Modelling, Dimensioning and Optimization of 5G Communication Networks, Resources and Services

This reprint aims to collect state-of-the-art research contributions that address challenges in the emerging 5G networks design, dimensioning and optimization. Designing, dimensioning and optimization of communication networks resources and services have been an inseparable part of telecom network development. The latter must convey a large volume of traffic, providing service to traffic streams with highly differentiated requirements in terms of bit-rate and service time, required quality of service and quality of experience parameters. Such a communication infrastructure presents many important challenges, such as the study of necessary multi-layer cooperation, new protocols, performance evaluation of different network parts, low layer network design, network management and security issues, and new technologies in general, which will be discussed in this book

A methodology for obtaining More Realistic Cross-Layer QoS Measurements in mobile networks: A VoIP over LTE Use Case

Los servicios de voz han sido durante mucho tiempo la primera fuente de ingresos para los operadores móviles. Incluso con el protagonismo creciente del tráfico de datos, los servicios de voz seguirán jugando un papel importante y no desaparecerán con la transición a redes basadas en el protocolo IP. Por otra parte, hace años que los principales actores en la industria móvil detectaron claramente que los usuarios no aceptarían una degradación en la calidad de los servicios de voz. Es por esto que resulta crítico garantizar la experiencia de usuario (QoE) en la transición a redes de nueva generación basadas en conmutación de paquetes. El trabajo realizado durante esta tesis ha buscado analizar el comportamiento y las dependencias de los diferentes servicios de Voz sobre IP (VoIP), así como identificar configuraciones óptimas, mejoras potenciales y metodologías que permitan asegurar niveles de calidad aceptables al mismo tiempo que se trate de minimizar los costes. La caracterización del rendimiento del tráfico de datos en redes móviles desde el punto de vista de los usuarios finales es un proceso costoso que implica la monitorización y análisis de un amplio rango de protocolos y parámetros con complejas dependencias. Para abordar desde la raíz este problema, se requiere realizar medidas que relacionen y correlen el comportamiento de las diferentes capas. La metodología de caracterización propuesta en esta tesis proporciona la posibilidad de recoger información clave para la resolución de problemas en las comunicaciones IP, relaciolándola con efectos asociados a la propagación radio, como cambios de celda o pérdida de enlaces, o con carga de la red y limitaciones de recursos en zonas geográficas específicas. Dicha metodología se sustenta en la utilización de herramientas nativas de monitorización y registro de información en smartphones, y la aplicación de cadenas de herramientas para la experimentación extensiva tanto en redes reales y como en entornos de prueba controlados. Con los resultados proporcionados por esta serie de herramientas, tanto operadores móviles y proveedores de servicio como desarrolladores móviles podrían ganar acceso a información sobre la experiencia real del usuario y sobre cómo mejorar la cobertura, optimizar los servicios y adaptar el funcionamiento de las aplicaciones y el uso de protocolos móviles basados en IP en este contexto. Las principales contribuciones de las herramientas y métodos introducidos en esta tesis son los siguientes: - Una herramienta de monitorización multicapa para smartphones Android, llamada TestelDroid, que permite la captura de indicadores clave de rendimiento desde el propio equipo de usuario. Asimismo proporciona la capacidad de generar tráfico de forma activa y de verificar el estado de alcanzabilidad del terminal, realizando pruebas de conectividad. - Una metodología de post-procesado para correlar la información presente en las diferentes capas de las medidas realizadas. De igual forma, se proporciona la opción a los usuarios de acceder directamente a la información sobre el tráfico IP y las medidas radio y de aplicar metodologías propias para la obtención de métricas. - Se ha realizado la aplicación de la metodología y de las herramientas usando como caso de uso el estudio y evaluación del rendimiento de las comunicaciones basadas en IP a bordo de trenes de alta velocidad. - Se ha contribuido a la creación de un entorno de prueba realista y altamente configurable para la realización de experimentos avanzados sobre LTE. - Se han detectado posibles sinergias en la utilización de instrumentación avanzada de I+D en el campo de las comunicaciones móviles, tanto para la enseñanza como para la investigación en un entorno universitario

Proposta 3GPP de indicadores de desempenho de rede - R4 CS Core Network

Mestrado em Engenharia Electrónica e TelecomunicaçõesO mercado de telecomunicações tem vindo a tornar-se cada vez mais competitivo e agressivo devido à diminuição das margens dos operadores de telecomunicações. Este facto é igualmente relevante no mercado das redes móveis em que este trabalho se foca. A maior parte dos actuais mercados de redes móveis pauta-se por uma consolidação da sua base instalada e por uma optimização dos recursos existentes. Por uma questão de estratégia comercial e técnica (não dependência de um único fornecedor) é frequente os operadores de redes móveis terem mais do que um fornecedor de equipamentos de telecomunicações para a sua rede. Devido a este facto, os problemas das redes com multi-fabricantes agudizou-se o que levou à premente necessidade de se arranjar uma linguagem comum através da qual se consiga ter uma ideia do nível global de desempenho alcançado e dos pontos críticos em que a rede pode melhorar o seu desempenho. É nesta problemática que o presente trabalho se foca. Neste momento, o 3GPP tem definidos uma quantidade vasta de indicadores de desempenho de rede para a área Circuit Switch (CS) Core Network (CN) mas ainda não tem definidos os seus Key Performance Indicators (KPIs). Tendo como base os indicadores de desempenho 3GPP existentes, esta Dissertação propõe um conjunto de KPIs que possibilitam a análise do desempenho da rede Core Network ao nível da sua parte CS. Esta Dissertação apresenta as propostas de KPIs para a rede CS, as quais estão divididas em três partes. Numa primeira parte são apresentados os KPIs relativos ao MSC Server (MSS) ao nível da análise de acessibilidade, utilização e mobilidade. Na segunda secção são apresentados os KPIs relativos ao Media Gateway (MGW) ao nível da análise de acessibilidade, integridade e utilização. Finalmente na terceira e última secção apresentam-se os KPIs associados ao HLR.The telecommunications market has become increasingly competitive and aggressive due to the decreasing margins of telecom operators. This fact is also relevant in the mobile networks market in which this Thesis is focused. Most of today's mobile networks is guided by a consolidation of its installed base and by optimizing existing resources. As a matter of business strategy and technique (not dependent on one supplier) it is common for the mobile network operators to have more than one telecommunications equipment supplier. Due to this, the problems of multi-vendor networks has worsened leading to the urgent need to find a common language that everyone speaks and, through which, can get an idea of overall performance level achieved and critical points where the network can improve its performance. This paper is focused on this issue. Currently, 3GPP has defined a wide range of network performance indicators for the Core Network (CN) Circuit Switch (CS) area but, nothing is yet set in what Key Performance Indicators (KPIs) is concerned. The purpose of this Thesis is, based on already existent 3GPP performance indicators, recommend a set of KPIs to enable the CS CN performance analysis. This Thesis present the CS KPI proposals which are divided in three main parts. In the first part, are presented the MSC Server (MSS) KPIs at accessibility analysis, usage and mobility levels. In the second part are presented the Media Gateway (MGW) related KPIs at accessibility analysis, integrity and usage levels. Finally we have the third and last part where the HLR related KPIs are presented

Improving Access and Mental Health for Youth Through Virtual Models of Care

The overall objective of this research is to evaluate the use of a mobile health smartphone application (app) to improve the mental health of youth between the ages of 14–25 years, with symptoms of anxiety/depression. This project includes 115 youth who are accessing outpatient mental health services at one of three hospitals and two community agencies. The youth and care providers are using eHealth technology to enhance care. The technology uses mobile questionnaires to help promote self-assessment and track changes to support the plan of care. The technology also allows secure virtual treatment visits that youth can participate in through mobile devices. This longitudinal study uses participatory action research with mixed methods. The majority of participants identified themselves as Caucasian (66.9%). Expectedly, the demographics revealed that Anxiety Disorders and Mood Disorders were highly prevalent within the sample (71.9% and 67.5% respectively). Findings from the qualitative summary established that both staff and youth found the software and platform beneficial

The Impact of Digital Technologies on Public Health in Developed and Developing Countries

This open access book constitutes the refereed proceedings of the 18th International Conference on String Processing and Information Retrieval, ICOST 2020, held in Hammamet, Tunisia, in June 2020.* The 17 full papers and 23 short papers presented in this volume were carefully reviewed and selected from 49 submissions. They cover topics such as: IoT and AI solutions for e-health; biomedical and health informatics; behavior and activity monitoring; behavior and activity monitoring; and wellbeing technology. *This conference was held virtually due to the COVID-19 pandemic

The Impact of Digital Technologies on Public Health in Developed and Developing Countries

This open access book constitutes the refereed proceedings of the 18th International Conference on String Processing and Information Retrieval, ICOST 2020, held in Hammamet, Tunisia, in June 2020.* The 17 full papers and 23 short papers presented in this volume were carefully reviewed and selected from 49 submissions. They cover topics such as: IoT and AI solutions for e-health; biomedical and health informatics; behavior and activity monitoring; behavior and activity monitoring; and wellbeing technology. *This conference was held virtually due to the COVID-19 pandemic

Application of Asynchronous Transfer Mode (Atm) technology to Picture Archiving and Communication Systems (Pacs): A survey

Broadband Integrated Services Digital Network (R-ISDN) provides a range of narrowband and broad-band services for voice, video, and multimedia. Asynchronous Transfer Mode (ATM) has been selected by the standards bodies as the transfer mode for implementing B-ISDN; The ability to digitize images has lead to the prospect of reducing the physical space requirements, material costs, and manual labor of traditional film handling tasks in hospitals. The system which handles the acquisition, storage, and transmission of medical images is called a Picture Archiving and Communication System (PACS). The transmission system will directly impact the speed of image transfer. Today the most common transmission means used by acquisition and display station products is Ethernet. However, when considering network media, it is important to consider what the long term needs will be. Although ATM is a new standard, it is showing signs of becoming the next logical step to meet the needs of high speed networks; This thesis is a survey on ATM, and PACS. All the concepts involved in developing a PACS are presented in an orderly manner. It presents the recent developments in ATM, its applicability to PACS and the issues to be resolved for realising an ATM-based complete PACS. This work will be useful in providing the latest information, for any future research on ATM-based networks, and PACS

Diversity and Diversification Across the Global Radiation of Extant Bats

Diversity is not distributed equally across the tree of life. This fundamental observation is central to ecology and evolutionary biology, and spans both spatial and temporal scales. Species richness, for example, is unevenly distributed both within and across clades. Biodiversity is often spatially concentrated in the tropics, with lower richness in temperate biomes. Some clades are characterized by extremely high ecological and morphological diversity, while others remain static across geologic timescales. This dissertation highlights these patterns of diversity across extant bats, the Order Chiroptera, and seeks to understand the evolutionary processes of diversification that govern them. Chapter 1 serves as both an introduction to the major questions of the dissertation and an overview of extant bat diversity, and how it varies spatially, phylogenetically, and ecologically across the globe. In this chapter, I primarily focus on spatial variation in regional richness patterns, and on the major differences between temperate and tropical bat diversity. In Chapter 2, I assemble a species-level molecular phylogeny of the order that is time-calibrated with fossil data. Using this phylogeny, I infer speciation dynamics across the order, and find that despite the imbalances in species richness, speciation rates are relatively homogeneous. I only infer strong evidence for more rapid rates within the subfamily Stenodermatinae, a clade of Neotropical phyllostomid bats. In Chapter 3, I develop models to test whether bat species co-occurrence is constrained by relatedness or ecomorphological similarity. Contrary to theoretical predictions and results from other major clades, I find that neither of these metrics of divergence controls co-occurrence in sympatry across most bats and realms. The only exception is the Neotropical realm, where bat species are most likely to co-occur when they are the most ecomorphologically similar to one another. This potentially indicates that Neotropical bat communities and species pools, at broad regional scales, are sorted by filtering processes that cluster bats with similar ecologies together in space. For Chapters 4 and 5, I assess how ecology and morphology are linked in New World bats. Chapter 4 describes an open-access, X-ray computed microtomography database of bat skulls, and how this resource can be used by the broader scientific and educational community. Chapter 5 combines crania from that database with diet data across New World bats, and tests whether ecological and morphological evolution are correlated in this group. Surprisingly, I find that patterns of ecological, trophic evolution are largely decoupled from morphological evolution. There is considerable heterogeneity in how readily different clades transition among trophic guilds, yet cranial shape evolution is surprisingly homogeneous. This decoupled pattern is potentially driven by underestimated trophic plasticity and omnivory among noctilionoid bats, as well as high lability among bat crania. Finally, in Chapter 6, I conclude with a summary of our major findings, and some thoughts on ecological and macroevolutionary inference both within bats and across the tree of life.PHDEcology and Evolutionary BiologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145993/1/jeffjshi_1.pd

Secure VoIP Performance Measurement

This project presents a mechanism for instrumentation of secure VoIP calls. The experiments were run under different network conditions and security systems. VoIP services such as Google Talk, Express Talk and Skype were under test. The project allowed analysis of the voice quality of the VoIP services based on the Mean Opinion Score (MOS) values generated by Perceptual valuation of Speech Quality (PESQ). The quality of the audio streams produced were subjected to end-to-end delay, jitter, packet loss and extra processing in the networking hardware and end devices due to Internetworking Layer security or Transport Layer security implementations. The MOS values were mapped to Perceptual Evaluation of Speech Quality for wideband (PESQ-WB) scores. From these PESQ-WB scores, the graphs of the mean of 10 runs and box and whisker plots for each parameter were drawn. Analysis on the graphs was performed in order to deduce the quality of each VoIP service. The E-model was used to predict the network readiness and Common vulnerability Scoring System (CVSS) was used to predict the network vulnerabilities. The project also provided the mechanism to measure the throughput for each test case. The overall performance of each VoIP service was determined by PESQ-WB scores, CVSS scores and the throughput. The experiment demonstrated the relationship among VoIP performance, VoIP security and VoIP service type. The experiment also suggested that, when compared to an unsecure IPIP tunnel, Internetworking Layer security like IPSec ESP or Transport Layer security like OpenVPN TLS would improve a VoIP security by reducing the vulnerabilities of the media part of the VoIP signal. Morever, adding a security layer has little impact on the VoIP voice quality

Switching techniques for broadband ISDN

The properties of switching techniques suitable for use in broadband networks have been investigated. Methods for evaluating the performance of such switches have been reviewed. A notation has been introduced to describe a class of binary self-routing networks. Hence a technique has been developed for determining the nature of the equivalence between two networks drawn from this class. The necessary and sufficient condition for two packets not to collide in a binary self-routing network has been obtained. This has been used to prove the non-blocking property of the Batcher-banyan switch. A condition for a three-stage network with channel grouping and link speed-up to be nonblocking has been obtained, of which previous conditions are special cases. A new three-stage switch architecture has been proposed, based upon a novel cell-level algorithm for path allocation in the intermediate stage of the switch. The algorithm is suited to hardware implementation using parallelism to achieve a very short execution time. An array of processors is required to implement the algorithm The processor has been shown to be of simple design. It must be initialised with a count representing the number of cells requesting a given output module. A fast method has been described for performing the request counting using a non-blocking binary self-routing network. Hardware is also required to forward routing tags from the processors to the appropriate data cells, when they have been allocated a path through the intermediate stage. A method of distributing these routing tags by means of a non-blocking copy network has been presented. The performance of the new path allocation algorithm has been determined by simulation. The rate of cell loss can increase substantially in a three-stage switch when the output modules are non-uniformly loaded. It has been shown that the appropriate use of channel grouping in the intermediate stage of the switch can reduce the effect of non-uniform loading on performance