Метод відновлення мережі у віртуалізованому середовищі

Представлено метод динамічного відновлення вузлів з відмо-вою, який використовує евристичну модель для визначенния оптимального місця міграції віртуалізованих функціональних вузлів з фізичного місця з відмовою. Розглядається проблема вибору місць розташування децентралізованих вузлів управління. Метод може застосовуватись при управлінні функціонуванням віртуалізованих мережевих функцій на фізичній інфраструктурі для мінімізації витрат оператора зв'язку та покращення якості обслуговування абонентів. Запропонований метод є загальним і може застосовуватись для різних систем.The method of dynamic node recovery is presented, that uses a heuristic model to determine the optimal migration place for virtualized functional nodes from a physical node with a failure. The problem of choosing the locations of decentralized manager nodes is considered. The method can be used for the control the operation of virtualized network functions on physical infrastructure to minimize operator costs and improve customer service quality. The proposed method is general and can be applied to different systems.Представлен метод динамического восстановления узлов с отказом, который использует эвристическую модель для определения оптимального места миграции виртуализированных функциональных узлов с физического узла с отказом. Рассматривается проблема выбора мест расположения децентрализованных узлов управления. Метод может применяться при управлении функционированием виртуализированных сетевых функций на физической инфраструктуре для минимизации затрат оператора связи и улучшения качества обслуживания абонентов. Предложенный метод является общим и может применяться для различных систем

Resilient BBU placement in 5G C-RAN over optical aggregation networks

The huge data demand envisioned for the 5G requires radical changes in the mobile network architecture and technology. Centralized radio access network (C-RAN) is introduced as a novel mobile network architecture, designed to effectively support the challenging requirements of the future 5G mobile networks. In C-RAN, BaseBand Units (BBUs) are physically separated from their corresponding radio remote heads (RRHs) and located in a central single physical location called BBU pool. The RRHs are connected to the BBU pool via the so-called fronthaul network. The “centralization” demonstrates remarkable benefits in terms of computational resources as well as power savings. Following this centralization, designing a survivable C-RAN becomes crucial as BBU pool and link failures might cause service outage for large number of users. In this paper, we propose three different approaches for the survivable BBU pool placement problem and traffic routing in C-RAN deployment over a 5G optical aggregation network. Namely, we define the following protection scenarios: (1) dedicated path protection, (2) dedicated BBU protection and (3) dedicated BBU and path protection. The three approaches are formalized as integer linear programming (ILP) problems. The ILPs objectives are to minimize the number of BBU pools, the number of used wavelengths and the baseband processing computational resources, in terms of giga operations per second. We provide numerical results to compare the aforementioned protection strategies considering different network topologies. The results show the effect of the latency and the transport–network capacity on the BBU placement. We show the trade-off between the centralization degree and the tight latency requirements. Moreover, we discuss important insights about considering the different objective functions for each protection approach

Dynamic Spectrum Reservation for CR Networks in the Presence of Channel Failures: Channel Allocation and Reliability Analysis

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] Providing channel access opportunities for new service requests and guaranteeing continuous connections for ongoing flows until service completion are two challenges for service provisioning in wireless networks. Channel failures, which are typically caused by hardware and software failures or/and by intrinsic instability in radio transmissions, can easily result in network performance degradation. In cognitive radio networks (CRNs), secondary transmissions are inherently vulnerable to connection breaks due to licensed users' arrivals as well as channel failures. To explore the advantages of channel reservation on performance improvement in error-prone channels, we propose and analyze a dynamic channel reservation (DCR) algorithm and a dynamic spectrum access (DSA) scheme with three access privilege variations. The key idea of the DCR algorithm is to reserve a dynamically adjustable number of channels for the interrupted services to maintain service retainability for ongoing users or to enhance channel availability for new users. Furthermore, the DCR algorithm is embedded in the DSA scheme enabling spectrum access of primary and secondary users with different access privileges based on access flexibility for licensed shared access. The performance of such a CRN in the presence of homogeneous and heterogeneous channel failures is investigated considering different channel failure and repair rates.The work of V. Pla was supported by the Spanish Ministry of Economy, Industry and Competitiveness under Grant TIN2013-47272-C2-1-R.Balapuwaduge, IAM.; Li, F.; Pla, V. (2018). Dynamic Spectrum Reservation for CR Networks in the Presence of Channel Failures: Channel Allocation and Reliability Analysis. IEEE Transactions on Wireless Communications. 17(2):882-898. https://doi.org/10.1109/TWC.2017.2772240S88289817

A System Perspective to Privacy, Security and Resilience in Mobile Applications

Mobile applications have changed our life so much, but they also create problems related to privacy which is one of basic human rights. Protection (or security) of privacy is an important issue in mobile applications owing to the high likelihood of privacy violation nowadays. This thesis is devoted to a fundamental study on the privacy issue in mobile applications. The overall objective of the thesis is to advance our understanding of privacy and its relevant concepts in the context of mobile applications. There are three specific objectives with this thesis. Objective 1 is to have a more comprehensive understanding of the concepts of privacy, security and resilience (PSR for short) along with their relationship in the context of mobile applications. Objective 2 is to develop the principles of design of a mobile application system with a satisfactory PSR. Objective 3 is to develop a demonstration system (PSR demo for short) to illustrate how the principles of design can be applied. A salient approach was taken in this thesis, that is based on a general knowledge architecture called FCBPSS (F: function, C: context, B: behavior, P: principle. SS: state and structure). An analysis of literature was conducted first, resulting in a classification of various privacies against the FCPBSS architecture, followed by developing a theory of privacy, protection of privacy (security), and resilience of the system that performs protection of privacy, PSR theory for short. The principles of design of a mobile application system based on the PSR theory were then developed, which are expected to guide the practice of developing a mobile application for satisfactory privacy protection. Finally, a demonstration system, regarding the doctor booking for minimum waiting time and energy consumption, was developed to issue how the PSR theory and design principles work. The main contribution of this thesis is the development of the concept of PSR, especially the relationship among privacy (P), security (S), and resilience (R), and a set of design rules to develop a mobile application based on the PSR theory

Aplicação de mecanismos baseados em broker para ligação de terminais a redes móveis

In recent years, mobile data traffic has been growing with the increase of equipments connected to the network. Due to user demand, network operators have to continuously upgrade their networks and keep the costs low. Nowadays, to do this upgrade, the operator needs to acquire new equipment, leading to a very high investment. 5G aims to provide more scalability and flexibility on the network. For this, the 5G system architecture is built based on a cloud-native, which means Service Based Architecture (SBA) in the core network. SBA aims to provide connectivity with all access technologies, introducing more redundancy in the control plane’s resiliency and operational efficiency. Additionaly, instead of using dedicated interfaces between each pair of interacting core functions, they now communicate through a Service-Based Interface (SBI), aiming for greater flexibility and simplicity. The OpenAirInterface (OAI) is an open-source software platform that aims to provide an approximation to the 3GPP standards of the 4G and 5G networks. This thesis provides a study of the impact of the SBA in the control plane. For that, we used an architecture that evolves the Evolved Packet Core (EPC) into a core network close to 5G Core (5GC) by introducing a broker. The broker is integrated between the modules in the control plane, wherein they have to order requests to communicate with each other. The proposed architecture consists of integrating the broker on the OAI platform, evaluating it, and comparing it with the original EPC.Nos últimos anos, o tráfego de dados móveis tem vindo a crescer com o aumento de equipamentos ligados à rede. Devido à demanda do utilizador, os operadores de rede necessitam de atualizar continuamente a sua rede e manter os custos baixos. Atualmente, para essa atualização, o operador precisa de adquirir novos equipamentos, tendo um investimento muito elevado. O 5G via fornecer maior escalabilidade e flexibilidade na rede. Para isso, a arquitetura do sistema 5G é construída com base numa nuvem nativa, o que significa uma arquitetura baseada em serviços na rede “core”. Este tipo de arquitetura visa fornecer conectividade independentemente da tecnologia de acesso, introduzindo maior redundância na resiliência no plano de controlo e eficiência operacional. Adicionalmente, ao invés de interfaces dedicadas entre cada par de funções de rede “core” intervenientes, as mesmas comunicam através de uma interface baseada em serviços, com vista a uma maior flexibilidade e simplicidade. OpenAirInterface (OAI) é uma plataforma de software de código aberto que visa fornecer uma aproximação aos padrões 3GPP das redes 4G e 5G. Esta dissertação fornece um estudo do impacto de uma arquitetura baseada em serviços no plano de controlo. Para isso, utilizou-se uma arquitetura que evolui o Evolved Packet Core (EPC) para uma rede “core” próxima da 5G Core (5GC), introduzindo um broker. Um broker é integrado entre os módulos do plano de controlo, no qual estes para comunicarem entre si necessitam de realizar pedidos. A abordagem utilizada consiste na integração de um broker na plataforma OAI, avaliando o seu impacto comparando com o EPC original.Mestrado em Engenharia de Computadores e Telemátic

Особливості обчислювальної інфраструктури для систем керування телекомунікаціями

У навчальному посібнику викладено основні положення методів організації обчислювальної інфраструктури для систем керування телекомунікаціями, що складається з елементів фізичної інформаційно-телекомунікаційної інфраструктури та віртуального обчислювального середовища. У навчальному міститься аналіз систем керування телекомунікація ми, значну увагу приділено задачам організації обчислювальних ресурсів та засобам забезпечення якісного обслуговування кінцевих користувачів мобільних телекомунікаційних мереж. Запропоновані рішення за рахунок систематизації та удосконалення методів керування процесом обслуговування у гетерогенному телекомунікаційному середовищі і адаптивного вибору обчислювальних ресурсів дозволяють забезпечити контрольоване використання ресурсів в умовах різнорідної структури сервісів, підвищення вимог до показників якості обслуговування та неперервного зростанням об’ємів трафіку. Навчальний посібник призначений для здобувачів ступеня магістр за спеціальністю 172 «Телекомунікації та радіотехніка», а також буде корисним для фахівців, які розробляють програмне забезпечення для телекомунікаційних систем.The training manual outlines the main provisions of the methods of organizing the computing infrastructure for telecommunications management systems, which consists of elements of the physical information and telecommunications infrastructure and a virtual computing environment. The study contains an analysis of telecommunication management systems, significant attention is paid to the tasks of organizing computing resources and means of ensuring quality service to end users of mobile telecommunication networks. The proposed solutions due to the systematization and improvement of the methods of managing the service process in a heterogeneous telecommunications environment and the adaptive selection of computing resources allow to ensure the controlled use of resources in the conditions of a heterogeneous structure of services, increasing the requirements for service quality indicators and continuous growth of traffic volumes. The study guide is intended for master's degree holders in the specialty 172 "Telecommunications and radio engineering", and will also be useful for specialists who develop software for telecommunication systems

On Service Resilience in Cloud-Native 5G Mobile Systems

International audienceTo cope with the tremendous growth in mobile data traffic on one hand, and the modest average revenue peruser on the other hand, mobile operators have been exploring network virtualization and cloud computing technologies to build cost-efficient and elastic mobile networks and to have them offered as a cloud service. In such cloud-based mobile networks,ensuring service resilience is an important challenge to tackle. Indeed, high availability and service reliability are importantrequirements of carrier grade, but not necessarily intrinsic features of cloud computing. Building a system that requiresthe five nines reliability on a platform that may not always grant it is therefore a hurdle. Effectively, in carrier cloud, serviceresilience can be heavily impacted by a failure of any network function (NF) running on a virtual machine (VM). In this paper,we introduce a framework, along with efficient and proactive restoration mechanisms, to ensure service resilience in carriercloud. As restoration of a NF failure impacts a potential number of users, adequate network overload control mechanisms are alsoproposed. A mathematical model is developed to evaluate the performance of the proposed mechanisms. The obtained resultsare encouraging and demonstrate that the proposed mechanisms efficiently achieve their design goals