Heterogeneous Internet of Things (IoT) and multi-access mobile edge computing (MA-MEC) are believed as supporting technologies for building a smart city. The advancement and flourish of IoT are facilitating the entry of human society into the Internet of Everything era, which lay the foundation of the smart city. To address the conflict between computation capability and low-cost mobile devices in IoT, the MA-MEC is available for supporting the resource-limited and computation-sensitive services and applications by computation offloading and distributed content delivery/caching. However, deploying cloud computing capability within the radio access network may face serious security threats, which stem from not only the existing technologies and networks but also the MA-MEC-based IoT itself. Therefore, in this paper, the solutions to address the security threats are investigated from physical layer perspectives, since physical layer security technologies have the advantages of achieving perfect secrecy, low-computational complexity, and resource consumption, and good adaptation for channel changes. Specifically, we investigate the secure wiretap coding, resource allocation, signal processing, and multi-node cooperation, along with physical layer key generation and authentication, to cope with the emerging security challenges. Finally, the paper is concluded with some possible future research directions.
Quantum information processing and quantum communication are novel protocols that originate from the very fundamental and philosophical questions on superposition and entanglement raised since the early days of quantum mechanics. Strikingly, these new protocols offer capabilities beyond communication task possible with classical physics. One very important example is the secure key exchange based on the transmission of individual quantum signals between communication partners. The big vision and frontier in the field of quantum communication research is the development of a Quantum Internet, which establishes entanglement between many different users and devices. Extending today’s internet, the Quantum Internet will readily transfer quantum bits, rather than classical bits, between users near and far and over multiple different channels and could be used for secure communications, quantum computer networks and metrological applications. I will discuss recent advances on implementations and tools useful for generating and distributing photonic quantum entanglement over robust channels including. Time-bin encoding and reference-frame-free protocols. I will also present an overview of the upcoming Canadian quantum communication satellite QEYSSAT.
Entanglement-based quantum links are the backbone of future quantum internet networks, enabling secure communication between distant cities. Realizing such networks requires addressing multiple practical challenges in long-distance quantum key distribution : time synchronisation, interferometer stabilisation and automation. Here, we report several advances. First, we maintained an operational QKD link continuously for 325hours over 50km between two remotes locations, demonstrating the feasibility of long-duration key generation. We further extended secure key distribution up to a 100km operational link connecting the University of Nice to a ground-based optical station, a setup compatible with future quantum satellite connections. Finally, by employing wavelength demultiplexing to separate photons of entangled pairs, we performed QKD across multiple ITU channels, achieving secure key exchange via the BBM92 protocol and time-energy observables.
The quantum internet promises unparalleled capabilities that are provably impossible with the classical internet. However, current quantum networks are often designed with dedicated systems for specified tasks, which hinders the openness and diversity of future quantum internet. To address these limitations, this work proposes a fully heterogeneous quantum network accompanied with several techniques. Our proposal allows users to access the network using any mainstream systems or even partial systems. The network also enables the execution of multiple distinct quantum tasks and provides opportunities for global optimization and cost-efficient design. A five-node quantum network featuring heterogeneous nodes has been implemented, demonstrating the superiority of our proposal through tasks such as quantum key distribution, quantum digital signature, quantum Byzantine agreement, and quantum conference. Notably, the experiment represents the first demonstration of multi-malicious node quantum Byzantine agreement in a quantum network. This work proposed a fully heterogeneous quantum network that connects diverse user systems and enables multiple quantum tasks. A software-defined quantum network structure is also proposed for coordinating network nodes and optimizing network performance. It paves the way for an open and versatile quantum internet.