## 3 Communication Technologies and Wireless Sensors Networks
### Standards and Protocols
#### 3.2.2 Wireless Protocols
From addressing water pipeline leakage using 4G-powered wireless sensor networks to deploying 5G in smart grids for efficient energy management, these technologies are at the forefront of revolutionizing critical infrastructures. * ZigBee  
ZigBee serves as a wireless network data transmission protocol, supporting mesh and cluster tree architectures. Its functionality, akin to Wi-Fi, distinguishes itself through lower energy consumption, modest bit rates (up to 200 and 50 kbps), and an operational range of about 100 m. ZigBee enables two-way communication, allowing devices to both send and receive signals, with some capable of relaying signals. Developed by the ZigBee Alliance in 2002, this technology boasts collaboration from numerous globally recognized companies, including Samsung, Philips, Siemens, Bosch, Motorola, Amazon, and Xiaomi. The initial ZigBee specification, Version 1.0, emerged in 2004, followed by the introduction of ZigBee 3.0 in 2016. ZigBee networks adopt various topologies. 1. Star topology: primarily utilized in home networks, it features a single coordinator device, with all other end devices communicating directly with it; however, a drawback is the vulnerability of the entire network if the coordinator malfunctions. 2. Tree topology: Comprising a root and its dependent nodes where the coordinator acts as the root and end devices are placed on the last branches. While enabling the connection of more nodes and covering a larger area, this structure introduces transmission delays, and the failure of one node can impact others. 3. Mesh topology: Representing the most intricate network structure, every device can communicate directly with another, either through direct links or intermediaries. This topology is considered superior for ZigBee networks, as it facilitates data continuity by allowing another device to take over if one node fails [45]. The power grid is the heartbeat of modern society, ensuring a continuous and reliable supply of electricity. It powers homes, businesses, hospitals, and essential services. A resilient power grid is vital for economic stability, technological advancement, and the overall well-being of communities, underpinning every facet of our interconnected lives. [PERSON] et al. [46] proposed a prototype design suggested for remote monitoring of power grid components using ZigBee communication. The prototype, tested for various scenarios in a power plant, demonstrated effective data transmission between the remote terminal unit and the monitoring unit through ZigBee wireless technology. Results from three experiments confirmed the prototype's capability to capture dynamic changes in the power grid system over extended periods, even amid frequent minor changes. Another interesting use of ZigBee in critical infrastructures is given in the article of [PERSON]'s [47] research. His article is about a novel application of ZigBee technology for monitoring oil pipelines in critical infrastructures. The proposed hybrid architecture combines ZigBee and LoRa communication at 2.4 GHz, addressing the safety challenges associated with petroleum product transportation. The system involves distinct nodes for monitoring inside and outside the pipeline, using ZigBee for detecting corrosion, fire, leakage, and location. The LoRa protocol facilitates long-range communication of critical parameters to a LoRa-based gateway, which, integrated with Wi-Fi, sends data to a cloud server for remote visualization and analysis, aiding authorities in making informed decisions during emergencies. * NB-IoT  
The Narrowband Internet of Things (NB-IoT) is an emerging IoT technology created by the Third-Generation Partnership Project (3 GPP). Operating alongside LTE in licensed cellular spectrums, NB-IoT aims to establish a low-power wide-area network (LPWAN). Devices utilizing NB-IoT are designed for extended battery life, with an expectancy of up to 10 years on a single battery charge, covering approximately 10 km in range.