## 1 Introduction  
The evolutionary trends in communication technologies which brought about inventions which includes the Internet of Things (IoT) and Internet of Everything (IoE) have substantially created new and better living standards for humans and their environments [1; 2]. By enabling efficient communication between varieties of devices, the IoT technologies are playing crucial roles in enhancing human quality of living in a broad spectrum of domains that are not limited to day to day smart applications (smart homes, smart transportation, smart education, smart cities), economy applications (enhancement of productivity in manufacturing plants, mining fields, oil and gas fields), health care applications, and security applications [3; 4; 5; 6; 7]. Arguably the fastest growing field in the history of computing, IoT is constantly bringing radical changes to human lives [8; 9]. It is estimated that about 28 billion machine-to-machine (M2M) and consumer electronic devices are projected to be communicating over short-range radio technologies by 2021. Also, by 2024, IoT applications are expected to accrue a revenue of 4.3 trillion dollars [10]. Varieties of communication approaches and connectivity standards have been deployed in IoT environment. Popular short-range standards such as IEEE 802.15.1 and IEEE 802.15.4 have been widely used but their short communication range have been well publicized as a major limitation especially as various key IoT domains require extensive communication range. As alternatives, cellular networks which allows wide connectivity range have been extensively deployed in various capacities. However, the issue of cost and complexity is a major constraint. Low power wide area networks (LPWAN) have presented a viable option to the various shortcomings of the existing IoT connectivity standards. As one of the most prominent IoT connectivity inventions in recent years, LPWAN is a wireless telecommunication technology with enviable characteristic features which includes long-range coverage, low data rates, low power consumption, and low-cost end devices. Also, they have the capacity to accommodate numerous end devices, long battery life, and adaptation to licensed and unlicensed spectrum, and most of the standards utilize simplified star network topology [10; 11; 12; 13]. The authors in [13] categorized capacity and densification, energy efficient operations, coverage, location identification, security and privacy, cost-effectiveness, traffic characteristics etc. as key characteristics and requirements for LPWAN standards. As such, several LPWAN technologies, which include Long Range (LoRa), Random Phase Multiple Access (RPMA), Narrowband Internet of Things (NB-IoT), Sigfox, and Weightless, have been developed and deployed in various capacities. Each LPWAN standard has distinctive operational features which makes them suitable for varieties of tasks and operational environments. However, despite the desirable features that the LPWAN technologies possess, security and privacy concerns have been a major challenge to its wide-range deployment. Due to the heterogeneity, ubiquity, and easy accessibility to devices in the network, LPWAN vulnerabilities to threats and intrusion have continued to rise geometrically [5]. Also, the fact that LPWAN standards mostly deploy simple protocols for bootstrapping and authentication, security and privacy due to their low cost and low energy consumption tags can be ascribed as a major reason for their security vulnerabilities and exploitable threats. Numerous cyberattacks and intrusion menaces in the form of eavesdropping, replay attack, denial of service (DoS) attacks, etc. have been major issues targeting the successful deployment of LPWAN. Major topics such as key management and storage, bootstrapping and authentication have been an area that have continued to be addressed in current research work.