COVID-19 pandemic has affected the world in an unexpected manner. The human race is battling against the pandemic while schools, universities, industries, hospitals and governments are seeking new methods and technologies to seamlessly continue their usual operations. In response, this paper presents how 5G and IoT (Internet of Things) related technologies can be efficiently utilized and developed to fight against the COVID-19 pandemic. Several use-cases on how 5G and IoT can be enablers to provide innovative solutions in the areas of telehealth, contact tracing, education, retail and supply chains, e-government/ remote office/ information sharing, smart manufacturing and factory automation, e-tourism and entertainment are presented along with their technical requirements and challenges. It is envisaged that the proposed solutions will be instrumental to facilitate the usual lifestyle, work and other day-to-day activities of humans in the post-pandemic world.

As the world prepares for the advent of 6G networks, quantum technologies are becoming critical enablers of the next generation of communication systems. This survey paper investigates the convergence of quantum technologies and 6G networks, focusing on their applications, opportunities and challenges. We begin with an examination of the motivations for integrating quantum technologies into 6G, investigating the potential to overcome the limits of classical computing and cryptography. We then highlight key research gaps, particularly in quantum communication, quantum computing integration and security enhancement. A comprehensive overview of quantum technologies relevant to 6G, including quantum communication devices, quantum computing paradigms, and hybrid quantum-classical approaches is provided. A particular focus is on the role of quantum technologies in enhancing 6G Radio Access Networks (RAN), 6G core and edge network optimization, and 6G security. The survey paper also explores the application of quantum cryptography with a focus on Quantum Key Distribution (QKD), Quantum Secure Direct Communication (QSDC) and quantum-resistant cryptographic algorithms and assesses their implementation challenges and potential impact on 6G networks. We also discuss the significant challenges associated with integrating quantum technologies into existing communications infrastructures, including issues of technological maturity, standardization, and economic considerations. Finally, we summarize the lessons learned from current research and outline future research directions to guide the ongoing development of quantum-enabled 6G networks.

Emergence of the Energy Internet (EI) demands restructuring of traditional electricity grids to integrate heterogeneous energy sources, distribution network management with grid intelligence and big data management. This paradigm shift is considered to be a breakthrough in the energy industry towards facilitating autonomous and decentralized grid operations while maximizing the utilization of Distributed Generation (DG). Blockchain has been identified as a disruptive technology enabler for the realization of EI to facilitate reliable, self-operated energy delivery. In this paper, we highlight six key directions towards utilizing blockchain capabilities to realize the envisaged EI. We elaborate the challenges in each direction and highlight the role of blockchain in addressing them. Furthermore, we summarize the future research directive in achieving fully autonomous and decentralized electricity distribution networks, which will be known as Energy Internet.

The Sixth-Generation (6G) are already in the horizon, owing to advents of communication technologies towards enabling intelligent applications and services. Federated Learning (FL) is a distributed Artificial Intelligence (AI) technology that underpins 6G communication technologies and applications. Interestingly, FL is also a promising contender to enhance 6G security. This paper presents a comprehensive and up-to-date review of FL-enabled 6G security. The paper explores security threats in FL for 6G, threats in FL for 6G, and threats shared across FL and 6G. Subsequently, how FL can be utilized to strengthen 6G security in the Radio Access Network (RAN), Open RAN (O-RAN), network edge, and network orchestration and core is presented. In addition, FL is for 6G application and service security across various emerging applications, ranging from Connected Autonomous Vehicles (CAVs) to the envisaged metaverse applications. The paper then consolidates lessons learned, projects, and proposes future research directions to establish the role of FL in strengthening 6G security.

Energy blockchain applications are becoming inevitable with the transformation of electricity distribution networks into the decentralized Smart Grid 2.0 architecture. The scalability of the blockchain platform plays a key role in catering to the increasing number of nodes connected due to consumer-turned-prosumers being integrated into the distribution grid in a distributed manner. Hence, this study aims to optimize blockchain utilization for Smart Grid 2.0 applications through a novel consensus mechanism, which eliminates the requirement for performing additional complex computations to mine a new block. The algorithm utilizes the grid monitoring process through the existing smart meters, and thus has been capable of reducing the energy footprint for block mining to a fraction of that of the legacy Proof-of-Work algorithm, and reducing the block creation time by ~<60%. The proposed Power Line Monitoring-based Consensus Mechanism (PLMC) algorithm is validated using the Process Analysis Toolkit (PAT). In addition, data collected while monitoring the network for block mining is utilized for power quality measurement purposes.