Operating System For Wireless Sensor Networks Research Articles

Energy-efficient routing model for water pipeline monitoring based on wireless sensor networks

In wireless sensor networks (WSNs), water pipeline monitoring is one of the domain applications that require lower energy consumption. Sensor nodes have to sense environment parameters and route the leak data to a central node in low power consumption. Several routing techniques have been proposed to enhance the network lifetime in WSNs. In this paper, we propose a heterogeneous two-tiered routing model in low power consumption. Two routing algorithms are applied in each tier of this model. To evaluate the performance capability of the proposed solution, comparison results based on the simulation tool Cooja applied in the WSN operating system Contiki are presented. We detail, also, a new prototyping based on several platforms to validate the proposed approach. This prototype is experienced in a real water pipeline testbed designed for our application.

Mode-oriented hybrid programming of sensor network nodes for supporting rapid and flexible utility assembly

A number of utility programs (utilities for short) have been developed to fulfill application requirements and to assist user operations such as deployment validation and fault diagnosis throughout the lifespan of wireless sensor networks (WSNs). Because these utilities exhibit diverse behaviors and are required to be loaded at various stages, utility integration is a non-trivial task for developers. To support the rapid and flexible assembly of utilities into sensor node firmware, we formulate the utility management problem as a mode-scheduling procedure, in which utilities are grouped into multiple modes and the sensor node switches between modes to run only the corresponding utilities to address application and user needs. The key contribution of this article is a novel mode-oriented programming model, in which code is organized around modes and modules for the clear abstraction of the mode-scheduling procedure. To facilitate utility assembly, the proposed model supports hybrid programming, i.e., simple declarative configuration descriptions can be used to specify the mode-scheduling logic and to load the utility modules implemented with general-purpose imperative languages. To improve system flexibility, the developer’s descriptions are compiled into a compact configuration profile that will be used by a mode scheduler embedded in a WSN operating system to automatically control the mode scheduling. We have developed a Draft platform to support the proposed programming model, including a development environment and WSN middleware implementing the mode scheduler. Our evaluation results show that Draft achieves reduced development complexity and node reconfiguration cost.

The Study of Traffic-Aware ContikiMAC

MAC (Medium Access Control) is an important protocol for wireless sensor networks (WSN) to ensure the efficiency of communication. The ContikiMAC is the default radio duty cycling (RDC) mechanism in Contiki, which is an open source real-time operating system for WSN. ContikiMAC is more energy-efficient than other MAC protocols, but it is not well adapted to variable traffic loads because it’s duty-cycling is based on static wake-up frequency. In this paper, we propose a traffic-aware ContikiMAC which can automatically adjusting the duty cycle according to the traffic load of the network. The simulation results indicate that the traffic-aware ContikiMAC has greatly improved the network in the performance of power consumption, latency and packet loss.

Memory and energy optimization strategies for multithreaded operating system on the resource-constrained wireless sensor node.

Memory and energy optimization strategies are essential for the resource-constrained wireless sensor network (WSN) nodes. In this article, a new memory-optimized and energy-optimized multithreaded WSN operating system (OS) LiveOS is designed and implemented. Memory cost of LiveOS is optimized by using the stack-shifting hybrid scheduling approach. Different from the traditional multithreaded OS in which thread stacks are allocated statically by the pre-reservation, thread stacks in LiveOS are allocated dynamically by using the stack-shifting technique. As a result, memory waste problems caused by the static pre-reservation can be avoided. In addition to the stack-shifting dynamic allocation approach, the hybrid scheduling mechanism which can decrease both the thread scheduling overhead and the thread stack number is also implemented in LiveOS. With these mechanisms, the stack memory cost of LiveOS can be reduced more than 50% if compared to that of a traditional multithreaded OS. Not is memory cost optimized, but also the energy cost is optimized in LiveOS, and this is achieved by using the multi-core “context aware” and multi-core “power-off/wakeup” energy conservation approaches. By using these approaches, energy cost of LiveOS can be reduced more than 30% when compared to the single-core WSN system. Memory and energy optimization strategies in LiveOS not only prolong the lifetime of WSN nodes, but also make the multithreaded OS feasible to run on the memory-constrained WSN nodes.

MIROS: a hybrid real-time energy-efficient operating system for the resource-constrained wireless sensor nodes.

Operating system (OS) technology is significant for the proliferation of the wireless sensor network (WSN). With an outstanding OS; the constrained WSN resources (processor; memory and energy) can be utilized efficiently. Moreover; the user application development can be served soundly. In this article; a new hybrid; real-time; memory-efficient; energy-efficient; user-friendly and fault-tolerant WSN OS MIROS is designed and implemented. MIROS implements the hybrid scheduler and the dynamic memory allocator. Real-time scheduling can thus be achieved with low memory consumption. In addition; it implements a mid-layer software EMIDE (Efficient Mid-layer Software for User-Friendly Application Development Environment) to decouple the WSN application from the low-level system. The application programming process can consequently be simplified and the application reprogramming performance improved. Moreover; it combines both the software and the multi-core hardware techniques to conserve the energy resources; improve the node reliability; as well as achieve a new debugging method. To evaluate the performance of MIROS; it is compared with the other WSN OSes (TinyOS; Contiki; SOS; openWSN and mantisOS) from different OS concerns. The final evaluation results prove that MIROS is suitable to be used even on the tight resource-constrained WSN nodes. It can support the real-time WSN applications. Furthermore; it is energy efficient; user friendly and fault tolerant.

Wireless Sensor Network Operating System Design Rules Based on Real-World Deployment Survey

Wireless sensor networks (WSNs) have been a widely researched field since the beginning of the 21st century. The field is already maturing, and TinyOS has established itself as the de facto standard WSN Operating System (OS). However, the WSN researcher community is still active in building more flexible, efficient and user-friendly WSN operating systems. Often, WSN OS design is based either on practical requirements of a particular research project or research group's needs or on theoretical assumptions spread in the WSN community. The goal of this paper is to propose WSN OS design rules that are based on a thorough survey of 40 WSN deployments. The survey unveils trends of WSN applications and provides empirical substantiation to support widely usable and flexible WSN operating system design.

A new spatial IP assignment method for IP-based wireless sensor networks

Wireless sensor networks (WSNs), one of the commercial wireless mesh networks (WMNs), are envisioned to provide an effective solution for sensor-based AmI (Ambient Intelligence) systems and applications. To enable the communications between AmI sensor networks and the most popular TCP/IP networks seamlessly, the best solution model is to run TCP/IP directly on WSNs (Mulligan et al. 2009; Hui and Culler 2008; Han and Mam 2007; Kim et al. 2007; Xiaohua et al. 2004; Dunkels et al. 2004; Dunkels et al. 2004; Dunkels 2001; Dunkels et al. 2004). In this case, an IP assignment method is required to assign each sensor node a unique IP address. SIPA (Dunkels et al. 2004) is the best known IP assignment method that uses spatial relations and locations of sensor nodes to assign their IP addresses. It has been applied in Contiki (Dunkels et al. 2004), a famous WSN operating system, to support the 6LowPAN protocol. In Chang et al. (2009), we proposed the SLIPA (Scan-Line IP Assignment) algorithm to improve the assignment success rate (ASR) obtained by SIPA. SLIPA can achieve a good ASR when sensor nodes are uniformly distributed. However, if sensor nodes are deployed by other distributions, the improvements would be limited. This paper proposes a new spatial IP assignment method, called SLIPA-Q (SLIPA with equal-quantity partition), to improve SLIPA. Experiments show that, by testing the proposed method 1,000 times with 1,000 randomly deployed sensor nodes, the average ASR obtained by SLIPA-Q is over two times of that obtained by SLIPA. Under the same 88% ASR, the average numbers of sensor nodes those can be successfully assigned by SLIPA-Q, SLIPA, and SIPA are 950, 850, and 135, respectively. Comparing to previous spatial IP assignment methods, SLIPA-Q can achieve dramatic improvements in ASR for assigning IP addresses to a large set of sensor nodes.

Operating Systems for Wireless Sensor Networks: A Survey

This paper presents a survey on the current state-of-the-art in Wireless Sensor Network (WSN) Operating Systems (OSs). In recent years, WSNs have received tremendous attention in the research community, with applications in battlefields, industrial process monitoring, home automation, and environmental monitoring, to name but a few. A WSN is a highly dynamic network because nodes die due to severe environmental conditions and battery power depletion. Furthermore, a WSN is composed of miniaturized motes equipped with scarce resources e.g., limited memory and computational abilities. WSNs invariably operate in an unattended mode and in many scenarios it is impossible to replace sensor motes after deployment, therefore a fundamental objective is to optimize the sensor motes’ life time. These characteristics of WSNs impose additional challenges on OS design for WSN, and consequently, OS design for WSN deviates from traditional OS design. The purpose of this survey is to highlight major concerns pertaining to OS design in WSNs and to point out strengths and weaknesses of contemporary OSs for WSNs, keeping in mind the requirements of emerging WSN applications. The state-of-the-art in operating systems for WSNs has been examined in terms of the OS Architecture, Programming Model, Scheduling, Memory Management and Protection, Communication Protocols, Resource Sharing, Support for Real-Time Applications, and additional features. These features are surveyed for both real-time and non-real-time WSN operating systems.

Link layer driver architecture for unified radio power management in wireless sensor networks

Wireless Sensor Networks (WSNs) represent a new generation of networked embedded systems that must achieve long lifetimes on scarce amounts of energy. Since radio communication accounts for the primary source of power drain in these networks, a large number of different radio power management protocols have been proposed. However, the lack of operating system support for flexibly integrating them with a diverse set of applications and network platforms has made them difficult to use. This article focuses on providing link layer support toward realizing a unified power management architecture (UPMA) for WSNs. In contrast to existing monolithic approaches, we provide (i) a set of standard interfaces that separate link layer power management protocols from common MAC level functionality, (ii) an architectural framework that allows applications to easily swap out different power-management protocols depending on its needs, and (iii) a mechanism for coordinating multiple applications with different power management requirements. We have implemented our approach on both the Mica2 and Telosb radio drivers in TinyOS-2.0, the second generation of the de facto standard operating system for WSNs. Microbenchmark results show that our approach can coordinate the power-management requirements of multiple applications in a platform independent fashion while incurring negligible overhead.

Wireless sensor network operating systems: a survey

The design of operating system for Wireless Sensor Network (WSN) deviates from the traditional operating system design due to their specific characteristics like constrained resources, high dynamics and inaccessible deployment environments. We provide a classification framework that surveys the state of the art in WSN Operating Systems (OS). The purpose of this survey is two-fold, one is to classify the existing operating systems according to important OS features, and the other is to suggest appropriate OSs for different categories of WSN applications, mapping the application requirements and OS features. This classification helps in understanding the contrasting differences among existing operating systems, and lays a foundation to design an ideal WSN OS. We also classified existing WSN applications, to help the application developer in choosing the appropriate OS, based on the application requirements. Summary and analysis, and discussion of future research directions in this area have been presented.