The Internet of Things (IoT) has changed the worldwide network of people, smart devices, intelligent things, data, and information as an emergent technology. IoT development is still in its early stages, and numerous interrelated challenges must be addressed. IoT is the unifying idea of embedding everything. The Internet of Things offers a huge opportunity to improve the world’s accessibility, integrity, availability, scalability, confidentiality, and interoperability. However, securing the Internet of Things is a difficult issue. The IoT aims to connect almost everything within the framework of a common infrastructure. This helps in controlling devices and, will allow device status to be updated everywhere and at any time. To develop technology via IoT, several critical scientific studies and inquiries have been carried out. However, many obstacles and problems remain to be tackled in order to reach IoT’s maximum potential. These problems and concerns must be taken into consideration in different areas of the IoT, such as implementation in remote areas, threats to the system, development support, social and environmental impacts, etc. This paper reviews the current state of the art in different IoT architectures, with a focus on current technologies, applications, challenges, IoT protocols, and opportunities. As a result, a detailed taxonomy of IoT is presented here which includes interoperability, scalability, security and energy efficiency, among other things. Moreover, the significance of blockchains and big data as well as their analysis in relation to IoT, is discussed. This article aims to help readers and researchers understand the IoT and its applicability to the real world.

Most Internet of Things (IoT) resources are exposed to security risks due to their essential functionality. IoT devices, such as smartphones and tablets, have a limited network, computation, and storage capacity, making them more vulnerable to attacks. In addition, the huge volume of data generated by IoT devices remains an open challenge for existing platforms to process, analyze, and discover underlying trends to create a convenient environment. As a result, to deliver acceptable services, a new solution is necessary to secure data accountability, increase data privacy and accessibility, and extract hidden patterns and usable knowledge. Moving the Internet of Things to a distributed ledger system might be the most effective way to solve these issues. One of the most well-known and extensively utilized distributed ledger systems is the blockchain. Due to its unique properties, such as privacy, accountability, immutability, and anonymity, blockchain technology has recently attracted a lot of interest. Using IoT in conjunction with blockchain technology can bring several benefits. This paper reviews the current state of the art different BIoT architectures, with a focus on current technologies, applications, challenges, and opportunities. The test findings prove that the decentralized authentication platform-based blockchain-based IoT (BIoT) device-to-device architecture has a significantly higher throughput than the gateway-based architecture. To encrypt the elliptical curve cryptographic (ECC) and to generate keys, the Chinese remainder theorem (CRT)-based scheme is proposed and compared with the secure hash algorithm (SHA-256). Finally, ECC-CRT is used to access system performance in terms of latency, throughput, and resource consumption, simulated through the Contiki Cooja (CC) simulator, and alter orderer and peer nodes for performance study in BIoT. A comprehensive analysis and simulation results show that the proposed scheme is secure against a variety of known attacks, including the man-in-the-middle (MiM) attack, and outperforms the SHA-256 cryptographic algorithm. Moreover, the significance of blockchain and IoT, as well as their analysis of proposed architecture, is discussed. This paper will help readers and researchers understand the IoT and its applicability to the real world.

A printed ultrawideband (UWB) monopole antenna with triple‐rectangular band rejection characteristics at WiMAX, WLAN, and satellite band is presented in this paper. The frequency selectivity of each rejection band is improved by employing the mutual coupling of two spiral‐shaped electromagnetic band‐gap (EBG) structures. The proposed design consists of the modified rectangular patch with a compact size of 23.5 × 23 mm² having a partial ground plane and three pairs of spiral EBGs. To mitigate the interference from the WiMAX band, one pair of the spiral is coupled with the microstrip line, which exhibits band rejection of 3.3–3.7 GHz (11.42%). WLAN band from 5.1 to 5.9 GHz (14.5%) is notched by another pair of spiral EBGs designed on the opposite side of the radiating patch, and for satellite band rejection, two spiral EBGs are embedded on the opposite side of the microstrip line which ranges from 7.25 to 7.8 GHz (7.3%). Moreover, peak gain, radiation pattern, and time domain behavior of the proposed design are also investigated in Ansys Electronics Desktop 17.0 to find its suitability in UWB applications.

Aims: This study aimed to propose a routing protocol for IoT-based WBANs that is reliable, power-efficient, and has a high throughput. Background: A variety of services and applications that use wireless connections such as LTE, 3G, Wi-Fi, Bluetooth, and ZigBee communication technologies have become popular in daily life as a result of the rapid development of network hardware technology. Remote medical monitoring and care is one such service. Governments have developed new policies in response to the healthcare needs of aging populations. Their goal is to create a comprehensive medical network based on new wireless technologies like sensor networks and cloud computing. Their purpose is to take the medical industry and the Internet of Things (IoT) to the next level of development. Objective: The goal of our proposed study is to improve the network nodes' ability to stay alive for a longer period of time and to maintain stability. A longer stability period contributes to high packet delivery of the node to the sink that enhances the efficiency of the WBAN network. Methods: The Wireless Body Area Network (WBAN) Internet of Things (IoT) for healthcare applications has attracted attention from various fields of study in the last few years. In this paper, we propose a routing protocol for IoT-based WBANs that is reliable, power-efficient and has a high throughput. To achieve low energy consumption and a longer network lifetime, we used a multi-hop topology. To choose a parent node or forwarder, we propose a cost function that selects a parent node with the highest residual energy and the shortest distance to sink. The residual energy parameter balances energy consumption among sensor nodes, while the distance parameter ensures packet delivery to the sink. Our key goal is to increase WBAN’s total network by raising cumulative energy usage. The residual energy parameter governs the usage of energy by the sensor nodes, while the distance parameter ensures that the packet is effectively transmitted to the sink. Result: Simulation results demonstrate that our proposed protocol is energy efficient and maximizes network stability for longer periods. Conclusion: Real-time health and activity recognition with wearable sensors is a prerequisite for assistive paradigms. In this paper, we suggest a method for routing data to WBANs. The proposed scheme employs a cost function to determine the best route to the sink. The residual energy of nodes and their distance from the sink is used to calculate the cost function. Nodes with a lower cost function value are selected as the parent node. Other nodes are children nodes and send their data to the parent node. The proposed routing scheme improves network stability time and packet delivery to sink, according to our simulation results. Path loss is also investigated in this protocol and will be considered in future work.

As everyone knows the internet of underwater things (IoUT) is an innovative discussion of internet of things (IoT). To help the idea of IoUT, underwater wireless sensor networks (UWSNs) have risen as a promising framework. IoUT is characterized as the system of brilliant consistent submerged items. IoUT is required to empower different functional applications, for example, natural observing, submerged investigation, and fiasco counteractive action. IoUT is viewed as one of the latentinventions toward creating savvy urban communities. The internet of underwater things (IoUT) is characterized as an overall system of savvy interconnected submerged items that empower to screen tremendous unexplored water zones. The motivation behind this chapter is to investigate how to profit by the IoUT to gain from adventure and safeguard the normal submerged assets, and the authors bring up the contrasts among UWSNs and customary territorial wireless sensor networks (TWSNs), and these distinctions are the primary difficulties for IoUT with diverse protocol.