# Design and Implementation of a Mixed IoT LPWAN Network Architecture
###### Abstract
In addition to connecting a large number of objects, the variety of them is also very wide, with many different IoT categories including low-power devices, smart cars, wearables or smart meters. The latter collects user consumed water, gas, or electricity. Other sensors and devices send data from a variety of sources, such as temperature, light, sound, etc. The result of being such a broad term is that we will not find a universal architecture that meets the requirements and needs of each IoT category. An example of reference architecture for Smart meters can be found in [8] which covers multiple aspects such as a cloud architecture that allows monitoring, managing, interacting and processing data from IoT devices. Nevertheless a global reference architecture must also include a network model to communicate devices and have agents and codes for them, as well as the requirements of the products that are capable of supporting this reference architecture [9]. The management of the integral cycle of urban water, from the moment water is collected and arrives at the tap, until it is returned to nature and reused, is divided into three phases: supply, sanitation and reuse. The supply ranges from the collection of water until it reaches the connections and meters of the buildings. The sanitation is in charge of the used water, which leaves the houses, and it is returned respecting the environment. The reuse, which is carried out in some cases, uses water coming from for different users different from human consumption, such as garden irrigation,agriculture or some industrial uses. Water is necessary daily. Although it seems abundant, it is not an unlimited resource, and in particular drinking water is necessary for human life. Without conservation efforts, the water supply may be exhausted. Throughout the cycle there are agents in charge of pricing, to ensure customer service, data statistics and prepare regulations [10]. In this work, we propose the design, implementation and evaluation of a solution specialized in residential water management through the development and connection of smart water meter devices, integrated into a mixed IoT LoRa-Sigfox architecture. This solution will allow us to efficiently manage the water distribution network. Unlike most current remote reading systems, and making use of bi-directional communication, in addition to remote reading, will be possible to act remotely on the customer's equipment interrupting the supply in case of incidents. Smart remote reading thanks to the use of smart meters facilitates greater control over the water consumed and thus savings in water consumption are achieved contributing to the development of the EU water directive [11] and the development of Smart cities in this sector [12]. During the implementation of the proposed solution, it was chosen to develop our own devices with embedded hardware and software. The reason was that commercial products did not have all the required functionality and additionally the following advantages have been achieved: (1) Customization capacity according to the needs of the proposal; (2) Scalability to add new functionalities and (3) Low cost design. Likewise, since it is an open design of both hardware and software, it facilitates the research community to create their own solutions, overcoming the drawbacks of other closed commercial products. The smart IoT meter device developed, unlike similar products, not only performs the remote reading function, it is also capable of carrying out remote control over adjacent devices such as a solenoid valve. It was made using the minimum number of possible components and reduced cost, matching the needs of simplicity and economy. The use of a high-level language interpreted for programming facilitates customization.