Networks, Communication, and Computing Vol. 2

Networks, communications, and computing have become ubiquitous and inseparable parts of everyday life. This book is based on a Special Issue of the Algorithms journal, and it is devoted to the exploration of the many-faceted relationship of networks, communications, and computing. The included papers explore the current state-of-the-art research in these areas, with a particular interest in the interactions among the fields

Machine Learning for Unmanned Aerial System (UAS) Networking

Fueled by the advancement of 5G new radio (5G NR), rapid development has occurred in many fields. Compared with the conventional approaches, beamforming and network slicing enable 5G NR to have ten times decrease in latency, connection density, and experienced throughput than 4G long term evolution (4G LTE). These advantages pave the way for the evolution of Cyber-physical Systems (CPS) on a large scale. The reduction of consumption, the advancement of control engineering, and the simplification of Unmanned Aircraft System (UAS) enable the UAS networking deployment on a large scale to become feasible. The UAS networking can finish multiple complex missions simultaneously. However, the limitations of the conventional approaches are still a big challenge to make a trade-off between the massive management and efficient networking on a large scale. With 5G NR and machine learning, in this dissertation, my contributions can be summarized as the following: I proposed a novel Optimized Ad-hoc On-demand Distance Vector (OAODV) routing protocol to improve the throughput of Intra UAS networking. The novel routing protocol can reduce the system overhead and be efficient. To improve the security, I proposed a blockchain scheme to mitigate the malicious basestations for cellular connected UAS networking and a proof-of-traffic (PoT) to improve the efficiency of blockchain for UAS networking on a large scale. Inspired by the biological cell paradigm, I proposed the cell wall routing protocols for heterogeneous UAS networking. With 5G NR, the inter connections between UAS networking can strengthen the throughput and elasticity of UAS networking. With machine learning, the routing schedulings for intra- and inter- UAS networking can enhance the throughput of UAS networking on a large scale. The inter UAS networking can achieve the max-min throughput globally edge coloring. I leveraged the upper and lower bound to accelerate the optimization of edge coloring. This dissertation paves a way regarding UAS networking in the integration of CPS and machine learning. The UAS networking can achieve outstanding performance in a decentralized architecture. Concurrently, this dissertation gives insights into UAS networking on a large scale. These are fundamental to integrating UAS and National Aerial System (NAS), critical to aviation in the operated and unmanned fields. The dissertation provides novel approaches for the promotion of UAS networking on a large scale. The proposed approaches extend the state-of-the-art of UAS networking in a decentralized architecture. All the alterations can contribute to the establishment of UAS networking with CPS

Resource Allocation in Next Generation Mobile Networks

The increasing heterogeneity of the mobile network infrastructure together with the explosively growing demand for bandwidth-hungry services with diverse quality of service (QoS) requirements leads to a degradation in the performance of traditional networks. To address this issue in next-generation mobile networks (NGMN), various technologies such as software-defined networking (SDN), network function virtualization (NFV), mobile edge/cloud computing (MEC/MCC), non-terrestrial networks (NTN), and edge ML are essential. Towards this direction, an optimal allocation and management of heterogeneous network resources to achieve the required low latency, energy efficiency, high reliability, enhanced coverage and connectivity, etc. is a key challenge to be solved urgently. In this dissertation, we address four critical and challenging resource allocation problems in NGMN and propose efficient solutions to tackle them. In the first part, we address the network slice resource provisioning problem in NGMN for delivering a wide range of services promised by 5G systems and beyond, including enhanced mobile broadband (eMBB), ultra-reliable and low latency (URLLC), and massive machine-type communication (mMTC). Network slicing is one of the major solutions needed to meet the differentiated service requirements of NGMN, under one common network infrastructure. Towards robust mobile network slicing, we propose a novel approach for the end-to-end (E2E) resource allocation in a realistic scenario with uncertainty in slices' demands using stochastic programming. The effectiveness of our proposed methodology is validated through simulations. Despite the significant benefits that network slicing has demonstrated to bring to the management and performance of NGMN, the real-time response required by many emerging delay-sensitive applications, such as autonomous driving, remote health, and smart manufacturing, necessitates the integration of multi-access edge computing (MEC) into network sliding for 5G networks and beyond. To this end, we discuss a novel collaborative cloud-edge-local computation offloading scheme in the next two parts of this dissertation. The first part studies the problem from the perspective of the infrastructure provider and shows the effectiveness of the proposed approach in addressing the rising number of latency-sensitive services and improving energy efficiency which has become a primary concern in NGMN. Moreover, taking into account the perspective of application (higher layer), we propose a novel framework for the optimal reservation of resources by applications, resulting in significant resource savings and reduced cost. The proposed method utilizes application-specific resource coupling relationships modeled using linear regression analysis. We further improve this approach by using Reinforcement Learning to automatically derive resource coupling functions in dynamic environments. Enhanced connectivity and coverage are other key objectives of NGMN. In this regard, unmanned aerial vehicles (UAVs) have been extensively utilized to provide wireless connectivity in rural and under-developed areas, enhance network capacity, and provide support for peaks or unexpected surges in user demand. The popularity of UAVs in such scenarios is mainly owing to their fast deployment, cost-efficiency, and superior communication performance resulting from line-of-sight (LoS)-dominated wireless channels. In the fifth part of this dissertation, we formulate the problem of aerial platform resource allocation and traffic routing in multi-UAV relaying systems wherein UAVs are deployed as flying base stations. Our proposed solution is shown to improve the supported traffic with minimum deployment cost. Moreover, the new breed of intelligent devices and applications such as UAVs, AR/VR, remote health, autonomous vehicles, etc. requires a novel paradigm shift from traditional cloud-based learning to a distributed, low-latency, and reliable ML at the network edge. To this end, Federated Learning (FL) has been proposed as a new learning scheme that enables devices to collaboratively learn a shared model while keeping the training data locally. However, the performance of FL is significantly affected by various security threats such as data and model poisoning attacks. Towards reliable edge learning, in the last part of this dissertation, we propose trust as a metric to measure the trustworthiness of the FL agents and thereby enhance the reliability of FL

A survey of multi-access edge computing in 5G and beyond : fundamentals, technology integration, and state-of-the-art

Driven by the emergence of new compute-intensive applications and the vision of the Internet of Things (IoT), it is foreseen that the emerging 5G network will face an unprecedented increase in traffic volume and computation demands. However, end users mostly have limited storage capacities and finite processing capabilities, thus how to run compute-intensive applications on resource-constrained users has recently become a natural concern. Mobile edge computing (MEC), a key technology in the emerging fifth generation (5G) network, can optimize mobile resources by hosting compute-intensive applications, process large data before sending to the cloud, provide the cloud-computing capabilities within the radio access network (RAN) in close proximity to mobile users, and offer context-aware services with the help of RAN information. Therefore, MEC enables a wide variety of applications, where the real-time response is strictly required, e.g., driverless vehicles, augmented reality, robotics, and immerse media. Indeed, the paradigm shift from 4G to 5G could become a reality with the advent of new technological concepts. The successful realization of MEC in the 5G network is still in its infancy and demands for constant efforts from both academic and industry communities. In this survey, we first provide a holistic overview of MEC technology and its potential use cases and applications. Then, we outline up-to-date researches on the integration of MEC with the new technologies that will be deployed in 5G and beyond. We also summarize testbeds and experimental evaluations, and open source activities, for edge computing. We further summarize lessons learned from state-of-the-art research works as well as discuss challenges and potential future directions for MEC research

Resource management in future mobile networks: from millimetre-wave backhauls to airborne access networks

The next generation of mobile networks will connect vast numbers of devices and support services with diverse requirements. Enabling technologies such as millimetre-wave (mm-wave) backhauling and network slicing allow for increased wireless capacities and logical partitioning of physical deployments, yet introduce a number of challenges. These include among others the precise and rapid allocation of network resources among applications, elucidating the interactions between new mobile networking technology and widely used protocols, and the agile control of mobile infrastructure, to provide users with reliable wireless connectivity in extreme scenarios. This thesis presents several original contributions that address these challenges. In particular, I will first describe the design and evaluation of an airtime allocation and scheduling mechanism devised specifically for mm-wave backhauls, explicitly addressing inter-flow fairness and capturing the unique characteristics of mm-wave communications. Simulation results will demonstrate 5x throughput gains and a 5-fold improvement in fairness over recent mm-wave scheduling solutions. Second, I will introduce a utility optimisation framework targeting virtually sliced mm-wave backhauls that are shared by a number of applications with distinct requirements. Based on this framework, I will present a deep learning solution that can be trained within minutes, following which it computes rate allocations that match those obtained with state-of-the-art global optimisation algorithms. The proposed solution outperforms a baseline greedy approach by up to 62%, in terms of network utility, while running orders of magnitude faster. Third, the thesis investigates the behaviour of the Transport Control Protocol (TCP) in Long-Term Evolution (LTE) networks and discusses the implications of employing Radio Link Control (RLC) acknowledgements under different link qualities, on the performance of transport protocols. Fourth, I will introduce a reinforcement learning approach to optimising the performance of airborne cellular networks serving users in emergency settings, demonstrating rapid convergence (approx. 2.5 hours on a desktop machine) and a 5dB improvement of the median Signal-to-Noise-plus-Interference-Ratio (SINR) perceived by users, over a heuristic based benchmark solution. Finally, the thesis discusses promising future research directions that follow from the results obtained throughout this PhD project