异构无线传感器网络中一种可扩展的代码分发技术

Ongoing advancements in electromechanical, power electronics and wireless communications have made possible the use of wireless sensor networks in remote applications. A wide range of applications such as monitoring of environmental conditions, forest fire protection, disaster management, and target monitoring in military applications utilize these sensor networks to solve problems. This has made wireless sensor networks the hottest topic for research today. These remote and unattended applications require a huge number of sensor nodes working efficiently together for a common goal. Since sensor nodes have limited resources, like processing, power and sensing capacity, these resources need to be used in efficient manner in order to improve a network’s lifetime. One of the most important methods to achieve this is using clusters. Nodes may not have the same energy levels, which makes it even more important for these clusters to work efficiently together to save power. Wireless sensor networks are of homogeneous and heterogeneous type. This paper presents a survey of energy-efficient clustering mechanisms in heterogeneous wireless sensor networks. Nodes in homogeneous wireless sensor networks have similar resources, however heterogeneous networks have nodes with different energy levels that can be effectively used to enhance a network’s lifetime.

Data aggregation processes aim to reduce the amount of exchanged data in wireless sensor networks and consequently minimize the packet overhead and optimize energy efficiency. Securing the data aggregation process is a real challenge since the aggregation nodes must access the relayed data to apply the aggregation functions. The data aggregation security problem has been widely addressed in classical homogeneous wireless sensor networks, however, most of the proposed security protocols cannot guarantee a high level of security since the sensor node resources are limited. Heterogeneous wireless sensor networks have recently emerged as a new wireless sensor network category which expands the sensor nodes’ resources and capabilities. These new kinds of WSNs have opened new research opportunities where security represents a most attractive area. Indeed, robust and high security level algorithms can be used to secure the data aggregation at the heterogeneous aggregation nodes which is impossible in classical homogeneous WSNs. Contrary to the homogeneous sensor networks, the data aggregation security problem is still not sufficiently covered and the proposed data aggregation security protocols are numberless. To address this recent research area, this paper describes the data aggregation security problem in heterogeneous wireless sensor networks and surveys a few proposed security protocols. A classification and evaluation of the existing protocols is also introduced based on the adopted data aggregation security approach.

Efficient code dissemination in wireless sensor networks

Code dissemination is one of the important services of wireless sensor networks (WSNs). Securing the process of code dissemination is essential in some certain WSNs applications, state-of-the-art secure code dissemination protocols for WSNs aim for the efficient source authentication and integrity verification of code image, however, due to the resource constrains of WSNs and the epidemic behavior of the code dissemination system, existing secure code dissemination protocols are vulnerable to Denial of Service (DoS) attacks when sensor nodes can be compromised (insider DoS attacks). In this paper, we identify five different basic types of DoS attacks exploiting the epidemic propagation strategies used by Deluge. They are (1) Higher-version Advertisement attack, (2) False Request attack, (3) Larger-numbered Page attack, (4) Lower-version Adv attack, and (5) Same-version Adv attack. Simulation shows these susceptibilities caused by above insider DoS attacks. Some simple models are also proposed which promote understanding the problem of insider DoS attacks and attempt to quantify the severity of these attacks in the course of code dissemination in WSNs.

Wireless sensor networks are considered ideal candidates for a wide range of applications, such as industry monitoring, data acquisition in hazardous environments, and military operations. It is desirable and sometimes necessary to reprogram sensor nodes through wireless links after deployment, due to, for example, the need of removing bugs and adding new functionalities. The process of propagating a new code image to the nodes in a wireless sensor network is referred to as code dissemination. This paper presents the design, implementation, and evaluation of an efficient, secure, robust, and DoS-resistant code dissemination system named Seluge for wireless sensor networks. Seluge is a secure extension to Deluge, an open source, state-of-the-art code dissemination system for wireless sensor networks. It provides security protections for code dissemination, including the integrity protection of code images and immunity from, to the best of our knowledge, all DoS attacks that exploit code dissemination protocols. Seluge is superior to all previous attempts for secure code dissemination, and is the only solution that seamlessly integrates the security mechanisms and the Deluge efficient propagation strategies. Besides the theoretical analysis that demonstrates the security and performance of Seluge, this paper also reports the experimental evaluation of Seluge in a network of MicaZ motes, which shows the efficiency of Seluge in practice.

Multicast is essential for wireless sensor network (WSN) applications. Existing multicast protocols in WSNs are often designed in a P2P pattern, assuming small number of destination nodes and frequent changes in network topologies. In order to truly adopt multicast in WSNs, we propose a base-station model-based multicast, SenCast, to meet the general requirements of applications. SenCast is scalable and energy-efficient for large group communications in WSNs. Theoretical analysis shows that SenCast is able to approximate the Minimum Nonleaf Nodes (MNN) problem to a ratio of ln ∣R∣ (R is the set of all destinations), the best known lowest bound. We evaluate our design through comprehensive simulations and prototype implementations on Mica2 motes. Experimental results demonstrate that SenCast outperforms previous multicast protocols including the most recent work uCast.

In wireless sensor networks(WSNs) code dissemination is an important technology to remotely add new functionality or fix bugs after the sensors are deployed. As WSNs is usually in hostile environments, secure code dissemination has been a major concern. Most code dissemination protocols are Deluge-based which have to take much energy and memory to deal with the problem caused by out-of-order-delivery of packets in WSNs. Rate less erasure codes based approaches can reduce the overhead. However, none of them can defeat DoS attacks. This paper proposes a novel code dissemination scheme, which integrates immediately authentication into Fountain codes. The analysis shows that propose scheme can provide code image confidentiality, bogus code image protection, DoS protection and out-of-order-delivery-tolerant property.

We develop a new algorithm for spatial field reconstruction in heterogeneous (mixed analog & digital sensors) wireless sensor networks (WSNs). We consider spatial physical phenomena which are observed by a heterogeneous WSN, meaning that it is partially consists of sparsely deployed high-quality sensors and partially of low-quality sensors. The high-quality sensors transmit their (continuous) noisy observations to the Fusion Centre (FC), while the low-quality sensors first perform a simple thresholding operation and then transmit their binary values over imperfect wireless channels to the FC. We develop a novel algorithm that is based on a multivariate series expansion approach resulting in a Saddle-point type approximation. We then present comprehensive study of the performance gain that can be obtained by augmenting the high-quality sensors with low-quality sensors using real data of insurance storm surge database known as the Extreme Wind Storms Catalogue.

Designing and development of energy effective path planning algorithm is very key research domain in order to tackle the issues of limited life-time for Wireless Sensor Networks (WSNs). So in WSNs, energy efficiency is major concern of researchers. Overall advancement in routing protocols prove that clustering is much better approach as compared to flat and location-based energy efficient routing protocols. Due to better performance, multiple energy efficient clustering routing protocols have been proposed. But existing clustering algorithms are centralized or distributed, which are not intelligent enough and do not produce hybrid cluster-head selection. In this paper, we propose a cluster structured path planning algorithm named, Hybrid Advance Distributed Centralized Clustering (HADCC) path planning energy efficient algorithm. HADCC proposed model is fascinated with hybrid cluster head selection algorithm. This hybrid algorithm makes decision of cluster head selection of nodes. In order to execute proposed model we have also proposed an advance network topology, in which the whole network region is divided into two physical levels. First physical level consists of a circular region, containing homogeneous normal nodes and all important Base Station. While, second physical level is outer region of the circle that contains advanced heterogeneous nodes. Simulation results indicate that HADCC prolongs the network lifetime as compared to existing advanced clustering routing protocols for both homogeneous and heterogeneous WSNs. HADCC outperforms in case of stability and network life time as compared to the existing clustering algorithms.

The major problem for most of wireless sensor networks applications is the energy consumption. In this paper we propose a new architecture called EDETA (Energy-efficient aDaptive hiErarchical and robusT Architecture) optimized to save node's power. This architecture is scalable and suitable for heterogeneous and homogeneous wireless sensor networks, supports single or multiple sinks, and also provides features increasely-demanded in the current applications such as fault tolerance and bounded-time response communications. The proposed protocol is able to autoconfigure, and it is based on two-levels hierarchical architecture. The lower level is based on cluster organization, while the upper one is formed as a dynamic tree of clusters heads to send the data to the sink. Our experiments, based on real energy measures, show that EDETA can reduce the energy consumption in typical applications in a factor of 8x compared with most popular power-aware protocols. Furthermore, EDETA multiplies the lifetime of the sensor network while providing, in addition, extra-features such as fault-tolerant mechanisms and bounded time.

Since the emergence of WSNs (Wireless Sensor Networks), various middleware architectures have been proposed to achieve a suitable abstraction from the distribution and management tasks of sensor devices. This allows users to focus on application development. In the near future, WSNs will be more pervasive, common, and distributed. Programming on WSNs requires a novel programming paradigm and middleware, especially in distributed and heterogeneous WSNs. We propose Virtual Sensor Agent-Oriented Middleware (VSAM), a middleware system for distributed and heterogeneous WSNs, which provides data dissemination protocol-independent Application Programming Interface (API) and an integrated platform for sensor applications. VSAM makes it possible to integrate WSNs with traditional networks.

The rapid advancement in computing has enabled the development of low cost wireless sensor networks (WSNs), and making WSNs one of the most important research areas. Based on the characteristics and major purpose of WSNs, it has been proposed to integrate sensor network and database technologies to improve the management of data processed from sensor networks. The distributed database is not a new research issue, but in case of WSN, there exists much extra difficulty because there are numerous constraints in WSNs comparing with traditional distributed database, such as limited energy, mobility and heterogeneity. This paper introduces the basic concept of query processing in WSN and how it is performed, presents the state-of-the-art by examining six current related projects, identifies the research challenges highlighted by major related projects, and looks at how the projects proposed to address those research challenges. It has been found that several limitations of the existing related approaches were emerged in mobile and heterogeneous WSN. This paper has also investigated these limitations and discussed the possible future research directions.

Dissemination and update of the code image plays an important role in application of the Internet of Things (IoT). As a part of the IoT, Wireless sensor networks should provide the code dissemination. The commonly used method for periodical broadcasting metadata packages to determine whether code dissemination is needed consumes excessive energy. So a low energy consumption code dissemination protocol is proposed for this issue. That is whether code dissemination is necessary can be determined when the sensor node is under normal communication. The simulation result shows that the proposal in this article has reduced the energy consumption when the network needs code dissemination.

There are different applications in wireless sensor networks, where sensors with different capacities are deployed. So designing a reliable and scalable routing protocol for a real world wireless heterogeneous sensor network is an interesting task. In this paper, we propose a novel power aware routing for wireless heterogeneous sensor network, which can provide loop less, stateless routing without using any prior neighborhood information. It utilizes both symmetric and asymmetric links to forward a data from source to sink. This protocol explores the neighbor node relations and chooses the best-hop based on node power. It eliminates the low-powered nodes to become hopnodes in the contention process. It also prolongs the network lifetime. Analysis shows that this scheme significantly outperforms the existing protocol in wireless heterogeneous sensor networks.

A Graphical-based educational simulation tool for Wireless Sensor Networks