## 3 Communication Technologies and Wireless Sensors Networks
### Standards and Protocols
#### 3.2.2 Wireless Protocols  
The cellular Internet of Things (IoT) refers to a category of communication technologies and protocols that enable Internet connectivity for a wide range of IoT devices using cellular networks. It allows these IoT devices to transmit and receive data over cellular infrastructures, which include technologies such as 2G, 3G, 4G, and 5G. Cellular IoT technologies encompass various standards and protocols designed for connecting IoT devices via cellular networks. Second-generation technology introduced digital voice encoding, enabling more efficient use of the radio spectrum compared with its analog predecessor. It enabled text messaging (SMS) for the first time, revolutionizing communication. In 1991, the European standard GSM (global system for mobile communications) became a global benchmark for 2G, ensuring interoperability and driving widespread adoption. This technology laid the foundation for mobile data services, paving the way for future generations of cellular networks and the evolution of modern smartphones and mobile data connectivity. The history of 3G cellular technology is a pivotal chapter in the evolution of mobile communication. Emerging in the early 2000s, 3G (or third-generation technology) marked a substantial advancement over its predecessors. It introduced high-speed data transmission, enabling not only voice calls but also video calls and mobile internet access. The rollout of 3G networks fostered the proliferation of mobile data services, leading to the birth of mobile applications, video streaming, and mobile browsing. Notable standards like UMTS (universal mobile telecommunications system) and CDMA2000 played key roles in shaping 3G. This technology laid the foundation for the mobile internet era, revolutionizing how we communicate and access information on our portable devices. Although they offer a lot for their technological development today, by the year 2025, both technologies will have been abolished as they will be considered obsolete. * 4G Cellular (Fourth Generation) Fourth-generation cellular technology was a watershed moment in mobile communication. Launched in the late 2000s, 4G (or fourth-generation technology) represented a remarkable leap forward from its 3G predecessor. It introduced unprecedented data speeds and low latency, ushering in the era of high-definition video streaming and faster mobile internet. The long-term evolution (LTE) standard emerged as a global benchmark for 4G, enabling seamless data connectivity. Fourth-generation technology revolutionized communications, serving as the foundation for the mobile app ecosystem, enabling high-quality voice and video calls, and driving the widespread adoption of smartphones. Its impact extended beyond personal communication, supporting the growth of IoT and the development of smart cities and connected devices. Fourth-generation technology has found applications in WSNs, particularly in scenarios demanding higher data rates and lower latency. In WSNs designed for applications such as real-time environmental monitoring or industrial automation, 4G provides a significant advantage. This is especially critical in situations where rapid response is essential. The paper of [PERSON] [41] discusses a novel approach in addressing the critical issue of water pipeline leakage detection. Water supply networks, as we mentioned, are one of the most common critical infrastructures for sustaining human life and the environment, yet billions of cubic meters of water are lost annually due to leaks. To combat this problem, the authors proposed an innovative system that combines machine learning and WSNs to collect data and utilizes 4G networks for remote data transmission, aiming to efficiently identify water pipeline leaks. Similarly, study [42] addressed the pressing issue of water quality monitoring at the Weija dam of the Greater Accra Region of Ghana. A set of smart water sensors and smart water ion sensor devices from Libelium were strategically placed at the Weija dam intake.