Traditional power grids are currently being transformed into smart grids (SGs). SGs feature multi-way communication among energy generation, transmission, distribution, and usage facilities. The reliable, efficient, and intelligent management of complex power systems requires integration of high-speed, reliable, and secure data information and communication technology into the SGs to monitor and regulate power generation and usage. Despite several challenges, such as trade-offs between wireless coverage and capacity as well as limited spectral resources in SGs, wireless communication is a promising SG communications technology. Cognitive radio networks (CRNs) in particular are highly promising for providing timely SG wireless communications by utilizing all available spectrum resources. We provide in this paper a comprehensive survey on the CRN communication paradigm in SGs, including the system architecture, communication network compositions, applications, and CR-based communication technologies. We highlight potential applications of CR-based SG systems. We survey CR-based spectrum sensing approaches with their major classifications. We also provide a survey on CR-based routing and MAC protocols, and describe interference mitigation schemes. We furthermore present open issues and research challenges faced by CR-based SG networks along with future directions.

Cognitive Radio for Smart Grids: Survey of Architectures, Spectrum Sensing Mechanisms, and Networking Protocols

Machine-to-machine (M2M) communications enables networked devices to exchange information among each other as well as with business application servers and therefore creates what is known as the Internet-of-Things (IoT). The research community has a consensus for the need of a standardized protocol stack for M2M communications. On the other hand, cognitive radio technology is very promising for M2M communications due to a number of factors. It is expected that cognitive M2M communications will be indispensable in order to realize the vision of IoT. However cognitive M2M communications requires a cognitive radio-enabled protocol stack in addition to the fundamental requirements of energy efficiency, reliability, and Internet connectivity. The main objective of this paper is to provide the state of the art in cognitive M2M communications from a protocol stack perspective. This paper covers the emerging standardization efforts and the latest developments on protocols for cognitive M2M networks. In addition, this paper also presents the authors’ recent work in this area, which includes a centralized cognitive medium access control (MAC) protocol, a distributed cognitive MAC protocol, and a specially designed routing protocol for cognitive M2M networks. These protocols explicitly account for the peculiarities of cognitive radio environments. Performance evaluation demonstrates that the proposed protocols not only ensure protection to the primary users (PUs) but also fulfil the utility requirements of the secondary M2M networks.

Cognitive Machine-to-Machine Communications for Internet-of-Things: A Protocol Stack Perspective

The Internet-of-Things (IoT) is the future of the Internet, where everything will be connected. Studies have revealed that fog/edge computing-based services will play a major role in extending the cloud by carrying out intermediary services at the edge of the network. Fog/edge computing-based IoT’s (FECIoT) distributed architecture enhances service provisioning along the Cloud-to-Things continuum, thereby making it suitable for mission-critical applications. Furthermore, the proximity of fog/edge devices to where the data is produced makes it stand-out in terms of resource allocation, service delivery, and privacy. From the business perspective, FECIoT will lead to a boom and spring up of small-to-medium-sized enterprises, thereby encouraging inclusion for all. To this end, we present a comprehensive survey on state-of-the-art IoT literature over the period 2008–2018 and propose the FECIoT framework which covers the enabling technologies, services, and open research issues. A tutorial approach is employed, progressing from basic to more advanced concepts within the IoT domain. Lastly, we show how FECIoT can be deployed in real-life cyber-physical systems, such as the intelligent transportation system, smart grid, smart health-care, smart homes, and smart environment.

Fog/Edge Computing-Based IoT (FECIoT): Architecture, Applications, and Research Issues

The recent bloom of Internet of Things (IoT) and its prevalence in many security-sensitive environments made the security of these networks a crucial requirement. Routing in many of IoT networks has been performed using the routing protocol for low power and lossy networks (RPL), due to its energy-efficient mechanisms, secure modes availability, and its adaptivity to work in various environments; hence, RPL security has been the focus of many researchers. This paper presents a comprehensive study of RPL, its known attacks, and the mitigation methods proposed to counter these attacks. We conducted a detailed review of the RPL standard, including a recently proposed modification. Also, we investigated all recently published attacks on RPL and their mitigation methods through the literature. Based on this investigation, and to the best of our knowledge, we introduced a first-of-its-kind classification scheme for the mitigation methods that is based on the techniques used for the mitigation. Furthermore, we thoroughly discussed RPL-based intrusion detection systems (IDSs) and their classifications, highlighting the most recently proposed IDSs.

Routing Attacks and Mitigation Methods for RPL-Based Internet of Things

Time-critical and delay-sensitive multimedia applications require more spectrum and transmission resources. With the provision of cognitive radios (CRs), the underutilized spectrum resources can be exploited to gain more bandwidth for the bandwidth hungry applications (multimedia applications). Cognitive radio networks (CRNs) also have the flexibility to adjust their transmission parameters according to the needs of multimedia services or applications. For this reason, wireless multimedia cognitive radio networks (WMCRNs) have gained much attentions in today’s research domain. In this paper, we present a comprehensive survey of WMCRNs. Various multimedia applications supported by CRNs, and various CR-based wireless networks are surveyed. We highlight the routing and link layer protocols used for WMCRNs. We cover the quality-of-experience design and security requirements for transmitting multimedia content over CRNs. We provide an in-depth study of white space, television white space, and cross-layer designs that have been used for WMCRNs. We also survey the major spectrum sensing approaches used for the communications of bandwidth hungry and time-critical data over CRNs.

Wireless Multimedia Cognitive Radio Networks: A Comprehensive Survey

It is expected that the use of cognitive radio for smart grid communication will be indispensable in near future. Recently, IETF has standardized RPL (routing protocol for low power and lossy networks), which is expected to be the standard routing protocol for majority of applications including advanced metering infrastructure (AMI) networks. Our objective in this paper is to enhance RPL for cognitive radio enabled AMI networks. Our enhanced protocol provides novel modifications to RPL in order to address the routing challenges in cognitive radio environments along with protecting the primary users as well as meeting the utility requirements of secondary network. System level performance evaluation shows the effectiveness of proposed protocol as a viable solution for practical cognitive AMI networks.

CORPL: A Routing Protocol for Cognitive Radio Enabled AMI Networks

It is expected that cognitive Machine-to-Machine (M2M) communication will be indispensable in near future. Moreover, M2M networks must be Internet Protocol (IP) enabled for ubiquitous connectivity. Recently, IETF has standardized RPL (Routing Protocol for Low Power and Lossy Networks), which is expected to be the standard routing protocol for majority of M2M applications. Our objective in this paper is to enhance RPL for cognitive radio enabled M2M networks. Our enhanced protocol provides novel modifications to RPL in order to address the routing challenges in cognitive radio environments along with protecting the primary users as well as meeting the utility requirements of secondary network. The proposed protocol is evaluated through system level simulation studies.

Enhancing RPL for cognitive radio enabled machine-to-machine networks

Model validation is one of the core issues in modeling and simulation, which aims to check whether the model output correctly reflects the output of the corresponding real system. Model validation is also a complicated process, which requires powerful software to achieve its purpose. In this paper, we describe a simulation model validation tool (shortly SMVT) that we developed recently for the validation purpose of complex simulation models. We first talk about the functions and architectural design of SMVT and then employ a missile simulation model to demonstrate the application of SMVT. This tool has so far been widely used in many scenarios. 

Hongjia Su

Papers

CORPL: A Routing Protocol for Cognitive Radio Enabled AMI Networks

Enhancing RPL for cognitive radio enabled machine-to-machine networks

Design and Development of a Simulation Model Validation Tool