To achieve information superiority in a coalition environment the U. S. has to seamlessly integrate coalition members, both NATO and Non-NATO, into its command and control processes along all echelons of military operations. In a coalition environment, it is extremely challenging to fuse multinational information systems to achieve seamless integration. This thesis focuses on the security issues that are involved in establishing coalition network interoperability. The coalition environment is defined in terms of purpose, command structure, mission area, and control functions. Network and information protection are discussed in terms of minimizing the threats to information systems security. Coalition information system user requirements are defined and some of the security mechanisms required to meet those requirements are discussed. Current solutions to secure coalition network interoperability are surveyed, followed by conclusions, recommendations and areas for further study. / US Navy (USN) author

A thesis submitted to the Faculty of Engineering, University of the '\Vitwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy / THIS STUDY identifies and evaluates factors that affect call connections in the South African public data networks, modelling these factors to aid data network planning. The research shows the relationship between the economic rank of each region served and the data communication resources required for that region. Moreover, it shows the resources required between regions. THE THRUST of this thesis is that the volume of cans from a region can be estimated from its economic ...k and more than 75% olthe variation in the volume of calls between regions can be explained using the ranks of the originating and terminating regions. To prove this, records of more than four million calls are accumulated for all regions of the South African packet switched data network. An appropriate filtering and aggregation method is developed. EXISTING growth models including the gravity model are separately examined. Based on probability and dimensional arguments, the Bell System growth model is selected. It is revealed that the success of this model depends on one premise being satisfied: this model tacitly anti implicitly assumes that the originating and terminating calls are statistically independent. RETURNING to the data network, it is found that the call connections (after filtering and aggregation) display dependence of destination on origin. Reasons for the dependence are discovered. Multiple linear regression reveals the nature of this dependence. Surprisingly, distance is not a factor. The importance of regional ranks and an inter-regional indicator variable are also discovered. FINALL Y, call volume from a node is shown to be directly linked with the weighted Gross Regional and Industrial Product of the region. This quantity, in tum, is inversely related to the rank of the region. Call connections are then modelled to be equal to the call connections within the first tanked region divided by the product of the originating region's rank and the terminating region's rank. This simple and economical model explains 76% of the variations that occur in call connections. It has proved its use by being included in the data transfer services product-line report. / Andrew Chakane 2018

Message brokers are the backbone of modern publish subscribe messaging systems. These brokers can degrade or fail for a variety of reasons. This research specifically looks at the detection, prediction and mitigation of bottlenecks in brokers. The message-oriented-middleware framework here uses either a cluster of brokers on a Local Area Network (LAN) or a federation of brokers on a Wide Area Network (WAN) to route messages, facilitate multicasting and ameliorate demand surges and geographically related faults. Sensors have been constructed to monitor brokers and controllers to run the bottleneck detection algorithms. An overlay manager controls broker and topic pairing. Each topic is assigned a primary and secondary broker. When a failure is predicted, the overlay manager routes messages from the failing broker by switching topics to its secondary broker(s). The application for bottleneck forecasting is to allow us to pre-empt a broker failure and hence reroute messages to other brokers to increase resilience and reliability. The key contributions of this research are an abstract model of message-oriented-middleware broker based on the Apache Qpid message broker coupled with the use of analytical autoregressive exogenous (ARX) models that describes the broker behaviour during bottleneck conditions. The Apache Qpid message broker is a message broker that implements the Advanced Message Queuing Protocol (AMQP) for publish-subscribe messaging. ARX models are autoregressive models where the output depends on the previous output as well as external stimuli. These components are integrated to produce a generalised technique for calibrating broker performance and detection of bottlenecks in the broker. This research show how models were initially constructed using a complete range of input data. As bottlenecks occur only when the broker is heavily loaded, input data during idle periods can cause corruption to the model fit. Models were constructed with segmented input data, with each segment covering the range of one peak period. The segmented input allows the modelling of the broker behaviour only when it is experiencing a bottleneck. The result of this is a much-improved fit of the predictive models. The work here is compared against previous work using Markov-chains for creating predictive models. The results of both approaches are compared and reported.

Abstract not available

The strain on modern electrical power systems has led to an ever-increasing utilization of new information and communication technologies (ICT) to improve their efficiency and reliability. Wide area monitoring and control (WAMC) systems offer many opportunities to improve the real-time situational awareness in the power system. These systems are essen-tially SCADA systems but with continuous streaming of measurement data from the power system. The quality of WAMC systems and the applications running on top of them are heavily, but not exclusively, dependent on the underlying non-functional quality of the ICT systems. From an ICT perspective, the real-time nature of WAMC systems makes them susceptible to variations in the quality of the supporting ICT systems. The non-functional qualities studied as part of this research are performance, interoperability and cyber security. To analyze the performance of WAMC ICT systems, WAMC applications were identified, and their requirements were elicited. Furthermore, simulation models capturing typical utility communication infrastructure architectures were implemented. The simulation studies were carried out to identify and characterize the latency in these systems and its impact on data quality in terms of the data loss. While performance is a major and desirable quality, other non-functional qualities such as interoperability and cyber security have a significant impact on the usefulness of the sys-tem. To analyze these non-functional qualities, an enterprise architecture (EA) based framework for the modeling and analysis of interoperability and cyber security, specialized for WAMC systems, is proposed. The framework also captures the impact of cyber security on the interoperability of WAMC systems. Finally, a prototype WAMC system was imple-mented to allow the validation of the proposed EA based framework. The prototype is based on existing and adopted open-source frameworks and libraries. The research described in this thesis makes several contributions. The work is a systematic approach for the analysis of the non-functional quality of WAMC ICT systems as a basis for establishing the suitability of ICT system architectures to support WAMC applications. This analysis is accomplished by first analyzing the impact of communication architectures for WAMC systems on the latency. Second, the impact of these latencies on the data quali-ty, specifically data currency (end to end delay of the phasor measurements) and data in-completeness (i.e., the percentage of phasor measurements lost in the communication), is analyzed. The research also provides a framework for interoperability and cyber security analysis based on a probabilistic Monte Carlo enterprise architecture method. Additionally, the framework captures the possible impact of cyber security on the interoperability of WAMC data flows. A final result of the research is a test bed where WAMC applications can be deployed and ICT architectures tested in a controlled but realistic environment. / <p>QC 20130218</p>

Persistics is an advanced framework for processing wide-area aerial surveillance video. This framework handles the tasks of data collection, stitching of multi-sensor imagery, image registration and stabilization, motion tracking, and compression. As the technology for image sensor sizes improves, significant improvements in compression techniques are necessary in order to make full use of the data. Because the information of interest in such video is naturally moving, point-like targets, the applicability of foveated coding to the compression problem is an interesting question. Foveated coding, a compression technique that was designed to be perceptually optimal for the human visual system, has several components that are appropriate to the persistics compression problem. Foveation is applied in several different scenarios and methods to persistics data. As foveation can make good use of the persistics tracker data, a problem affecting tracker performance is explored as well. The multi-sensor stitching component of persistics can generate artifacts that reduce the effectiveness of the tracker. A method for characterizing, detecting, and correcting such artifacts is desirable. These three concepts are explored, and a method for detection is developed. Components of these algorithms were absorbed into a more general framework for artifact correction. / text

The strain on modern electrical power system operation has led to an ever increasing utilization of new Information Communication Technology (ICT) systems to enhance the reliability and efficiency of grid operation. Among these proposals, Phasor Measurement Unit (PMU)-based Wide-Area Monitoring and Control (WAMC) systems have been recognized as one of the enablers of “Smart Grid”, particularly at the transmission level, due to their capability to improve the real-time situational awareness of the grid. These systems differ from the conventional Supervisory Control And Data Acquisition (SCADA) systems in that they provide globally synchronized measurements at high resolutions. On the other hand, the WAMC systems also impose several stringent requirements on the underlying ICT systems, including performance, security, and availability, etc. As a result, the functionality of the WAMC applications is heavily, but not exclusively, dependent on the capabilities of the underlying ICT systems. This tight coupling makes it difficult to fully exploit the benefits of the synchrophasor technology without the proper design and configuration of ICT systems to support the WAMC applications. The strain on modern electrical power system operation has led to an ever increasing utilization of new Information Communication Technology (ICT) systems to enhance the reliability and efficiency of grid operation. Among these proposals, Phasor Measurement Unit (PMU)-based Wide-Area Monitoring and Control (WAMC) systems have been recognized as one of the enablers of “Smart Grid”, particularly at the transmission level, due to their capability to improve the real-time situational awareness of the grid. These systems differ from the conventional Supervisory Control And Data Acquisition (SCADA) systems in that they provide globally synchronized measurements at high resolutions. On the other hand, the WAMC systems also impose several stringent requirements on the underlying ICT systems, including performance, security, and availability, etc. As a result, the functionality of the WAMC applications is heavily, but not exclusively, dependent on the capabilities of the underlying ICT systems. This tight coupling makes it difficult to fully exploit the benefits of the synchrophasor technology without the proper design and configuration of ICT systems to support the WAMC applications. In response to the above challenges, this thesis addresses the dependence of WAMC applications on the underlying ICT systems. Specifically, two of the WAMC system data quality attributes, latency and completeness, are examined together with their effects on a typical WAMC application, PMU-based wide-area damping systems. The outcomes of this research include quantified results in the form of PMU communication delays and data frame losses, and probability distributions that can model the PMU communication delays. Moreover, design requirements are determined for the wide-area damping systems, and three different delay-robust designs for this WAMC application are validated based on the above results. Finally, a virtual PMU is developed to perform power system and communication network co-simulations. The results reported by this thesis offer a prospect for better predictions of the performance of the supporting ICT systems in terms of PMU data latency and completeness. These results can be further used to design and optimize the WAMC applications and their underlying ICT systems in an integrated manner. This thesis also contributes a systematic approach to design the wide-area damping system considering the PMU data latency and completeness. Finally, the developed virtual PMU, as part of a co-simulation platform, provides a means to investigate the dependence of WAMC applications on the capabilities of the underlying ICT systems in a cost-efficient manner. / <p>QC 20131015</p>

The dissertation addresses the communication issues of interconnecting the different government sectors LANs, and access to the global Internet. Network capacities are being purposely overengineered in today's commercial Internet. Any network provider, be it a commercial Internet Service Provider (ISP) or Information Technology Service department at government sector, company or university site, will design network bandwidth resources in such a way that there will be virtually no data loss, even during the worst possible network utilization scenario. Thus, the service delivered by today's end-to-end wide area Internet would be perfect if it wasn't for the inter-domain connections, such as Internet access link to the ISP, or peering points between ISPs. The thesis studies the performance of the network in Eritrea, displaying the problems of Local Area Networks (LANs) and Wide Area Networks (WAN) and suggesting initial solutions and investigating the performance of (WAN) through the measured traffic analysis between Asmara LAN and Massawa LAN, using queuing theory system (M/M/1 and M/M/2) solution. The dissertation also uses OPNET IT Guru simulation software program ·to study the performance of LAN and WLAN in Eritrea. The items studied include traffic, collision, packet loss, and queue delay. Finally in order to follow the current trends, we study the performance ofVOIP links in Eritrean WANs environment, with a focus on five different link capacities: 28 kbps, 33 kbps, 64 kbps, and 128 kbps for voice and 256/512 kbps for voice and data. Using the R value as a measure of mean opinion score (MOS), we determine that the 33 kbps link would be adequate for Eritrean WANs. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2006.

Object appearance models are a consequence of illumination, viewing direction, camera intrinsics, and other conditions that are specific to a particular camera. As a result, a model acquired in one view is often inappropriate for use in other viewpoints. In this work we treat this appearance model distortion between two non-overlapping cameras as one in which some unknown color transfer function warps a known appearance model from one view to another. We demonstrate how to recover this function in the case where the distortion function is approximated as general affine and object appearance is represented as a mixture of Gaussians. Appearance models are brought into correspondence by searching for a bijection function that best minimizes an entropic metric for model dissimilarity. These correspondences lead to a solution for the transfer function that brings the parameters of the models into alignment in the UV chromaticity plane. Finally, a set of these transfer functions acquired from a collection of object pairs are generalized to a single camera-pair-specific transfer function via robust fitting. We demonstrate the method in the context of a video surveillance network and show that recognition of subjects in disjoint views can be significantly improved using the new color transfer approach.

The presence of inter-area oscillations has long affected stability constraints, and therefore, limited the power transfer capacity of interconnected power systems. Adequate damping of these inter-area oscillations is, thus, necessary to secure system operation and ensure system reliability while increasing power transfers. Power system stabilizers (PSS) are the most common devices used to enhance the damping of such oscillations. Many studies have demonstrated that PSSs using remote signals may perform better than using local signals. The advent of phasor measurement units (PMU) makes remote or wide-area signals become available, which enables various important applications. Of particular interest is wide-area damping control (WADC), which aims to utilize remote or wide-area measurements to damp the inter-area oscillations. However, two main challenges in WADC design are (1) feedback controller input signal selection (which PMU signal is best to use?), and (2) latency (which is inherent in the transmission of the measurements) considerations. In response to the first challenge, this thesis proposes a concept called dominant inter-area oscillation path, which serves to pinpoint a set of candidate signals that can be used as the feedback controller inputs by locating the interconnected corridors where the inter-area modal contents are the most observable. Derivation, identification, and use of the dominant inter-area oscillation paths are demonstrated throughout the thesis. Extensive analysis on the relationships between the proposed set of signals and system properties regarding stability and robustness is presented. To tackle the second challenge, the impacts of time delays on the system performance when using the dominant path signals are investigated. To date, several studies have proposed different control design methods using various oscillation dampers to design WADC. Nevertheless, neither a systematic method nor a concept that encompasses fundamental knowledge on power system dynamics has yet been offered. The objective of this thesis is, thus, to propose an analytical framework based on the dominant path concept which is built upon fundamental principles for feedback controller input signal selection in WADC. With this framework, a proper and systematic approach is developed. The proposed method allows to select appropriate signals and use them to effectively mitigate the inter-area oscillations that constrain power transfer capacity and affect system stability. / <p>QC 20150414</p>