Discovery and Mash-up of Physical Resources through a Web of Things Architecture

The Internet of Things has focused on new systems, the so-called smart things, to integrate the physical world with the virtual world by exploiting the network architecture of the Internet. However, defining applications on top of smart things is mainly reserved to system experts, since it requires a thorough knowledge of hardware platforms and some specific programming languages. Furthermore, a common infrastructure to publish and share resource information is also needed. In this paper, we propose a software architecture that simplifies the visual development and execution of mash-up applications based on smart things, exploiting Internet Web protocols and their ubiquitous availability even on constrained devices. We have developed a distributed architecture that allows to create and control mash-up applications in an easy and scalable way, without specific knowledge on both hardware and programming languages. In addition, we have also defined a centralized public database deployed on the Internet, to manage and share physical resource information. The effectiveness of the proposed framework has been tested through a real use case and experimental results have demonstrated the validity of the whole system

Performance Evaluation of end-to-end security protocols in an Internet of Things

Wireless Sensor Networks are destined to play a fundamental role in the next-generation Internet, which will be characterized by the Machine-to-Machine paradigm, according to which, embedded devices will actively exchange information, thus enabling the development of innovative applications. It will contribute to assert the concept of Internet of Things, where end-to-end security represents a key issue. In such context, it is very important to understand which protocols are able to provide the right level of security without burdening the limited resources of constrained networks. This paper presents a performance comparison between two of the most widely used security protocols: IPSec and DTLS. We provide the analysis of their impact on the resources of embedded devices. For this purpose, we have modified existing implementations of both protocols to make them properly run on our hardware platforms, and we have performed an extensive experimental evaluation study. The achieved results are not a consequence of a classical simulation campaign, but they have been obtained in a real scenario that uses software and hardware typical of the current technological developments. Therefore, they can help network designers to identify the most appropriate secure mechanism for end-to-end IP communications involving constrained devices

A Cross-Layer Approach to Minimize the Energy Consumption in Wireless Sensor Networks

Energy efficiency represents one of the primary challenges in the development of wireless sensor networks (WSNs). Since communication is the most power consuming operation for a node, many current energy-efficient protocols are based on duty cycling mechanisms. However, most of these solutions are expensive from both the computational and the memory resources point of view and; therefore, they result in being hardly implementable on resources constrained devices, such as sensor nodes. This suggests to combine new communication protocols with hardware solutions able to further reduce the nodes' power consumption. In this work, a cross-layer solution, based on the combined use of a duty-cycling protocol and a new kind of active wake-up circuit, is presented and validated by using a test bed approach. The resulting solution significantly reduces idle listening periods by awakening the node only when a communication is detected. Specifically, an MAC scheduler manages the awakenings of a commercial power detector connected to the sensor node, and, if an actual communication is detected, it enables the radio transceiver. The effectiveness of the proposed cross-layer protocol has been thoroughly evaluated by means of tests carried out in an outdoor environment

Performance Evaluation of a Novel Animals Tracking System based on UHF RFID Technology

The adoption of solutions based on Radio Frequency IDentification technology in a wide range of contexts is a matter of fact. In many situations, such as the tracking of small-size living animals, the straightforward use of commercial systems does not ensure adequate performance. Consequently, both the RFID hardware and the software control platform should be tailored for the particular application. In this work, the specific requirements of Near Field Ultra High Frequency RFID reader antennas suitable for small-size animal localization and tracking are identified and a control system in a LabVIEW environment is designed. Afterwards, both hardware and software solutions have been implemented and validated. In particular, an algorithm based on the measured Received Signal Strength Indication, in order to obtain precise localization data, was developed and validated. Finally, the set-up of a first working prototype involving built-in-lab reader antennas has been completed and tested. The achieved results prove the effectiveness of the proposed tracking system

HEC-MAC: A Hybrid Energy-Aware Cross-Layer MAC Protocol for Wireless Sensor Networks

Wireless Sensor Networks are a key element of the Internet of Things since they are one of the most interesting pervasive systems. However, they are battery-powered, so energy efficiency represents one of the primary design challenges to address. This goal can be primarily achieved through an optimization of the communication procedure, which is the most power-consuming component of a WSN node. Nevertheless, the poor resources of the embedded devices usually limit the complexity of protocol solutions, which thus are not sufficient to reach satisfactory results. For this reason, the current trend aims at integrating both hardware and software solutions. In this work, a cross-layer solution, based on the combined use of a duty-cycling MAC protocol and a reconfigurable beam-steering antenna, is presented and validated. It significantly reduces the nodes’ power consumption by exploiting scheduling techniques and directional communications. Specifically, a MAC scheduler manages the activation of the antenna sectors based on information coming from both MAC and network layers. This way, node awakenings occur only when an actual communication has to take place and only the interested antenna sector is activated. The effectiveness of the proposed cross-layer approach has been evaluated through OMNeT++ simulation tool

A Web based Virtual Environment as a connection platform between people and IoT

Smart objects are present in our cities everywhere, thus it is becoming more and more necessary to have a connection platform, not only capable to make those objects talk with each other, but to present the results of their functions also to the citizens/users. Objective of this paper is the definition and development of a model that represents a connection and interaction layer between smart objects and people. In particular, we propose an immersive virtual platform, able to engage end- users and let people be aware of the where, what and how factors: where smart objects are deployed in the city, what functionalities/data they offer, and how those data represent context for the urban areas. To prove this particular model, we developed a prototypical Virtual Environment of Things (VEoT), within an immersive 3D environment in which the user can explore the virtualized urban area and interact with the available smart objects through gestures and affordable VR devices. The VEoT is fed by real-time data produced by a multi-protocol sensing middleware that simplifies the interaction with physical devices through high-level (RESTful) APIs. Paying attention to interconnection of people and things, this prototype will empower final users with engaging tools in order to enhance the fruition of the IoT paradigm

Near Field UHF RFID Antenna System Enabling the Tracking of Small Laboratory Animals

Radio frequency identification (RFID) technology is more and more adopted in a wide range of applicative scenarios. In many cases, such as the tracking of small-size living animals for behaviour analysis purposes, the straightforward use of commercial solutions does not ensure adequate performance. Consequently, both RFID hardware and the control software should be tailored for the particular application. In this work, a novel RFID-based approach enabling an effective localization and tracking of small-sized laboratory animals is proposed. It is mainly based on a UHF Near Field RFID multiantenna system, to be placed under the animals’ cage, and able to rigorously identify the NF RFID tags implanted in laboratory animals (e.g., mice). Once the requirements of the reader antenna have been individuated, the antenna system has been designed and realized. Moreover, an algorithm based on the measured Received Signal Strength Indication (RSSI) aiming at removing potential ambiguities in data captured by the multiantenna system has been developed and integrated. The animal tracking system has been largely tested on phantom mice in order to verify its ability to precisely localize each subject and to reconstruct its path. The achieved and discussed results demonstrate the effectiveness of the proposed tracking system

High Performance RFID tags for item-level Tracing Systems

Radio Frequency Identification is a wireless technology that is going to play a very important role as auto-identification solution for many application scenarios, where item-level traceability and high performance are crucial. Currently, some works suggest the use of passive Ultra High Frequency (UHF) tags but, unfortunately, not all the requirements can be met by general-purpose commercial tags in presence of critical operating conditions (e.g. metals and liquids, misalignment between tag and reader antennas, and multiple reading of tags). In this paper, the main features that a Far Field UHF tag should own in order to work properly in the whole supply chain are presented. A tag satisfying all the individuated requirements has been also realized and validated in a controlled test environment able to simulate the pharmaceutical supply chain. Tests have been focused on the above mentioned critical conditions. The performance of the Enhanced tag, in terms of successful read rate, has been compared with those of some commercial Far Field UHF tags. The experimental results are impressive and clearly demonstrate that ad hoc Far Field UHF tags are able to effectively solve many of the performance degradation problems affecting general purpose tags

Innovative IoT-aware Services for a Smart Museum

Smart cities are a trading topic in both the academic literature and industrial world. The capability to provide the users with added-value services through low-power and low-cost smart objects is very attractive in many fields. Among these, art and culture represent very interesting examples, as the tourism is one of the main driving engines of modern society. In this paper, we propose an IoT-aware architecture to improve the cultural experience of the user, by involving the most important recent innovations in the ICT field. The main components of the proposed architecture are: (i) an indoor localization service based on the Bluetooth Low Energy technology, (ii) a wearable device able to capture and process images related to the user's point of view, (iii) the user's mobile device useful to display customized cultural contents and to share multimedia data in the Cloud, and (iv) a processing center that manage the core of the whole business logic. In particular, it interacts with both wearable and mobile devices, and communicates with the outside world to retrieve contents from the Cloud and to provide services also to external users. The proposal is currently under development and it will be validated in the MUST museum in Lecce

An Energy-Efficient MAC Scheduler based on a Switched-Beam Antenna for Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are receiving an ever increasing attention because they are one of the most important technologies enabling the Internet of Things vision. Since nodes of these networks are battery-powered, energy efficiency represents one of the main design objectives. This goal can be primarily achieved through an optimization of the communication phase, which is the most power consuming operation for a WSN node. However, the limited computational and storage resources of physical devices make the design of complex communication protocols particularly hard, suggesting, on the contrary, to integrate more simple communication protocols with hardware solutions aimed at energy saving. In this work, a new MAC protocol, compatible with the IEEE 802.15.4 standard, and a reconfigurable beam-steering antenna are presented and validated. They significantly reduce the nodes’ power consumption by exploiting scheduling techniques and directional communications. Specifically, both during transmission and receiving phases, the node activates exclusively the antenna sector needed to communicate with the intended neighbour. The designed antenna and the proposed protocol have been thoroughly evaluated by means of simulations and test-beds, which have highlighted their good performance. In particular, the MAC protocol has been implemented on the Contiki Operating System and it was compared with the IEEE 802.15.4 standard solution