Improving the sustainability in agriculture is nowadays an important challenge. The automation of irrigation processes via low-cost sensors can to spread technological advances in a sector very influenced by economical costs. This article presents an auto-calibrated pH sensor able to detect and adjust the imbalances in the pH levels of the nutrient solution used in hydroponic agriculture. The sensor is composed by a pH probe and a set of micropumps that sequentially pour the different liquid solutions to maintain the sensor calibration and the water samples from the channels that contain the nutrient solution. To implement our architecture, we use an auto-calibrated pH sensor connected to a wireless node. Several nodes compose our wireless sensor networks (WSN) to control our greenhouse. The sensors periodically measure the pH level of each hydroponic support and send the information to a data base (DB) which stores and analyzes the data to warn farmers about the measures. The data can then be accessed through a user-friendly, web-based interface that can be accessed through the Internet by using desktop or mobile devices. This paper also shows the design and test bench for both the auto-calibrated pH sensor and the wireless network to check their correct operation.

The Internet of Things is a concept that is increasingly present in our lives. The emergence of intelligent devices has led to a paradigm shift in the way technology interacts with the environment, leading society to a smarter planet. Consequently, new advanced telemetry approaches appear to connect all kinds of devices with each other, with companies, or with other networks, such as the Internet. On the road to an increasingly interconnected world, where critical devices rely on communication networks to provide an essential service, there arises the need to ensure the security and reliability of these protocols and applications. In this paper, we discuss a security‐based approach for MQTT (Message Queue Telemetry Transport), which stands out as a very lightweight and widely used messaging and information exchange protocol for IoT (Internet of Things) devices throughout the world. To that end, we propose the creation of a framework that allows for performing a novel, template‐based fuzzing technique on the MQTT protocol. The first experimental results showed that performance of the fuzzing technique presented here makes it a good candidate for use in network architectures with low processing power sensors, such as Smart Cities. In addition, the use of this fuzzer in widely used applications that implement MQTT has led to the discovery of several new security flaws not hitherto reported, demonstrating its usefulness as a tool for finding security vulnerabilities.

The Internet of vehicles (IoV) provides new opportunities for the coordination of vehicles for enhancing safety and transportation performance. Vehicles can be coordinated for avoiding collisions by communicating their positions when near to each other, in which the information flow is indexed by their geographical positions or the ones in road maps. Vehicles can also be coordinated to ameliorate traffic jams by sharing their locations and destinations. Vehicles can apply optimization algorithms to reduce the overuse of certain streets without excessively enlarging the paths. In this way, traveling time can be reduced. However, IoV also brings security challenges, such as keeping safe from virtual hijacking. In particular, vehicles should detect and isolate the hijacked vehicles ignoring their communications. The current work presents a technique for enhancing security by applying certain prioritization rules, using digital certificates, and applying trust and reputation policies for detecting hijacked vehicles. We tested the proposed approach with a novel agent-based simulator about security in IoT for vehicle-to-vehicle (V2V) communications (ABS-SecIoTV2V). The experiments focused on the scenario of avoidance of collisions with hijacked vehicles misinforming other vehicles. The results showed that the current approach increased the average speed of vehicles with a 64.2% when these are giving way to other vehicles in a crossing by means of IoT.

The main objective of this experience lies on the development of positive learning aptitudes on engineering students. The experience presented in this paper has been carried out with the help of the problem-based learning (PBL) methodology. Solutions of medium-high complexity problems by students make them work on the development of different skills. The teaching model turns into a significant and autonomous learning model where students are conscious of their compromise with this process (learning). The obtained results are a starting point to other authors willing to use active learning methodologies within the framework of engineering degrees. Both lecturers and students involved in the experience have done a positive assessment of the methodology.

This paper presents a secure protocol for spontaneous wireless ad hoc networks which uses an hybrid symmetric/asymmetric scheme and the trust between users in order to exchange the initial data and to exchange the secret keys that will be used to encrypt the data. Trust is based on the first visual contact between users. Our proposal is a complete self-configured secure protocol that is able to create the network and share secure services without any infrastructure. The network allows sharing resources and offering new services among users in a secure environment. The protocol includes all functions needed to operate without any external support. We have designed and developed it in devices with limited resources. Network creation stages are detailed and the communication, protocol messages, and network management are explained. Our proposal has been implemented in order to test the protocol procedure and performance. Finally, we compare the protocol with other spontaneous ad hoc network protocols in order to highlight its features and we provide a security analysis of the system.