877 research outputs found
RIOT OS Paves the Way for Implementation of High-Performance MAC Protocols
Implementing new, high-performance MAC protocols requires real-time features,
to be able to synchronize correctly between different unrelated devices. Such
features are highly desirable for operating wireless sensor networks (WSN) that
are designed to be part of the Internet of Things (IoT). Unfortunately, the
operating systems commonly used in this domain cannot provide such features. On
the other hand, "bare-metal" development sacrifices portability, as well as the
mul-titasking abilities needed to develop the rich applications that are useful
in the domain of the Internet of Things. We describe in this paper how we
helped solving these issues by contributing to the development of a port of
RIOT OS on the MSP430 microcontroller, an architecture widely used in
IoT-enabled motes. RIOT OS offers rich and advanced real-time features,
especially the simultaneous use of as many hardware timers as the underlying
platform (microcontroller) can offer. We then demonstrate the effectiveness of
these features by presenting a new implementation, on RIOT OS, of S-CoSenS, an
efficient MAC protocol that uses very low processing power and energy.Comment: SCITEPRESS. SENSORNETS 2015, Feb 2015, Angers, France.
http://www.scitepress.or
Engine performance characteristics and evaluation of variation in the length of intake plenum
In the engine with multipoint fuel injection system using electronically controlled fuel injectors has an intake manifold in which only the air flows and, the fuel is injected into the intake valve. Since the intake manifolds transport mainly air, the supercharging effects of the variable length intake plenum will be different from carbureted engine. Engine tests have been carried out with the aim of constituting a base study to design a new variable length intake manifold plenum. The objective in this research is to study the engine performance characteristics and to evaluate the effects of the variation in the length of intake plenum. The engine test bed used for experimental work consists of a control panel, a hydraulic dynamometer and measurement instruments to measure the parameters of engine performance characteristics. The control panel is being used to perform administrative and management operating system. Besides that, the hydraulic dynamometer was used to measure the power of an engine by using a cell filled with liquid to increase its load. Thus, measurement instrument is provided in this test to measure the as brake torque, brake power, thermal efficiency and specific fuel consumption. The results showed that the variation in the plenum length causes an improvement on the engine performance characteristics especially on the fuel consumption at high load and low engine speeds which are put forward the system using for urban roads. From this experiment, it will show the behavior of engine performance
802.15.4/ZigBee Analysis and Security: tools for practical exploration of the attack surface
This thesis explores methods and techniques for surveying 802.15.4 and ZigBee wireless networks. The tools developed will aid in reconnaissance attacks against target networks; information gathered during this process will be used to profile a target network and its devices, as well as to pinpoint the geolocation of devices for executing physical attacks against the onboard hardware. Attacks against the PHY and MAC layers of the 802.15.4 standard will be explored as well
Supporting Cyber-Physical Systems with Wireless Sensor Networks: An Outlook of Software and Services
Sensing, communication, computation and control technologies are the essential building blocks of a cyber-physical system (CPS). Wireless sensor networks (WSNs) are a way to support CPS as they provide fine-grained spatial-temporal sensing, communication and computation at a low premium of cost and power. In this article, we explore the fundamental concepts guiding the design and implementation of WSNs. We report the latest developments in WSN software and services for meeting existing requirements and newer demands; particularly in the areas of: operating system, simulator and emulator, programming abstraction, virtualization, IP-based communication and security, time and location, and network monitoring and management. We also reflect on the ongoing
efforts in providing dependable assurances for WSN-driven CPS. Finally, we report on its applicability with a case-study on smart buildings
Traffic analyzer front-end for complex IEEE 802.15.4 applications
The last years have seen a proliferation of the use of wireless communication in different applications. The systems range from simple 2-nodes communication to complex mesh systems capable of covering vast areas. Debugging such systems, especially large mesh networks can be a daunting task. There are few tools that can help. In this paper, we present and discuss the results of a monitoring tool we are developing. The system is modular, based on a deterministic multicore processor. In the proof of concept, each monitoring probe is equipped with several IEEE802.15.4 transceivers, making it possible to monitor several wireless channels at the same time and to implement a mitigation of diversity issues in the monitoring. The transceivers could also be used to generate test frames for the system under test if necessary. The parallel architecture makes it easy to add new modules and to synchronize the sniffers with the most appropriate methods. In this phase of the work, we used DCF77 to synchronize the nodes. The collected data is sent to a common host for analysis with appropriate tools. The results show that the architecture is appropriate and that synchronization should be improved
Cooja TimeLine: A Power Visualizer for Sensor Network Simulation
Power consumption is one of the most important factors
in wireless sensor network research, but most simulators do
not provide support for visualizing the power consumption
of an entire sensor network. This makes it hard to develop,
debug, and understand mechanisms and protocols based on
power-saving mechanisms. We present Cooja TimeLine, an
extension to Contiki’s Cooja network simulator, that visualizes
radio traffic and radio usage of sensor networks. Cooja
TimeLine makes is possible to visually see the behavior of
low-power protocols and mechanisms thereby increasing the
understanding of the behavior of sensor networks. We see
this as an important tool for the field moving forward
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