11 research outputs found
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Mobile Edge Cloud: Intelligent deployment and services for 5G Indoor Network
This thesis was submitted for the award of doctor of Philosophy and was awarded by Brunel University LondonFifth-Generation (5G) mobile networks are expected to perform according to the stringent performance targets assigned by standardization committees. Therefore, significant changes are proposed to the network infrastructure to achieve the expected performance levels. Network Function Virtualization, cloud computing and Software Defined Networks are some of the main technologies being utilised to ensure flexible network design, with optimum performance and efficient resource utilization. The aforementioned technologies are shifting the network architecture into service-based rather device-based architecture. In this regard, this thesis provides experimental investigation, design, implementation and evaluation of various multimedia services along with integration design and caching solution for 5G indoor network. The multimedia services are targeting the enhancement of UEs’ Quality of Experience, by exploiting the intelligence offered by the synergy between SDN and NFV technologies, to design and develop new multimedia solutions with improved QoE. The caching solution is designed to achieve a good trade-off between latency reduction and resource utilization that satisfies efficient network performance and resource utilization. The proposed network integration design targets deploying IoRL gNB with its innovative intelligent services. It have successfully achieved lower overhead signalling compared to the traditional network architectures. Whilst all of the proposed solutions have proven to provide enhancement to the system performance, the testing results for the multimedia services showed high QoS performance parameters in the form of zero packet loss due to route switching, very high throughput and 0.03 ms jitter. The caching solution test results provided up to 300% server utilization improvement (based on the deployed scenario) with negligible extra delay cost (0.5ms). As for the proposed integration design, the quantification of the performance enhancement is represented by the amount of the reduced overhead signalling. In the case of Intra-secondary gNB handover within the same Main eNB, the back-haul signalling for the AMF was reduced 100% while the overall overhead signalling is reduced by 50% compared to traditional deployment architecture.European Union’s Horizon 2020 research progra
Edge computing infrastructure for 5G networks: a placement optimization solution
This thesis focuses on how to optimize the placement of the Edge Computing infrastructure for upcoming 5G networks. To this aim, the core contributions of this research are twofold: 1) a novel heuristic called Hybrid Simulated Annealing to tackle the NP-hard nature of the problem and, 2) a framework called EdgeON providing a practical tool for real-life deployment optimization.
In more detail, Edge Computing has grown into a key solution to 5G latency, reliability and scalability requirements. By bringing computing, storage and networking resources to the edge of the network, delay-sensitive applications, location-aware systems and upcoming real-time services leverage the benefits of a reduced physical and logical path between the end-user and the data or service host.
Nevertheless, the edge node placement problem raises critical concerns regarding deployment and operational expenditures (i.e., mainly due to the number of nodes to be deployed), current backhaul network capabilities and non-technical placement limitations. Common approaches to the placement of edge nodes are based on: Mobile Edge Computing (MEC), where the processing capabilities are deployed at the Radio Access Network nodes and Facility Location Problem variations, where a simplistic cost function is used to determine where to optimally place the infrastructure. However, these methods typically lack the flexibility to be used for edge node placement under the strict technical requirements identified for 5G networks. They fail to place resources at the network edge for 5G ultra-dense networking environments in a network-aware manner.
This doctoral thesis focuses on rigorously defining the Edge Node Placement Problem (ENPP) for 5G use cases and proposes a novel framework called EdgeON aiming at reducing the overall expenses when deploying and operating an Edge Computing network, taking into account the usage and characteristics of the in-place backhaul network and the strict requirements of a 5G-EC ecosystem. The developed framework implements several placement and optimization strategies thoroughly assessing its suitability to solve the network-aware ENPP. The core of the framework is an in-house developed heuristic called Hybrid Simulated Annealing (HSA), seeking to address the high complexity of the ENPP while avoiding the non-convergent behavior of other traditional heuristics (i.e., when applied to similar problems).
The findings of this work validate our approach to solve the network-aware ENPP, the effectiveness of the heuristic proposed and the overall applicability of EdgeON. Thorough performance evaluations were conducted on the core placement solutions implemented revealing the superiority of HSA when compared to widely used heuristics and common edge placement approaches (i.e., a MEC-based strategy). Furthermore, the practicality of EdgeON was tested through two main case studies placing services and virtual network functions over the previously optimally placed edge nodes.
Overall, our proposal is an easy-to-use, effective and fully extensible tool that can be used by operators seeking to optimize the placement of computing, storage and networking infrastructure at the users’ vicinity. Therefore, our main contributions not only set strong foundations towards a cost-effective deployment and operation of an Edge Computing network, but directly impact the feasibility of upcoming 5G services/use cases and the extensive existing research regarding the placement of services and even network service chains at the edge
Distribuição de vídeo para grupos de utilizadores em redes móveis heterogéneas19
The evolutions veri ed in mobile devices capabilities (storage capacity, screen
resolution, processor, etc.) over the last years led to a signi cant change
in mobile user behavior, with the consumption and creation of multimedia
content becoming more common, in particular video tra c. Consequently,
mobile operator networks, despite being the target of architectural evolutions
and improvements over several parameters (such as capacity, transmission
and reception performance, amongst others), also increasingly become more
frequently challenged by performance aspects associated to the nature of
video tra c, whether by the demanding requirements associated to that
service, or by its volume increase in such networks.
This Thesis proposes modi cations to the mobile architecture towards a more
e cient video broadcasting, de ning and developing mechanisms applicable
to the network, or to the mobile terminal. Particularly, heterogeneous
networks multicast IP mobility supported scenarios are focused, emphasizing
their application over di erent access technologies. The suggested changes
are applicable to mobile or static user scenarios, whether it performs the role
of receiver or source of the video tra c. Similarly, the de ned mechanisms
propose solutions targeting operators with di erent video broadcasting goals,
or whose networks have di erent characteristics. The pursued methodology
combined an experimental evaluation executed over physical testbeds,
with the mathematical evaluation using network simulation, allowing the
veri cation of its impact on the optimization of video reception in mobile
terminalsA evolução veri cada nas características dos dispositivos moveis (capacidade
de armazenamento, resolução do ecrã, processador, etc.) durante os
últimos anos levou a uma alteração signi cativa nos comportamentos dos
utilizadores, sendo agora comum o consumo e produção de conteúdos
multimédia envolvendo terminais móveis, em particular o tráfego vídeo.
Consequentemente, as redes de operador móvel, embora tendo também sido
alvo constante de evoluções arquitecturais e melhorias em vários parâmetros
(tais como capacidade, ritmo de transmissão/recepção, entre outros), vêemse
cada vez mais frequentemente desa adas por aspectos de desempenho
associados à natureza do tráfego de vídeo, seja pela exigência de requisitos
associados a esse serviço, quer pelo aumento do volume do mesmo nesse
tipo de redes.
Esta Tese propôe alterações à arquitetura móvel para a disseminação de vídeo
mais e ciente, de nindo e desenvolvendo mecanismos aplicáveis à rede, ou
ao utilizador móvel. Em particular, são focados cenários suportados por IP
multicast em redes móveis heterogéneas, isto é, com ênfase na aplicação
destes mecanismos sobre diferentes tecnologias de acesso. As alterações
sugeridas aplicam-se a cenários de utilizador estático ou móvel, sendo este a
fonte ou receptor do tráfego vídeo. Da mesma forma, são propostas soluções
tendo em vista operadores com diferentes objectivos de disseminação de
vídeo, ou cujas redes têm diferentes características. A metodologia utilizada
combinou a avaliação experimental em testbeds físicas com a avaliação
matemática em simulações de redes, e permitiu veri car o impacto sobre
a optimização da recepção de vídeo em terminais móveisPrograma Doutoral em Telecomunicaçõe
End-to-end Mobile Network Slicing
Wireless networks have gone through several years of evolution until now and will continue to do so in order to cater for the varying needs of its users. These demands are expected to continue to grow even more in the future, both in size and variability. Hence, the 5G technology needs to consider these variabilities in service demands and potential data explosion which could accompany users’ demands at the core of its architecture. For 5G mobile network to handle these foreseen challenges, network slicing \cite{c13} is seen as a potential path to tread as its standardization is progressing. In light of the proposed 5G network architecture and to support and end-to-end mobile network slicing, we implemented radio access network (RAN) slicing over a virtualized evolved Node B (eNodeB) and ensured multiple core network slices could communicate through it successfully. Our results, challenges and further research path are presented in this thesis report
Managing Event-Driven Applications in Heterogeneous Fog Infrastructures
The steady increase in digitalization propelled by the Internet of Things (IoT) has led to a deluge of generated data at unprecedented pace. Thereby, the promise to realize data-driven decision-making is a major innovation driver in a myriad of industries. Based on the widely used event processing paradigm, event-driven applications allow to analyze data in the form of event streams in order to extract relevant information in a timely manner. Most recently, graphical flow-based approaches in no-code event processing systems have been introduced to significantly lower technological entry barriers. This empowers non-technical citizen technologists to create event-driven applications comprised of multiple interconnected event-driven processing services. Still, today’s event-driven applications are focused on centralized cloud deployments that come with inevitable drawbacks, especially in the context of IoT scenarios that require fast results, are limited by the available bandwidth, or are bound by the regulations in terms of privacy and security. Despite recent advances in the area of fog computing which mitigate these shortcomings by extending the cloud and moving certain processing closer to the event source, these approaches are hardly established in existing systems. Inherent fog computing characteristics, especially the heterogeneity of resources alongside novel application management demands, particularly the aspects of geo-distribution and dynamic adaptation, pose challenges that are currently insufficiently addressed and hinder the transition to a next generation of no-code event processing systems.
The contributions of this thesis enable citizen technologists to manage event-driven applications in heterogeneous fog infrastructures along the application life cycle. Therefore, an approach for a holistic application management is proposed which abstracts citizen technologists from underlying technicalities. This allows to evolve present event processing systems and advances the democratization of event-driven application management in fog computing. Individual contributions of this thesis are summarized as follows:
1. A model, manifested in a geo-distributed system architecture, to semantically describe characteristics specific to node resources, event-driven applications and their management to blend application-centric and infrastructure-centric realms.
2. Concepts for geo-distributed deployment and operation of event-driven applications alongside strategies for flexible event stream management.
3. A methodology to support the evolution of event-driven applications including methods to dynamically reconfigure, migrate and offload individual event-driven processing services at run-time.
The contributions are introduced, applied and evaluated along two scenarios from the manufacturing and logistics domain
5G Multi-access Edge Computing: Security, Dependability, and Performance
The main innovation of the Fifth Generation (5G) of mobile networks is the
ability to provide novel services with new and stricter requirements. One of
the technologies that enable the new 5G services is the Multi-access Edge
Computing (MEC). MEC is a system composed of multiple devices with computing
and storage capabilities that are deployed at the edge of the network, i.e.,
close to the end users. MEC reduces latency and enables contextual information
and real-time awareness of the local environment. MEC also allows cloud
offloading and the reduction of traffic congestion. Performance is not the only
requirement that the new 5G services have. New mission-critical applications
also require high security and dependability. These three aspects (security,
dependability, and performance) are rarely addressed together. This survey
fills this gap and presents 5G MEC by addressing all these three aspects.
First, we overview the background knowledge on MEC by referring to the current
standardization efforts. Second, we individually present each aspect by
introducing the related taxonomy (important for the not expert on the aspect),
the state of the art, and the challenges on 5G MEC. Finally, we discuss the
challenges of jointly addressing the three aspects.Comment: 33 pages, 11 figures, 15 tables. This paper is under review at IEEE
Communications Surveys & Tutorials. Copyright IEEE 202
Integração do paradigma de cloud computing com a infraestrutura de rede do operador
Doutoramento em Engenharia InformáticaThe proliferation of Internet access allows that users have the possibility to use
services available directly through the Internet, which translates in a change of
the paradigm of using applications and in the way of communicating,
popularizing in this way the so-called cloud computing paradigm. Cloud
computing brings with it requirements at two different levels: at the cloud level,
usually relying in centralized data centers, where information technology and
network resources must be able to guarantee the demand of such services;
and at the access level, i.e., depending on the service being consumed,
different quality of service is required in the access network, which is a Network
Operator (NO) domain. In summary, there is an obvious network dependency.
However, the network has been playing a relatively minor role, mostly as a
provider of (best-effort) connectivity within the cloud and in the access network.
The work developed in this Thesis enables for the effective integration of cloud
and NO domains, allowing the required network support for cloud. We propose
a framework and a set of associated mechanisms for the integrated
management and control of cloud computing and NO domains to provide endto-
end services. Moreover, we elaborate a thorough study on the embedding of
virtual resources in this integrated environment. The study focuses on
maximizing the host of virtual resources on the physical infrastructure through
optimal embedding strategies (considering the initial allocation of resources as
well as adaptations through time), while at the same time minimizing the costs
associated to energy consumption, in single and multiple domains.
Furthermore, we explore how the NO can take advantage of the integrated
environment to host traditional network functions. In this sense, we study how
virtual network Service Functions (SFs) should be modelled and managed in a
cloud environment and enhance the framework accordingly.
A thorough evaluation of the proposed solutions was performed in the scope of
this Thesis, assessing their benefits. We implemented proof of concepts to
prove the added value, feasibility and easy deployment characteristics of the
proposed framework. Furthermore, the embedding strategies evaluation has
been performed through simulation and Integer Linear Programming (ILP)
solving tools, and it showed that it is possible to reduce the physical
infrastructure energy consumption without jeopardizing the virtual resources
acceptance. This fact can be further increased by allowing virtual resource
adaptation through time. However, one should have in mind the costs
associated to adaptation processes. The costs can be minimized, but the virtual
resource acceptance can be also reduced. This tradeoff has also been subject
of the work in this Thesis.A proliferação do acesso à Internet permite aos utilizadores usar serviços
disponibilizados diretamente através da Internet, o que se traduz numa
mudança de paradigma na forma de usar aplicações e na forma de comunicar,
popularizando desta forma o conceito denominado de cloud computing. Cloud
computing traz consigo requisitos a dois níveis: ao nível da própria cloud,
geralmente dependente de centros de dados centralizados, onde as
tecnologias de informação e recursos de rede têm que ser capazes de garantir
as exigências destes serviços; e ao nível do acesso, ou seja, dependendo do
serviço que esteja a ser consumido, são necessários diferentes níveis de
qualidade de serviço na rede de acesso, um domínio do operador de rede. Em
síntese, existe uma clara dependência da cloud na rede. No entanto, o papel
que a rede tem vindo a desempenhar neste âmbito é reduzido, sendo
principalmente um fornecedor de conectividade (best-effort) tanto no dominio
da cloud como no da rede de acesso.
O trabalho desenvolvido nesta Tese permite uma integração efetiva dos
domínios de cloud e operador de rede, dando assim à cloud o efetivo suporte
da rede. Para tal, apresentamos uma plataforma e um conjunto de
mecanismos associados para gestão e controlo integrado de domínios cloud
computing e operador de rede por forma a fornecer serviços fim-a-fim. Além
disso, elaboramos um estudo aprofundado sobre o mapeamento de recursos
virtuais neste ambiente integrado. O estudo centra-se na maximização da
incorporação de recursos virtuais na infraestrutura física por meio de
estratégias de mapeamento ótimas (considerando a alocação inicial de
recursos, bem como adaptações ao longo do tempo), enquanto que se
minimizam os custos associados ao consumo de energia. Este estudo é feito
para cenários de apenas um domínio e para cenários com múltiplos domínios.
Além disso, exploramos como o operador de rede pode aproveitar o referido
ambiente integrado para suportar funções de rede tradicionais. Neste sentido,
estudamos como as funções de rede virtualizadas devem ser modeladas e
geridas num ambiente cloud e estendemos a plataforma de acordo com este
conceito.
No âmbito desta Tese foi feita uma avaliação extensa das soluções propostas,
avaliando os seus benefícios. Implementámos provas de conceito por forma a
demonstrar as mais-valias, viabilidade e fácil implantação das soluções
propostas. Além disso, a avaliação das estratégias de mapeamento foi
realizada através de ferramentas de simulação e de programação linear inteira,
mostrando que é possível reduzir o consumo de energia da infraestrutura
física, sem comprometer a aceitação de recursos virtuais. Este aspeto pode
ser melhorado através da adaptação de recursos virtuais ao longo do tempo.
No entanto, deve-se ter em mente os custos associados aos processos de
adaptação. Os custos podem ser minimizados, mas isso implica uma redução
na aceitação de recursos virtuais. Esta compensação foi também um tema
abordado nesta Tese
Earth Observation Open Science and Innovation
geospatial analytics; social observatory; big earth data; open data; citizen science; open innovation; earth system science; crowdsourced geospatial data; citizen science; science in society; data scienc