BCOOL: A novel blockchain congestion control architecture using dynamic service function chaining and machine learning for next generation vehicular networks

ABSTRACT: This paper presents the first, novel, dynamic, resilient, and consistent Blockchain COngestion ContrOL (BCOOL) system for vehicular networks that fills the gap of trustworthy Blockchain congestion prediction systems. BCOOL relies on the heterogeneity of Machine Learning, Software-Defined Networks and Network Function Virtualization that is customized in three hybrid cloud/edge-based On/Offchain smart contract modules and ruled by an efficient and reliable communication protocol. BCOOL’s first novel module aims at managing message and vehicle trustworthiness using a novel, dynamic and hybrid Blockchain Fogbased Distributed Trust Contract Strategy (FDTCS). The second novel module accurately and proactively predicts the occurrence of congestion, ahead of time, using a novel Hybrid On/Off-Chain Multiple Linear Regression Software-defined Contract Strategy (HOMLRCS). This module presents a virtualization facility layer to the third novel K-means/Random Forest-based On/Off-Chain Dynamic Service Function Chaining Contract Strategy (KRF-ODSFCS) that dynamically, securely and proactively predicts VNF placements and their chaining order in the context of SFCs w.r.t users’ dynamic QoS priority demands. BCOOL exhibits a linear complexity and a strong resilience to failures. Simulation results show that BCOOL outperforms the next best comparable strategies by 80% and 100% reliability and efficiency gains in challenging data congestion environments. This yields to fast, reliable and accurate congestion prediction decisions, ahead of time, and optimizes transaction validation processing time. Globally, the Byzantine resilience, complexity and attack mitigation strategies along with simulation results prove that BCOOL securely predicts the congestion and provides real-time monitoring, fast and accurate SFC deployment decisions while lowering both capital and operational expenditures (CAPEX/OPEX) costs

Power aware resource allocation and virtualization algorithms for 5G core networks

Most of the algorithms that solved the resource allocation problem, used to apply greedy algorithms to select the physical nodes and shortest paths to select the physical edges, without sufficient coordination between selecting the physical nodes and edges. This lack of coordination may degrade the overall acceptance ratios and network performance as whole, in addition, that may include non-necessary physical resources, which will consume more power and computational processing capacities, as well as cause more delays. Therefore, the main objective of this PhD thesis is to develop power aware resource allocation and virtualization algorithms for 5G core networks, which will be achieved through developing a virtualization resource allocation technique to perform virtual nodes and edges allocations in full coordination, and on the least physical resources. The algorithms will be general and solve the resource allocation problem for virtual network embedding and network function virtualization frameworks, while minimizing the total consumed power in the physical network, and consider end-to-end delay and migration as new optional features. This thesis suggested to solve the power aware resource allocation problem through brand new algorithms adopting a new technique called segmentation, which fully coordinates allocating the virtual nodes and edges together, and guarantees to use the very least physical resources to minimize the total power consumption, through consolidating the virtual machines into least number of nodes as much as possible. The proposed algorithms, solves virtual network embedding problem for off-line and on-line scenarios, and solves resource allocations for network function virtualization environment for off-line, on-line, and migration scenarios. The evaluations of the proposed off-line virtual network embedding algorithm, PaCoVNE, showed that it managed to save physical network power consumption by 57% in average, and the on-line algorithm, oPaCoVNE, managed to minimize the average power consumption in the physical network by 24% in average. Regarding allocation times of PaCoVNE and oPaCoVNE, they were in the ranges of 20-40 ms. For network function virtualization environment, the evaluations of the proposed offline NFV power aware algorithm, PaNFV, showed that on average it had lower total costs and lower migration cost by 32% and 65:5% respectively, compared to the state-of-art algorithms, while the on-line algorithm, oPaNFV, managed to allocate the Network Services in average times of 60 ms, and it had very negligible migrations. Nevertheless, this thesis suggests that future enhancements for the proposed algorithms need to be focused around modifying the proposed segmentation technique to solve the resource allocation problem for multiple paths, in addition to consider power aware network slicing, especially for mobile edge computing, and modify the algorithms for application aware resource allocations for very large scale networks. Moreover, future work can modify the segmentation technique and the proposed algorithms, by integrating machine learning techniques for smart traffic and optimal paths prediction, as well as applying machine learning for better energy efficiency, faster load balancing, much accurate resource allocations based on verity of quality of service metrics.La mayoría de los algoritmos que resolvieron el problema de asignación de recursos, se utilizaron para aplicar algoritmos codiciosos para seleccionar los nodos físicos y las rutas más cortas para seleccionar los bordes físicos, sin una coordinación suficiente entre la selección de los nodos físicos y los bordes. Esta falta de coordinación puede degradar los índices de aceptación generales y el rendimiento de la red en su totalidad, además, que puede incluir recursos físicos no necesarios, que consumirán más potencia y capacidades de procesamiento computacional, además de causar más retrasos. Por lo tanto, el objetivo principal de esta tesis doctoral es desarrollar algoritmos de virtualización y asignación de recursos para las redes centrales 5G, que se lograrán mediante el desarrollo de una técnica de asignación de recursos de virtualización para realizar nodos virtuales y asignaciones de bordes en total coordinación, y al menos recursos físicos. Los algoritmos serán generales y resolverán el problema de asignación de recursos para la integración de redes virtuales y los marcos de virtualización de funciones de red, al tiempo que minimizan la potencia total consumida en la red física y consideran el retraso y la migración de extremo a extremo como nuevas características opcionales. Esta tesis sugirió resolver el problema de la asignación de recursos conscientes de la potencia a través de nuevos algoritmos que adoptan una nueva técnica llamada segmentación, que coordina completamente la asignación de los nodos virtuales y los bordes, y garantiza el uso de los recursos físicos mínimos para minimizar el consumo total de energía, a través de consolidar las máquinas virtuales en el menor número de nodos tanto como sea posible. Los algoritmos propuestos solucionan el problema de integración de la red virtual para los escenarios sin conexión y en línea, y resuelve las asignaciones de recursos para el entorno de virtualización de la función de red para los escenarios sin conexión, en línea y de migración. Las evaluaciones del algoritmo de integración de red virtual sin conexión propuesto, PaCoVNE, mostraron que logró ahorrar el consumo de energía de la red física en un 57% en promedio, y el algoritmo en línea, oPaCoVNE, logró minimizar el consumo de energía promedio en la red física en un 24% en promedio. Con respecto a los tiempos de asignación de PaCoVNE y oPaCoVNE, estuvieron en los rangos de 20-40 ms. Para el entorno de virtualización de la función de red, las evaluaciones del algoritmo consciente de la potencia NFV sin conexión propuesto, PaNFV, mostraron que, en promedio, tenía menores costos totales y menores costos de migración en un 32% y 65: 5% respectivamente, en comparación con el estado de la técnica. Los algoritmos, mientras que el algoritmo en línea, oPaNFV, logró asignar los Servicios de Red en tiempos promedio de 60 ms, y tuvo migraciones muy insignificantes. Sin embargo, esta tesis sugiere que las futuras mejoras para los algoritmos propuestos deben centrarse en modificar la técnica de segmentación propuesta para resolver el problema de asignación de recursos para múltiples rutas, además de considerar el corte de la red que requiere energía, especialmente para la computación de borde móvil, y modificar el Algoritmos para asignaciones de recursos conscientes de la aplicación para redes de gran escala. Además, el trabajo futuro puede modificar la técnica de segmentación y los algoritmos propuestos, mediante la integración de técnicas de aprendizaje automático para el tráfico inteligente y la predicción de rutas óptimas, así como la aplicación del aprendizaje automático para una mejor eficiencia energética, un equilibrio de carga más rápido, asignaciones de recursos mucho más precisas basadas en la veracidad de Métricas de calidad de servicio

Admission Control Optimisation for QoS and QoE Enhancement in Future Networks

Recent exponential growth in demand for traffic heterogeneity support and the number of associated devices has considerably increased demand for network resources and induced numerous challenges for the networks, such as bottleneck congestion, and inefficient admission control and resource allocation. Challenges such as these degrade network Quality of Service (QoS) and user-perceived Quality of Experience (QoE). This work studies admission control from various perspectives. For example, two novel single-objective optimisation-based admission control models, Dynamica Slice Allocation and Admission Control (DSAAC) and Signalling and Admission Control (SAC), are presented to enhance future limited-capacity network Grade of Service (GoS), and for control signalling optimisation, respectively. DSAAC is an integrated model whereby a cost-estimation function based on user demand and network capacity quantifies resource allocation among users. Moreover, to maximise resource utility, adjustable minimum and maximum slice resource bounds have also been derived. In the case of user blocking from the primary slice due to congestion or resource scarcity, a set of optimisation algorithms on inter-slice admission control and resource allocation and adaptability of slice elasticity have been proposed. A novel SAC model uses an unsupervised learning technique (i.e. Ranking-based clustering) for optimal clustering based on users’ homogeneous demand characteristics to minimise signalling redundancy in the access network. The redundant signalling reduction reduces the additional burden on the network in terms of unnecessary resource utilisation and computational time. Moreover, dynamically reconfigurable QoE-based slice performance bounds are also derived in the SAC model from multiple demand characteristics for clustered user admission to the optimal network. A set of optimisation algorithms are also proposed to attain efficient slice allocation and users’ QoE enhancement via assessing the capability of slice QoE elasticity. An enhancement of the SAC model is proposed through a novel multi-objective optimisation model named Edge Redundancy Minimisation and Admission Control (E-RMAC). A novel E-RMAC model for the first time considers the issue of redundant signalling between the edge and core networks. This model minimises redundant signalling using two classical unsupervised learning algorithms, K-mean and Ranking-based clustering, and maximises the efficiency of the link (bandwidth resources) between the edge and core networks. For multi-operator environments such as Open-RAN, a novel Forecasting and Admission Control (FAC) model for tenant-aware network selection and configuration is proposed. The model features a dynamic demand-estimation scheme embedded with fuzzy-logic-based optimisation for optimal network selection and admission control. FAC for the first time considers the coexistence of the various heterogeneous cellular technologies (2G, 3G,4G, and 5G) and their integration to enhance overall network throughput by efficient resource allocation and utilisation within a multi-operator environment. A QoS/QoE-based service monitoring feature is also presented to update the demand estimates with the support of a forecasting modifier. he provided service monitoring feature helps resource allocation to tenants, approximately closer to the actual demand of the tenants, to improve tenant-acquired QoE and overall network performance. Foremost, a novel and dynamic admission control model named Slice Congestion and Admission Control (SCAC) is also presented in this thesis. SCAC employs machine learning (i.e. unsupervised, reinforcement, and transfer learning) and multi-objective optimisation techniques (i.e. Non-dominated Sorting Genetic Algorithm II ) to minimise bottleneck and intra-slice congestion. Knowledge transfer among requests in form of coefficients has been employed for the first time for optimal slice requests queuing. A unified cost estimation function is also derived in this model for slice selection to ensure fairness among slice request admission. In view of instantaneous network circumstances and load, a reinforcement learning-based admission control policy is established for taking appropriate action on guaranteed soft and best-effort slice requests admissions. Intra-slice, as well as inter-slice resource allocation, along with the adaptability of slice elasticity, are also proposed for maximising slice acceptance ratio and resource utilisation. Extensive simulation results are obtained and compared with similar models found in the literature. The proposed E-RMAC model is 35% superior at reducing redundant signalling between the edge and core networks compared to recent work. The E-RMAC model reduces the complexity from O(U) to O(R) for service signalling and O(N) for resource signalling. This represents a significant saving in the uplink control plane signalling and link capacity compared to the results found in the existing literature. Similarly, the SCAC model reduces bottleneck congestion by approximately 56% over the entire load compared to ground truth and increases the slice acceptance ratio. Inter-slice admission and resource allocation offer admission gain of 25% and 51% over cooperative slice- and intra-slice-based admission control and resource allocation, respectively. Detailed analysis of the results obtained suggests that the proposed models can efficiently manage future heterogeneous traffic flow in terms of enhanced throughput, maximum network resources utilisation, better admission gain, and congestion control

Optimization and Communication in UAV Networks

UAVs are becoming a reality and attract increasing attention. They can be remotely controlled or completely autonomous and be used alone or as a fleet and in a large set of applications. They are constrained by hardware since they cannot be too heavy and rely on batteries. Their use still raises a large set of exciting new challenges in terms of trajectory optimization and positioning when they are used alone or in cooperation, and communication when they evolve in swarm, to name but a few examples. This book presents some new original contributions regarding UAV or UAV swarm optimization and communication aspects

A patient agent controlled customized blockchain based framework for internet of things

Although Blockchain implementations have emerged as revolutionary technologies for various industrial applications including cryptocurrencies, they have not been widely deployed to store data streaming from sensors to remote servers in architectures known as Internet of Things. New Blockchain for the Internet of Things models promise secure solutions for eHealth, smart cities, and other applications. These models pave the way for continuous monitoring of patient’s physiological signs with wearable sensors to augment traditional medical practice without recourse to storing data with a trusted authority. However, existing Blockchain algorithms cannot accommodate the huge volumes, security, and privacy requirements of health data. In this thesis, our first contribution is an End-to-End secure eHealth architecture that introduces an intelligent Patient Centric Agent. The Patient Centric Agent executing on dedicated hardware manages the storage and access of streams of sensors generated health data, into a customized Blockchain and other less secure repositories. As IoT devices cannot host Blockchain technology due to their limited memory, power, and computational resources, the Patient Centric Agent coordinates and communicates with a private customized Blockchain on behalf of the wearable devices. While the adoption of a Patient Centric Agent offers solutions for addressing continuous monitoring of patients’ health, dealing with storage, data privacy and network security issues, the architecture is vulnerable to Denial of Services(DoS) and single point of failure attacks. To address this issue, we advance a second contribution; a decentralised eHealth system in which the Patient Centric Agent is replicated at three levels: Sensing Layer, NEAR Processing Layer and FAR Processing Layer. The functionalities of the Patient Centric Agent are customized to manage the tasks of the three levels. Simulations confirm protection of the architecture against DoS attacks. Few patients require all their health data to be stored in Blockchain repositories but instead need to select an appropriate storage medium for each chunk of data by matching their personal needs and preferences with features of candidate storage mediums. Motivated by this context, we advance third contribution; a recommendation model for health data storage that can accommodate patient preferences and make storage decisions rapidly, in real-time, even with streamed data. The mapping between health data features and characteristics of each repository is learned using machine learning. The Blockchain’s capacity to make transactions and store records without central oversight enables its application for IoT networks outside health such as underwater IoT networks where the unattended nature of the nodes threatens their security and privacy. However, underwater IoT differs from ground IoT as acoustics signals are the communication media leading to high propagation delays, high error rates exacerbated by turbulent water currents. Our fourth contribution is a customized Blockchain leveraged framework with the model of Patient-Centric Agent renamed as Smart Agent for securely monitoring underwater IoT. Finally, the smart Agent has been investigated in developing an IoT smart home or cities monitoring framework. The key algorithms underpinning to each contribution have been implemented and analysed using simulators.Doctor of Philosoph