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Proceedings of the Fourth Berkeley Conference on Distributed Data Management and Computer Networks
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Contextually and identity aware 5G services
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonThe fifth generation (5G) mobile networks aim to be ten times faster than the existing 4G connection, whilst providing low latency, and flexibility. Hence, various alterations are planned to the existing network infrastructure to be able to reach the 5G expected performance levels. The main technologies that were used, to ensure high performance, flexible network, and efficient resource allocation, are Software Defined Network and Network Function Virtualization. As these technologies are replacing the device-based architecture with, a service-based architecture.
This thesis provides a design of location database interactive web interface and interactive mobile application. The implementation of real time video streaming location server, the streaming system's performance parameters demonstrated a high level of QoS (0.07ms jitter and 9.53ms delay). In regard to experimental examination, it measured the localisation coverage, accuracy measurements and a highly scalable security solution. The localisation coverage and accuracy measurements were achieved through the mmWave and VLC link transmitters. The proposed simulated annealing algorithm aimed at data optimisation for location measurements accuracy showed results of the average location error of x and y which showed significant improvement from x= 22.5 and y=21.6 to x=11.09 and y= 11.63.
The proposed indoor location security solution showed significant results, as it provides a high scalability solution using the VNF. The solution showed that it was not 100% effective, as some of the fake discover packets still reached the DHCP server. This was due to the high load of traffic passing through the network. Nonetheless, 90% of the fake DHCP discover packets never reached the DHCP server because the scripts began blocking all fake discover packets after realising it was an attack. This conveys that the proposed system was able to run successfully without crashing or overloading the controller.
Overall, the main challenges facing 5G have been addressed with their proposed solutions, which showed promising results. Conclusively showing that there is a lot more space for technological advancements to support the future of mobile networks.European Union’s Horizon 2020 research program - the Internet of Radio-Light (IoRL) project H2020-ICT 761992
A comparison of some performance evaluation techniques
In this thesis we look at three approaches to modelling interactive computer systems: Simulation, Operational analysis and Performance-Oriented design. The simulation approach, presented first, is applied to a general purpose, multiprogrammed, machine independent, virtual memory computer system. The model is used to study the effects of different performance parameters upon important performance indices. It is also used to compare or validate the results produced by the other two methods. The major drawback of the simulation model (i.e. its relatively high cost) has been overcome by combining regression techniques with simulation, using simple experimental case studies. Next, operational analysis was reviewed in a hierarchical way (starting by analysing a single-resource queue and ending up by analysing a multi-class customer general interactive system), to study the performance model of general interactive systems. The results of the model were compared with the performance indices produced using the simulation results. The performance-oriented design technique was the third method used for building system performance models. Here, several optimization design problems have been reviewed to minimize the response time or maximize the system throughput subject to a cost constraint. Again, the model results were compared with the simulation results using different cost constraints. We suggest finally, that the above methods should be used together to assist the designer in building computer performance models
Beyond Transmitting Bits: Context, Semantics, and Task-Oriented Communications
Communication systems to date primarily aim at reliably communicating bit sequences. Such an approach provides efficient engineering designs that are agnostic to the meanings of the messages or to the goal that the message exchange aims to achieve. Next generation systems, however, can be potentially enriched by folding message semantics and goals of communication into their design. Further, these systems can be made cognizant of the context in which communication exchange takes place, thereby providing avenues for novel design insights. This tutorial summarizes the efforts to date, starting from its early adaptations, semantic-aware and task-oriented communications, covering the foundations, algorithms and potential implementations. The focus is on approaches that utilize information theory to provide the foundations, as well as the significant role of learning in semantics and task-aware communications
Beyond Transmitting Bits: Context, Semantics, and Task-Oriented Communications
Communication systems to date primarily aim at reliably communicating bit
sequences. Such an approach provides efficient engineering designs that are
agnostic to the meanings of the messages or to the goal that the message
exchange aims to achieve. Next generation systems, however, can be potentially
enriched by folding message semantics and goals of communication into their
design. Further, these systems can be made cognizant of the context in which
communication exchange takes place, providing avenues for novel design
insights. This tutorial summarizes the efforts to date, starting from its early
adaptations, semantic-aware and task-oriented communications, covering the
foundations, algorithms and potential implementations. The focus is on
approaches that utilize information theory to provide the foundations, as well
as the significant role of learning in semantics and task-aware communications.Comment: 28 pages, 14 figure
Обзор подходов к организации физического уровня в СУБД
In this paper we survey various DBMS physical design options. We will consider both vertical and horizontal partitioning, and briefly cover replication. This survey is not limited only to local systems, but also includes distributed ones. The latter adds a new interesting question — how to actually distribute data among several processing nodes. Aside from theoretical approaches we consider the practical ones, implemented in any contemporary DBMS. We cover these aspects not only from user, but also architect and programmer perspectives.В данной работе мы рассмотрели различные методы организации физического уровня СУБД: вертикальное и горизонтальное фрагментирование, а также вкратце нами затронут вопрос репликации. Указанные методы были рассмотрены не только для локальных, но и для распределенных СУБД. Последним было уделено повышенное внимание: были рассмотрены методы размещения данных на узлах распределенной системы. Кроме теоретических работ, приведены работы практического характера, в которых освещены вопросы применения вышеуказанных методов в современных коммерческих СУБД. Они были рассмотрены как с позиции пользователя, так и с позиций архитектора и программиста СУБ
Event processing in web of things
The incoming digital revolution has the potential to drastically improve our productivity,
reduce operational costs and improve the quality of the products. However, the realization
of these promises requires the convergence of technologies — from edge computing
to cloud, artificial intelligence, and the Internet of Things — blurring the lines between
the physical and digital worlds. Although these technologies evolved independently over
time, they are increasingly becoming intertwined. Their convergence will create an unprecedented
level of automation, achieved via massive machine-to-machine interactions
whose cornerstone are event processing tasks.
This thesis explores the intersection of these technologies by making an in-depth analysis
of their role in the life-cycle of event processing tasks, including their creation, placement
and execution. First, it surveys currently existing Web standards, Internet drafts,
and design patterns that are used in the creation of cloud-based event processing. Then, it
investigates the reasons for event processing to start shifting towards the edge, alongside
with the standards that are necessary for a smooth transition to occur. Finally, this work
proposes the use of deep reinforcement learning methods for the placement and distribution
of event processing tasks at the edge. Obtained results show that the proposed
neural-based event placement method is capable of obtaining (near) optimal solutions in
several scenarios and provide hints about future research directions.A nova revolução digital promete melhorar drasticamente a nossa produtividade, reduzir
os custos operacionais e melhorar a qualidade dos produtos. A concretizac¸ ˜ao dessas promessas
requer a convergˆencia de tecnologias – desde edge computing à cloud, inteligência
artificial e Internet das coisas (IoT) – atenuando a linha que separa o mundo físico do digital.
Embora as quatro tecnologias mencionadas tenham evoluído de forma independente
ao longo do tempo, atualmente elas estão cada vez mais interligadas. A convergência destas
tecnologias irá criar um nível de automatização sem precedentes.The research published in this work was supported by the Portuguese Foundation for
Science and Technology (FCT) through CEOT (Center for Electronic, Optoelectronic and
Telecommunications) funding (UID/MULTI/00631/2020) and by FCT Ph.D grant to Andriy
Mazayev (SFRH/BD/138836/2018)
Second year technical report on-board processing for future satellite communications systems
Advanced baseband and microwave switching techniques for large domestic communications satellites operating in the 30/20 GHz frequency bands are discussed. The nominal baseband processor throughput is one million packets per second (1.6 Gb/s) from one thousand T1 carrier rate customer premises terminals. A frequency reuse factor of sixteen is assumed by using 16 spot antenna beams with the same 100 MHz bandwidth per beam and a modulation with a one b/s per Hz bandwidth efficiency. Eight of the beams are fixed on major metropolitan areas and eight are scanning beams which periodically cover the remainder of the U.S. under dynamic control. User signals are regenerated (demodulated/remodulated) and message packages are reformatted on board. Frequency division multiple access and time division multiplex are employed on the uplinks and downlinks, respectively, for terminals within the coverage area and dwell interval of a scanning beam. Link establishment and packet routing protocols are defined. Also described is a detailed design of a separate 100 x 100 microwave switch capable of handling nonregenerated signals occupying the remaining 2.4 GHz bandwidth with 60 dB of isolation, at an estimated weight and power consumption of approximately 400 kg and 100 W, respectively
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