a Career Day visit hosted by our department. Most, if not all of the design and artwork was performed in Photoshop using advanced Layering and Masking Techniques, taking advantage of silhouettes from pictures supplied to me by undergraduate students in the program of interest. This poster was printed at the largest size our University Graphic Printer would allow, so it is meant to be viewed at a very large resolution, so extensive panning may be required when viewing it on a standard computer screen.


User Security Behavior On Wireless Networks: An Empirical Study, Tim Chenoweth, Robert Minch, Sharon Tabor Sep 2009

User Security Behavior On Wireless Networks: An Empirical Study, Tim Chenoweth, Robert Minch, Sharon Tabor

Robert P. Minch

Wireless networks are rapidly becoming ubiquitous but are often insecure and leave users responsible for their own security. We empirically study whether users are successfully securing their client computers when using wireless networks. Automated techniques are used that scan users' machines after they associate with a university wireless network. This determines whether a firewall is being used and what TCP ports are open. Results show that over 9% of 3,331 unique computers scanned were not using a properly configured firewall. In addition, almost 9% had at least one TCP port open, with almost 6% having open ports with significant ...


Binary Usenet Application, Alexander J. Patterson Sep 2009

Binary Usenet Application, Alexander J. Patterson

Masters Projects

ANZBC software was written as a prototype to download small‐encoded files form Usenet servers. This software allows anything from a text document to a HD movie to be downloaded and decoded into a single file. Often this is a single file that is split into multiple small files and then compressed.


Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle Sep 2009

Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle

Conference papers

This paper discusses a new approach to ‘watermarking’ digital signals using linear frequency modulated or ‘chirp’ coding. The principles underlying this approach are based on the use of a matched filter to provide a reconstruction of a chirped code that is uniquely robust in the case of signals with very low signal-to-noise ratios. Chirp coding for authenticating data is generic in the sense that it can be used for a range of data types and applications (the authentication of speech and audio signals, for example). The theoretical and computational aspects of the matched filter and the properties of a chirp ...


Mitigation Of Control Channel Jamming Under Node Capture Attacks, Patrick Tague, Mingyan Li, Radha Poovendran Aug 2009

Mitigation Of Control Channel Jamming Under Node Capture Attacks, Patrick Tague, Mingyan Li, Radha Poovendran

Patrick Tague

Availability of service in many wireless networks depends on the ability for network users to establish and maintain communication channels using control messages from base stations and other users. An adversary with knowledge of the underlying communication protocol can mount an efficient denial of service attack by jamming the communication channels used to exchange control messages. The use of spread spectrum techniques can deter an external adversary from such control channel jamming attacks. However, malicious colluding insiders or an adversary who captures or compromises system users are not deterred by spread spectrum, as they know the required spreading sequences. For ...


A Trade-Off Analysis Of Energy Detectors And Partitioned Search For Primary Detection, Robert H. Morelos-Zaragoza, Birsen Sirkeci, Vishal Sawant Aug 2009

A Trade-Off Analysis Of Energy Detectors And Partitioned Search For Primary Detection, Robert H. Morelos-Zaragoza, Birsen Sirkeci, Vishal Sawant

Robert Henry Morelos-Zaragoza

Cognitive radios aim to coexist in the unused spectrum bands which are licensed to primary users without harming the primary transmission/reception. For a cognitive radio, it is important to detect the band in which the primary is operating as fast as possible and with high reliability in order to adapt its transmission. In this work, we propose P-partitioning method in combination with energy detectors for the search of the band that the primary user is operating.


100 Ways You Can Use Google (Besides Searching), Marziah Karch Jul 2009

100 Ways You Can Use Google (Besides Searching), Marziah Karch

SIDLIT Conference Proceedings

Google has dozens of tools for educators and students. Learn how to make forms that feed into spreadsheets, blogs, social networks, websites, collaborative documents, videos, and more. During economic downturns it's more important than ever to make sure you and your students are utilizing free tools for collaborative learning and communication.


Twitter, Tumblr, Yammer, Huh? - How To Navigate Massive Information Streams And Have A Life, Marziah Karch Jul 2009

Twitter, Tumblr, Yammer, Huh? - How To Navigate Massive Information Streams And Have A Life, Marziah Karch

SIDLIT Conference Proceedings

Twitter has been getting a lot of attention lately, but it's not the only emerging application out there. In fact, by the time this presentation rolls around, there may already be something else making headlines. Learn why these new tools can help you as educators, lean how to use them, and learn how to navigate the tools without drowning in a sea of information and ending up with no life.


Failure Detectors For Wireless Sensor-Actuator Systems, Hamza A. Zia, Nigamanth Sridhar, Shivakumar Sastry Jul 2009

Failure Detectors For Wireless Sensor-Actuator Systems, Hamza A. Zia, Nigamanth Sridhar, Shivakumar Sastry

Electrical Engineering & Computer Science Faculty Publications

Wireless sensor-actuator systems (WSAS) offer exciting opportunities for emerging applications by facilitating fine-grained monitoring and control, and dense instrumentation. The large scale of such systems increases the need for such systems to tolerate and cope with failures, in a localized and decentralized manner. We present abstractions for detecting node failures and link failures caused by topology changes in a WSAS. These abstractions were designed and implemented as a set of reusable components in nesC under TinyOS. Results, which demonstrate the performance and viability of the abstractions, based on experiments on an 80 node testbed are presented. In the future ...


Modeling The Dynamics Of Network Technology Adoption And The Role Of Converters, Soumya Sen, Youngmi Jin, Roch Guérin, Kartik Hosanagar Jun 2009

Modeling The Dynamics Of Network Technology Adoption And The Role Of Converters, Soumya Sen, Youngmi Jin, Roch Guérin, Kartik Hosanagar

Departmental Papers (ESE)

New network technologies constantly seek to displace incumbents. Their success depends on technological superiority, the size of the incumbent's installed base, users' adoption behaviors, and various other factors. The goal of this paper is to develop an understanding of competition between network technologies, and identify the extent to which different factors, in particular converters (a.k.a. gateways), affect the outcome. Converters can help entrants overcome the influence of the incumbent's installed base by enabling cross-technology inter-operability. However, they have development, deployment, and operations costs, and can introduce performance degradations and functionality limitations, so that if, when, why ...


Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson Jun 2009

Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson

Computer Science Presentations

PDF of a powerpoint presentation from the 2009 ACM/IEEE Joint Conference on Digital Libraries, Austin, Texas, June 15-19, 2009. Also available on Slideshare.


General Direction Routing Protocol, Sean Michael Lydon Jun 2009

General Direction Routing Protocol, Sean Michael Lydon

Master's Theses and Project Reports

The General Direction Routing Protocol (GDRP) is a Wireless Sensor Network (WSN)

multi-path routing protocol which abstracts localization information (commonly GPS

coordinates) into relative direction information in order to perform routing decisions. By

generating relative direction information GDRP is able to operate with fewer precision

requirements than other protocols. This abstraction also allows the integration of other emerging

hardware-based localization techniques, for example, Beamforming Sensor Arrays.

GDRP does not specifically address the next hop a packet should take, but instead specifies a

direction it should travel. This direction abstraction allows for multiple paths to be taken through

the network thus ...


Internet-Scale Reactive Routing And Mobility, Daniel B. Nelson Jun 2009

Internet-Scale Reactive Routing And Mobility, Daniel B. Nelson

Master's Theses and Project Reports

Since its commercialization, the Internet has grown exponentially. A large variety of devices can communicate creating advanced services for a diverse ecosystem of applications. However, as the number of Internet hosts has grown, the size of routing tables required to correctly route data between them has also increased exponentially. This growth rate necessitates increasingly frequent upgrades to routing device hardware, providing them with additional memory for fast-access storage of route information. These upgrades are both physically and fiscally untenable, and a new Internet routing solution is necessary for future growth.

This research focuses around an incrementally deployable, reactive routing system ...