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The application of distributed virtual machines for enterprise computer management: A two-tier network file system for image provisioning and management

Aguiar, César S.; Cruz, Daniel I.; Ulson, Roberta S.; Cavenaghi, Marcos A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 428-431
Português
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46.05%
In order to simplify computer management, several system administrators are adopting advanced techniques to manage software configuration of enterprise computer networks, but the tight coupling between hardware and software makes every PC an individual managed entity, lowering the scalability and increasing the costs to manage hundreds or thousands of PCs. Virtualization is an established technology, however its use is been more focused on server consolidation and virtual desktop infrastructure, not for managing distributed computers over a network. This paper discusses the feasibility of the Distributed Virtual Machine Environment, a new approach for enterprise computer management that combines virtualization and distributed system architecture as the basis of the management architecture. © 2008 IEEE.

Changing Community Health Behaviors with a Health Promotion Computer Network: Preliminary Findings from Stanford Health-Net

Robinson, Thomas N.; Walters, Paul A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 04/11/1987 Português
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Computer-based health education has been employed in many settings. However, data on resultant behavior change are lacking. A randomized, controlled, prospective study was performed to test the efficacy of Stanford Health-Net in changing community health behaviors. Graduate and undergraduate students (N=1003) were randomly assigned to treatment and control conditions. The treatment group received access to Health-Net, a health promotion computer network emphasizing specific self-care and preventive strategies. Over a four month intervention period, 26% of the treatment group used Health-Net an average of 6.4 times each (range 1 to 97). Users rated Health-Net favorably. The mean number of ambulatory medical visits decreesed 22.5% more in the treatment group than in the control group (P<.05), while hospitalizations did not differ significantly between groups. In addition, perceived self-efficacy for preventing the acquisition of a STD and herpes increased 577% (P<.05) and 261% (P<.01) more, respectively, in the treatment group than in the control group. These findings suggest that access to Stanford Health-Net can result in significant health behavior change. The advantages of the network approach make it a potential model for other communities.

Localization and sensing applications in the Pushpin Computer Network

Broxton, Michael Joseph
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 124 p.; 7439785 bytes; 7446044 bytes; application/pdf; application/pdf
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The utility and purpose of a node in a wireless sensor network is intimately tied to the physical space in which it is distributed. As such, it is advantageous under most circumstances for a sensor node to know its position. In this work, we present two systems for localizing a network of roughly 60 sensor nodes distributed over an area of 1-m2. One is based on a linear lateration technique, while the second approach utilizes non-linear optimization techniques, namely spectral graph drawing and mesh relaxation. In both cases, localization is accomplished by generating distance constraints based on ultrasound time-of-flight measurements to distinct, global sensor stimuli. These distance constraints alone are sufficient to achieve localization; no a priori knowledge of sensor node coordinates or the coordinates of the global sensor events are required. Using this technique, we have achieved a localization error of 2.30-cm and an error standard deviation of 2.36-cm.; by Michael Joseph Broxton.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.; Includes bibliographical references (p. 117-124).

Proactive mobile wireless networks : an infrastructureless wireless network architecture for delay-sensitive applications; Infrastructureless wireless network architecture for delay-sensitive applications

Dai, Lillian Lei, 1978-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 213 p.
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Infrastructureless wireless networks are an important class of wireless networks that is best suited for scenarios where there is temporary and localized telecommunication demand. Such networks consist of wireless devices that can form a network autonomously without the need for pre-deployed telecommunication infrastructures such as base-stations and access points. Over the past several decades, significant research and development efforts have been devoted to a particular type of infrastructureless wireless networks called mobile ad hoc wireless networks (MANETs). In addition to autonomous network formation, wireless devices in MANETs have routing capabilities and help one another to forward information in a multihop fashion. The applications envisioned for MANETs include communication during disaster relief, search and rescue, and small tactical unit operations where the existing telecommunication infrastructures may be destroyed or are unavailable. While significant strides have been made in all aspects of MANET networking, adoption of such technology has been limited to date despite its potential. We believe that this lack of adoption is due to a fundamental mismatch between application demands and the MANET network architecture. While the flexibility of anytime and anywhere communication offered by MANETs is appealing...

An Epistemic Event-based Correlation Scheme for Pervasive Network Management

Ganapathy, Vinayak
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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Computer networks produce tremendous amounts of event-based data that can be collected and managed to support an increasing number of new classes of pervasive applications. Examples of such applications are network monitoring and crisis management. Although the problem of distributed event-based management has been addressed in the non-pervasive settings such as the Internet, the domain of pervasive networks has its own characteristics that make these results non-applicable. Many of these applications are based on time-series data that possess the form of time-ordered series of events. Such applications also embody the need to handle large volumes of unexpected events, often modified on-the-fly, containing conflicting information, and dealing with rapidly changing contexts while producing results with low-latency. Correlating events across contextual dimensions holds the key to expanding the capabilities and improving the performance of these applications. This dissertation addresses this critical challenge. It establishes an effective scheme for complex-event semantic correlation. The scheme examines epistemic uncertainty in computer networks by fusing event synchronization concepts with belief theory. Because of the distributed nature of the event detection...

Hacking social networks examining the viability of using computer network attack against social networks

Schuhart, Russell G.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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Social Network Analysis (SNA) has been proposed as a tool to defeat transnational terrorist groups such as Al Qaeda. However, SNA is an descriptive tool that is a product of sociology and not an offensive tool used to attack a social network. SNA was not designed to destabilize covert networks that are difficult to observe and penetrate. This work presents a possible way to improve SNAâ s performance against a covert social network by employing the Computer Network Attack (CNA) model. The CNA model is used by computer network security to represent the traditional approach to hacking a computer network. Although not tested in this paper, it is argued that the CNA model should be able to improve the accuracy of SNA when applied to a covert social network by standardizing the destabilization process and allowing for frequent challenges of operating assumptions. A history and overview of both computer networks and social networks is covered to allow for a comparison of the two networks. The networks have enough similarities to allow the application of the CNA model without major modification from its original form. Assumptions about the security of computer and social networks are examined to clarify how the CNA model can attack a social network. The model is examined for validity and the conclusion is that the CNA model can incorporate SNA into a more methodical approach to achieve better results that using SNA alone. The final portion of the paper details a possible implementation of the CNA model and how it can be used as part of an offensive effort to destabilize a covert social network.

Building a simulation toolkit for wireless mesh clusters and evaluating the suitability of different families of ad hoc protocols for the Tactical Network Topology

Karapetsas, Konstantinos
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xx, 77 p. : ill.
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Approved for public release, distribution is unlimited; Wireless mesh networking has emerged as the successor of the traditional ad hoc networks. New technological advances, the standardization of protocols and interfaces and the maturity of key components have made it possible for current mesh research groups to set goals that are really close to the world's expectations. The objective of this research is to design and implement a simulation toolkit for wireless mesh clusters that can be used as an additional performance evaluation technique for the Tactical Network Topology program of Naval Postgraduate School. This toolkit is implemented in the OPNET simulation environment and it incorporates various nodes running different ad hoc routing protocols. Furthermore, the investigation of a suitable combination of protocols for the Tactical Network Topology is achieved by creating scenarios and running a number of simulations using the mesh toolkit.; Captain, Hellenic Air Force

A legal reasoning component of a network security command and control system

Sousa, Goncalo.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 79 p. : ill. ;
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Approved for public release; distribution is unlimited; There are numerous computer-aided tools to enable Computer Network Defense. However, their effectiveness in countering attacks is less than optimal when they are used independently of one another. Research has identified the requirements for an integrated command and control (C2) system that is able to conduct full-spectrum operations in the cyberspace environment. The most notable of that research revolves around the development and experimentation with the prototype system known as Cyber Command, Control and Information Operations System (C3IOS). C3IOS provides for a loose confederation of the cooperating systems with interaction between systems going through C2 interfaces. In this thesis, the authors introduce into C3IOS a means to support the commander's ability to take measured responses to coercive actions in a timely manner, specifically to facilitate the interaction between experts in the law of information conflict and information warriors responding to a cyber attack. The authors' research results in a set of use cases and requirements for the C2 understanding, planning, and deciding activities involved in such a capability, using Schmitt's analysis as an example.; Portuguese Navy author

Desirable properties of a network taxonomy

McCoy, Earl E.; Carey, Bernard J.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Relatório Formato: 39 p. : ill. ; 28 cm.
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This paper reviews and analyzes the desirable properties of a computer network taxonomy from the point of view of its usefulness in a design procedure. A key factor that must be considered is that the design environment currently evolving uses functionally high level VLSI-based building blocks to construct various network architectures. This paper begins by reviewing the uses of a taxonomy in a network context, and continues with a review of specifications for network requirements. A set of hardware interconnection primitives is defined next. A review of the Anderson and Jensen taxonomy (Ander75) is then presented, with a discussion of its completeness. The main thrust of this article is given in a section of attributes of a design oriented taxonomy. Finally, extensions are proposed for fault tolerant considerations and protocols. A computer network is defined to be a hetrogeneous collection of computers and the telecommunications subsystem linking them together. Here the properties of the various network architectures are of particular interest; the 'user' computers (or processors) are considered as sources and sinks of messages being transmitted over the network. No distinction as to the geographical scope of the network is made because it does not impact the taxonomy considerations addressed here. (Author); supported by the Department of Computer Science...

Network security and the NPS Internet firewall; NA

Schively, Jody L.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 105 p.;28 cm.
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As the Naval Postgraduate School's (NPS) computer network continues to incorporate computers with a wide variety of security holes, it is vital that an Internet firewall be installed to provide perimeter security for NPS from the Internet. NPS has had systems compromised by unauthorized individuals who have gained access via the Internet. The approach taken by this thesis was to analyze the type of Internet firewalls available and chose a design that provides the protection required at NPS while maintaining the Internet functionality desired. After choosing the appropriate type of firewall, it was tested for functionality and performance. The functionality test successfully validated that the bootp, netwall, tftp, sunrpc, and nfsd packets could he blocked while other network services remained functional. The performance testing process first monitored existing traffic to and from the BARRNET and DDN routers. The second step determined the firewall's performance with a well known network measurement tool, New Test TCP/IP (ntrcp). The existing data rates to and from the Intemet are on average 438 kilobjis per second and the nttcp tests showed that the firewall could run at 600 kilobits per second. These results validated that the firewall could maintain the data rates currently required to the Internet. This thesis resulted in a firewall...

Network policy languages: a survey and a new approach

Stone, Gary; Lundy, Bert; Xie, Geoffrey
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Relatório Formato: x, 37 p.;28 cm.
Português
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Approved for public release, distribution is unlimited; In this report a survey of current network policy languages is presented. Next, a summary of the techniques for detecting policy conflicts is given. Finally, a new language, Path-based Policy Language (PPL), which offers improvements to these is introduced. Previous network policy languages vary from the very specific, using packet filters at the bit level, to the more abstract where concepts are represented, with implementation details left up to individual network devices. As background information a policy framework model and policy- based routing protocols are discussed. PPL's path-based approach for representing network policies is advantageous in that Quality of Service (QoS) and security policies can be associated with an explicit path through the network. This assignment of policies to network flows aids in new initiatives such as Integrated Services. The more stringent requirement of supporting path- based policies can be easily relaxed with the use of wild card characters to also support Differentiated Services and best-effort service, which is provided by the Internet today.

Architectures for device aware network

Chung, Wai Kong.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 83 p. : ill. (some col.) ;
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In today's heterogeneous computing environment, a wide variety of computing devices with varying capabilities need to access information in the network. Existing network is not able to differentiate the different device capabilities, and indiscriminatingly send information to the end-devices, without regard to the ability of the end-devices to use the information. The goal of a device-aware network is to match the capability of the end-devices to the information delivered, thereby optimizing the network resource usage. In the battlefield, all resources - including time, network bandwidth and battery capacity - are very limited. A device-aware network avoids the waste that happens in current, device-ignorant networks. By eliminating unusable traffic, a device-aware network reduces the time the end-devices spend receiving extraneous information, and thus saves time and conserves battery-life. In this thesis, we evaluated two potential DAN architectures, Proxy-based and Router-based approaches, based on the key requirements we identified. To demonstrate the viability of DAN, we built a prototype using a hybrid of the two architectures. The key elements of our prototype include a DAN browser, a DAN Lookup Server and DAN Processing Unit (DPU). We have demonstrated how our architecture can enhance the overall network utility by ensuring that only appropriate content is delivered to the end-devices.

Developing a reliable methodology for assessing the computer network operations threat of North Korea

Brown, Christopher
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xiv, 77 p. : ill. (some col.) ;
Português
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Approved for release; distribution is unlimited; Computer network operations (CNO) can be considered a relatively new phenomenon being encount modern warfare. Computer network operation is comprised of three components, computer network attack computer network exploitation (CNE), and computer network defense (CND). Computer network attack is def operations to disrupt, deny, degrade, or destroy information resident in computer networks, or the computers and ne themselves. Computer network exploitation is the intelligence collection and enabling operations to gather data from adversary automated information systems (AIS) or networks. Finally, computer network defense are those me internal to the protected entity, taken to protect and defend information, computers, and networks from disruption, degradation, or destruction. No longer is warfare limited to the use of kinetic weapons and conventional methods of war. Computer network operations have become an integral part of our adversary's arsenal and more attention must be paid to the effects of CNO activities, particularly CNA and CNE being conducted by our adversaries. Of the many states suspected of conducting active CNO activities against the United States and other nations, none warrants more attention than North Korea. This thesis presents the development of methodology using information available from open sources. This work is intended to prove that a useful methodology for assessing the CNO capabilities and limitations of North Korea can be developed using only open source information.; Lieutenant...

FireViz : a personal firewall visualizing tool; FireViz : a personal network firewall visualizing tool

Sharma, Nidhi
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 95 p.; 4618721 bytes; 4622665 bytes; application/pdf; application/pdf
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In this thesis, I present FireViz, a personal firewall visualizing tool. FireViz visually displays activities of a personal firewall in real time. The primary goal of FireViz is to educate typical computer users of the security threats their computers are exposed to when connected to a network and expose any potential loop holes in the firewall's security policies. To this end, FireViz presents a novel visualization paradigm that provides users with an informative yet non-intrusive interface to their network and firewall. FireViz achieves this by incorporating a peripheral mapping of the network on the user's screen and displaying network events along this periphery. Information about network events is encoded visually to help users develop a more intuitive model of the network at a low cost. The peripheral nature of FireViz along with the use of non-modal visual displays allows users to easily understand network events without obstructing their primary tasks. The visualization is also capable of highlighting exceptional events that may represent potential threats without relying on the end user to understand ally threat model. Thus, FireViz aims to provide users with a superior framework for understanding the network security model and achieving improved system security in the process.; by Nidhi Sharma.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

Dynamic file allocation in a computer network

Fonte: Electronic Systems Laboratory, Dept. of Electrical Engineering and Computer Science, Massachusetts Institute of Technology Publicador: Electronic Systems Laboratory, Dept. of Electrical Engineering and Computer Science, Massachusetts Institute of Technology
Formato: 176 p.; application/pdf
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by Francisco de As?Ros Per?; Bibliography: p.175-176.; Prepared under Advanced Research Project Agency Contract N00014-75-C-1183. Originally presented as the author's thesis, (M.S.) in the M.I.T. Dept. of Electrical Engineering and Computer Science, 1976.

Global Modeling and Prediction of Computer Network Traffic

Stoev, Stilian A.; Michailidis, George; Vaughan, Joel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/05/2010 Português
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55.96%
We develop a probabilistic framework for global modeling of the traffic over a computer network. This model integrates existing single-link (-flow) traffic models with the routing over the network to capture the global traffic behavior. It arises from a limit approximation of the traffic fluctuations as the time--scale and the number of users sharing the network grow. The resulting probability model is comprised of a Gaussian and/or a stable, infinite variance components. They can be succinctly described and handled by certain 'space-time' random fields. The model is validated against simulated and real data. It is then applied to predict traffic fluctuations over unobserved links from a limited set of observed links. Further, applications to anomaly detection and network management are briefly discussed.

A Tutorial on Network Security: Attacks and Controls

Meghanathan, Natarajan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/12/2014 Português
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With the phenomenal growth in the Internet, network security has become an integral part of computer and information security. In order to come up with measures that make networks more secure, it is important to learn about the vulnerabilities that could exist in a computer network and then have an understanding of the typical attacks that have been carried out in such networks. The first half of this paper will expose the readers to the classical network attacks that have exploited the typical vulnerabilities of computer networks in the past and solutions that have been adopted since then to prevent or reduce the chances of some of these attacks. The second half of the paper will expose the readers to the different network security controls including the network architecture, protocols, standards and software/ hardware tools that have been adopted in modern day computer networks.; Comment: 21 pages, 19 figures

Computer Network Topology Design in Limelight of Pascal Graph Property

Pal, Sanjay Kumar; Sarma, Samar Sen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/03/2010 Português
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Constantly growing demands of high productivity and security of computer systems and computer networks call the interest of specialists in the environment of construction of optimum topologies of computer mediums. In earliest phases of design, the study of the topological influence of the processes that happen in computer systems and computer networks allows to obtain useful information which possesses a significant value in the subsequent design. It has always been tried to represent the different computer network topologies using appropriate graph models. Graphs have huge contributions towards the performance improvement factor of a network. Some major contributors are de-Bruijn, Hypercube, Mesh and Pascal. They had been studied a lot and different new features were always a part of research outcome. As per the definition of interconnection network it is equivalent that a suitable graph can represent the physical and logical layout very efficiently. In this present study Pascal graph is researched again and a new characteristics has been discovered. From the perspective of network topologies Pascal graph and its properties were first studied more than two decades back. Since then, a numerous graph models have emerged with potentials to be used as network topologies. This new property is guaranteed to make an everlasting mark towards the reliability of this graph to be used as a substantial contributor as a computer network topology. This shows its credentials over so many other topologies. This study reviews the characteristics of the Pascal graph and the new property is established using appropriate algorithm and the results.; Comment: 6 Pages...

Simulation of Computer Network Attacks

Sarraute, Carlos; Miranda, Fernando; Orlicki, Jose I.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/06/2010 Português
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55.93%
In this work we present a prototype for simulating computer network attacks. Our objective is to simulate large networks (thousands of hosts, with applications and vulnerabilities) while remaining realistic from the attacker's point of view. The foundation for the simulator is a model of computer intrusions, based on the analysis of real world attacks. In particular we show how to interpret vulnerabilities and exploits as communication channels. This conceptual model gives a tool to describe the theater of operations, targets, actions and assets involved in multistep network attacks. We conclude with applications of the attack simulator.; Comment: 17 pages, 3 figures. Argentine Symposium on Computing Technology (AST) 2007 - 36 JAIIO

The status and use of computer network attacks in international humanitarian law.

Dinniss, Heather Harrison
Fonte: London School of Economics and Political Science Thesis Publicador: London School of Economics and Political Science Thesis
Tipo: Thesis; NonPeerReviewed Formato: application/pdf
Publicado em //2008 Português
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The information revolution has transformed both modern societies and the way in which they conduct warfare. This thesis analyses the status of computer network attacks in international law and examines their treatment under the laws of armed conflict. A computer network attack is any operation designed to disrupt, deny, degrade or destroy information resident in computers and computer networks, or the computers and networks themselves. The first part of the thesis deals with a States right to resort to force and uses the U.N. Charter system to analyse whether and at what point a computer network attack will amount to a use of force or an armed attack, and examines the permitted responses against such an attack. The second part of the thesis addresses the applicability of international humanitarian law to computer network attacks by determining under what circumstances these attacks will constitute an armed conflict. It concludes that the jus in bello will apply where the perceived intention of the attacking party is to cause deliberate harm and the foreseeable consequence of the acts includes injury, death damage or destruction. In examining the regulation of these attacks under the Jus in bello the author addresses the legal issues associated with this method of attack in terms of the current law and examines the underlying debates which are shaping the modern laws applicable in armed conflict. Participants in conflicts are examined as increased civilianisation of the armed forces is moving in lock-step with advances in technology. Computer network attacks also present new issues for the law relating to targeting and precautions in attack which are addressed; objects subject to special protections...