# Design and Implementation of a Mixed IoT LPWAN Network Architecture
###### Abstract  
IoT is much more than a large number of objects or customer devices connected to the Internet. IoT offers organizations many more opportunities than they can imagine. According to this, sooner or later they will probably choose to build their own IoT network. In this article, we review the technologies of IoT LPWAN Sigfox and LoRa. It can be considered the most important at present due to its ability to make the smart city possible. We also propose the development, deployment and implementation of a mixed IoT architecture LoRa-Sigfox composed of components based on open hardware and software. The architecture is evaluated in a real environment focused on remote monitoring of water meter devices. IoT architecture; IoT; LPWAN; Smart metering; Smart cities; LoRa; Sigfox Article Design and Implementation of a Mixed IoT LPWAN Network Architecture  
[PERSON], [PERSON], [PERSON] and [PERSON]. At present there are a wide variety of wireless technologies such as WiFi, Bluetooth, 2G/3G/4G, RFID, ZigBee and many others that allow us to deploy an IoT network. However, the suitable technology will be chosen according to the needs of the design, since each technology has its own characteristics and adapts to different applications. Network coverage, energy consumption of devices and transmission bandwidth, are some of the factors to be considered [5]. The connection of such a large number of objects envisages new challenges for the networks supporting them, and must have a high scalability to absorb the expected exponential growth as well as simplicity in the registration of new devices. In this context, the objects must have an optimal consumption so that they can be installed in different places without the need for external power supplies. On the other hand, it is interesting that the signal transmitted by the endpoint can reach long distances without attenuating excessively. Also the network traffic will be based on the sending of small packages of information every certain time so it will not be necessary a large bandwidth. Neither the transmission speed nor the latency of the network will be critical parameters. Most important, it will be just the data arrives, regardless of how fast they do it. Under these premises, the network technology that best adapts to the described requirements is LPWAN (Low Power Wide Area Network) [6]. The LPWAN name includes wide area and low power networks specific for IoT applications. They allow the deployment of a large number of connected objects at a low infrastructure costs. They offer long-range connectivity to cheap, battery-operated devices, which require the transmission of small amounts of data at regular intervals of time over a long lifespan [7]. In this work we rely on two of the most popular LPWAN communication systems for IoT networks, such as Sigfox and LoRa. LoRa from Semtech is similar in performance to Sigfox, but with a spread spectrum (SS) approach. Semtech focuses on chip manufacturing for both sensors and base stations, and its business model is based on allowing companies or individual users to deploy their own networks. In the work presented here, this feature is very interesting because it favours the use of M2M and relay communications in low coverage areas where devices have connectivity problems. The business model is different from Sigfox. The mobile telephony operators promoting LoRa technology, offer IoT as another company service. Sigfox is a French startup that gives its name to technology. It is a solution that seeks compatibility with many module manufacturers adopting a neutral position such as Avnet, Telit, Texas Instrument, etc., and therefore there are more variety of devices compatible with this technology in the market known as Sigfox ready devices. Sigfox acts directly on the market as an operator and can talk directly with end customers, which is an opportunity for integrators and specialists in solutions and services to adopt this technology.