Métodos y Herramientas para el Diseño y Verificación de Sistemas de Comunicaciones Móviles

El objetivo de esta Tesis ha sido la consecución de tecnología para el diseño y mantenimiento eficientes, en coste temporal y económico, de Sistemas de Pruebas para equipos de comunicaciones inalámbricas. El proceso de diseño elaborado se ha basado en un conjunto de principios básicos: uso de lenguajes y notaciones ITU, independencia de la plataforma de ejecución y uso de herramientas comerciales. En esta Tesis se describe: a) Una arquitectura genérica para Sistemas de Pruebas. b) Una Metodología de Diseño de Sistemas de Pruebas. c) Un conjunto de herramientas de soporte. d) Una propuesta de metodología para el modelado con SDL. e) La aplicación a Sistemas de Pruebas de capa física de la arquitectura, métodos y herramientas utilizados en el área de protocolos. f) Un conjunto de implementaciones que validan las aportaciones anteriores

Protocol security for third generation telecommunication systems

In this thesis, a novel protocol stack architecture is presented. The Future Core Networks System (FCNS) forms a secure reference model for use in packet-switched structures, with its applicability ranging from computer to telecommunication networks. An insight on currently used network protocol systems is given, analysing standardised sets of communication rules with respect to the security they afford to the messages exchanged. The lack of protection schemes for the internal protocol stack messages and the implementation pitfalls of their security architectures are described, in relation to the effects they have on the communication process. The OSI security model is also considered, with disadvantages identified in the placement of security functionality and its management. The drawbacks depicted for currently used systems form the motivation behind this work. The analysis of the FCNS follows, which is composed of three parts. In the first part, the FCNS communication layers are examined, with respect to the mechanisms used to establish, maintain and tear down a connection between peer entities. In the second part, the security mechanisms of the proposed reference architecture are given, including details on the FCNS keystream generator used for the security of the internal FCNS messages. Finally, the FCNS Error Protocol is depicted, illustrating the modes of operation and advantages it exhibits over currently used systems. The work then moves into presenting details of the software FCNS implementation, followed by the presentation of the results and measurements obtained by the case studies created. Comparisons are given in relation to the TCP/IP suite, to provide the means of identifying the FCNS applicability in various network environments. The work is concluded by presenting the FCNS functionality in delivering information for the UMTS, together with further work that may enhance the flexibility and use of the proposed architecture

Measurement and Optimization of LTE Performance

4G Long Term Evolution (LTE) mobile system is the fourth generation communication system adopted worldwide to provide high-speed data connections and high-quality voice calls. Given the recent deployment by mobile service providers, unlike GSM and UMTS, LTE can be still considered to be in its early stages and therefore many topics still raise great interest among the international scientific research community: network performance assessment, network optimization, selective scheduling, interference management and coexistence with other communication systems in the unlicensed band, methods to evaluate human exposure to electromagnetic radiation are, as a matter of fact, still open issues. In this work techniques adopted to increase LTE radio performances are investigated. One of the most wide-spread solutions proposed by the standard is to implement MIMO techniques and within a few years, to overcome the scarcity of spectrum, LTE network operators will offload data traffic by accessing the unlicensed 5 GHz frequency. Our Research deals with an evaluation of 3GPP standard in a real test best scenario to evaluate network behavior and performance

Protocol security for third generation telecommunication systems

In this thesis, a novel protocol stack architecture is presented. The Future Core Networks System (FCNS) forms a secure reference model for use in packet-switched structures, with its applicability ranging from computer to telecommunication networks. An insight on currently used network protocol systems is given, analysing standardised sets of communication rules with respect to the security they afford to the messages exchanged. The lack of protection schemes for the internal protocol stack messages and the implementation pitfalls of their security architectures are described, in relation to the effects they have on the communication process. The OSI security model is also considered, with disadvantages identified in the placement of security functionality and its management. The drawbacks depicted for currently used systems form the motivation behind this work. The analysis of the FCNS follows, which is composed of three parts. In the first part, the FCNS communication layers are examined, with respect to the mechanisms used to establish, maintain and tear down a connection between peer entities. In the second part, the security mechanisms of the proposed reference architecture are given, including details on the FCNS keystream generator used for the security of the internal FCNS messages. Finally, the FCNS Error Protocol is depicted, illustrating the modes of operation and advantages it exhibits over currently used systems. The work then moves into presenting details of the software FCNS implementation, followed by the presentation of the results and measurements obtained by the case studies created. Comparisons are given in relation to the TCP/IP suite, to provide the means of identifying the FCNS applicability in various network environments. The work is concluded by presenting the FCNS functionality in delivering information for the UMTS, together with further work that may enhance the flexibility and use of the proposed architecture.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

A Methodology for Analyzing Power Consumption in Wireless Communication Systems

Energy usage has become an important issue in wireless communication systems. The energy-intensive nature of wireless communication has spurred concern over how best systems can make the most use of this non-renewable resource. Research in energy-efficient design of wireless communication systems show that one of its challenges is that the overall performance of the system depends, in a coupled way, on the different submodules of the system i.e. antenna, power amplifier, modulation, error control coding, and network architecture. Network architecture implementation strategies offer protocol software implementors an opportunity of incorporating low-power strategies into the design of the network protocols used for data communication. This dissertation proposes a methodology that would allow a software protocol implementor to analyze the power consumption of a wireless communication system. The foundation of this methodology lies in the understanding of the formal specification of the wireless interface network architecture which can be used to predict the performance of the system. By extending this hypothesis, a protocol implementor can use the formal specification to derive the power consumption behaviour of the wireless system during a normal operation (transmission or reception of data). A high-level formalism like state-transition graphs, can be used to track the protocol processing behaviour and to derive the associated continuous-time Markov chains. Because of their diversity, Markov reward models(MRM) are used to model the power consumption associated with the different states of a specified protocol layer. The models are solved analytically using the Mobius performance and dependability tool. Using the MRM accumulation and utilization measures, a profile of the power consumption is generated. Results from the experiments on the protocol layers show the individual power consumption and utilization of the different states as well as the accumulated power consumption of different protocol layers when compared. Ultimately, the results from the reward model solution can be used in the energy-efficient design of wireless communication systems. Lastly, in order to get an idea of how wireless communication device companies handle issues of power consumption, we consulted with the wireless module engineers at Siemens Communication South Africa and present our findings on current practices in energy efficient protocol implementation

Embedded System Design

A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues

Embedded System Design

A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues

Discrete Event Simulations

Considered by many authors as a technique for modelling stochastic, dynamic and discretely evolving systems, this technique has gained widespread acceptance among the practitioners who want to represent and improve complex systems. Since DES is a technique applied in incredibly different areas, this book reflects many different points of view about DES, thus, all authors describe how it is understood and applied within their context of work, providing an extensive understanding of what DES is. It can be said that the name of the book itself reflects the plurality that these points of view represent. The book embraces a number of topics covering theory, methods and applications to a wide range of sectors and problem areas that have been categorised into five groups. As well as the previously explained variety of points of view concerning DES, there is one additional thing to remark about this book: its richness when talking about actual data or actual data based analysis. When most academic areas are lacking application cases, roughly the half part of the chapters included in this book deal with actual problems or at least are based on actual data. Thus, the editor firmly believes that this book will be interesting for both beginners and practitioners in the area of DES