## 1 Introduction
Usually, Local Area Network (LAN) technologies like IEEE802.11 (WiFi) are used inside buildings, leveraging previously deployed infrastructures. On the other hand, the use of performing wireless technologies, such as WiFi, presents coverage capacity limitations, both in indoor environments (i.e., between different stories of the same building) and in outdoor scenarios (i.e., between different buildings). Last, the use of Power Line Communication (PLC), which makes use of existing electrical infrastructures inside buildings, can be successfully implemented only on the same portion of the electrical network, by thus limiting its application only to very simple user systems. When it comes to more complex systems, such as a campus, a mixed scenario with multiple buildings and external areas is more realistic, leading to consider a Wide Area Network (WAN) approach. In particular, the use of Low Power Wide Area Network (LPWAN) solutions is emerging as a viable option, thanks to their large coverage, low complexity and low power consumption. The use of the LoRaWAN technology could thus represent a very promising solution, due to its good coverage capabilities (both in outdoor and in hybrid environments), whereas its most critical aspect is represented by the relative low data throughput and duty cycle limitation. In addition, the adoption of heterogeneous IoT protocols and devices may present relevant issues, making their large-scale integration cumbersome. Even if the LoRaWAN technology may well fit this kind of application, its main drawback is represented by the limited data throughput, which makes its application questionable. Starting from this remark, in this study we try to answer the following questions:  
* is the LoRaWAN technology able to handle the amount of data and the refresh time intervals required for the monitoring and control of distributed energy resources in a smart campus? * how many devices can be monitored and controlled by a single LoRaWAN gateway? * can the LoRaWAN infrastructure be integrated as complementary solution in an existing monitoring and control architecture? To answer the first question, we analyzed the scientific literature to identify the monitoring and control architectures proposed for the management of distributed energy resources in complex systems. A generalized architecture was thus determined, and then used as reference architecture to determine the refresh time intervals and the type of messages exchanged between the different intelligent devices and the related supervisory entities. Secondly, a proper data model structure was defined to allow the computation of the payload of the communication. It is worth to note that, to the best of the authors' knowledge, the detailed definition of a smart campus use-case, and of the related data model, were never presented in the literature, thus making this contribution part of the novelty of this study. Finally, a proper architecture based on the LoRaWAN class A technology was proposed, and its feasibility was evaluated by verifying its ability of transmitting the required amount of data in the given refresh time intervals. The evaluation is carried out by computing the Time-on-Air duration of monitoring and supervisory control messages. Starting from the results obtained above, we answered the second question by computing the number of devices that can be handled by a single LoRaWAN gateway. The computation has been carried out by considering two different scenarios: a worst case scenario, where each installed device operates with the maximum expected payload, and a realistic scenario, composed by a mixed set of simple sensors and complex devices operating with the expected average uplink and downlink payload. Last, to answer the third question, we proposed an IoT architecture able to transparently manage different communication protocols. The proposed architecture operates only at the application layer, thus not involving the implementation of specific communication techniques.