The deployment of security services over Wireless Sensor Networks (WSN) and IoT devices brings significant processing and energy consumption overheads. These overheads are mainly determined by algorithmic efficiency, quality of implementation, and operating system. Benchmarks of symmetric primitives exist in the literature for WSN platforms but they are mostly focused on single platforms or single operating systems. Moreover, they are not up to date with respect to implementations and/or operating systems versions which had significant progress. Herein, we provide time and energy benchmarks of reference implementations for different platforms and operating systems and analyze their impact. Moreover, we not only give the first benchmark results of symmetric cryptography for the Intel Edison IoT platform but also describe a methodology of how to measure energy consumption on that platform.

Software-Defined Networking is a promising paradigm for providing flexibility and programmability to computer networks. Our goal is to assess the performance of this paradigm applied to Wireless Sensor Networks. Previous evaluations are not complete, since they study small networks, do not explore crucial performance metrics, or solely examine light traffic conditions. For this, we execute simulations and a testbed experiment. The testbed shows Software-Defined Networking successfully operates in a real network. We study simulated networks up to 289 data-transmitting nodes, while assessing all the main networks metrics: data delivery, delay, control overhead, and energy consumption. We investigate important parameters for Software-Defined Wireless Sensor Networks, such as controller positioning, radio duty cycling, number of data sinks, and use of source routed control messages. The results indicate that Software-Defined Networking is feasible forWireless Sensor Networks, presenting competitive data delivery ratio while saving energy in comparison to RPL, the Routing Protocol for Low-power and lossy networks.

Wireless sensor networks (WSNs) and Internet of Things (IoT) have been used to build several eHealth systems, which enable a physician (or caregiver) to monitor a patient (or elderly) continuously and real time, either locally or remotely, at lower cost and being less intrusive in the routine than the traditional monitoring equipment. Physical therapy aiding systems are a particular case of such systems, with specific characteristics and requirements, concerning equipment, software, and system. This work presents a system aimed at assessing joint angle and vital signs to assist physical therapists. The system is also available to hydrotherapy, which imposes packaging, sensing, and communication challenges. We discuss our design and implementation, as well as common problems with this kind of application. We also present statistical analysis of the system results based on experiments conducted and compared to a goniometer, a standard physical therapy device.

The IEEE 802.15.4 standard is widely used in wireless sensor network applications. While previous work had attempted to model such protocol based on Petri nets, they focused on CSMA/CA, leaving aside the beacon mode implications. Our main contribution is to model the beacon enabled operation mode of the standard, by means of stochastic timed Petri nets. The model was evaluated using the PIPE tool and several metrics, such as throughput, loss rate and number of tries to send a frame, were assessed and compared to NS2 simulations for different scenarios. The results corroborate the model applicability.