Article

Nomenclature of Medium Access Control Protocol over Wireless Sensor Networks

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Abstract

Wireless sensor networks (WSNs) are considered as the appealing research area. WSNs require highly robust medium access control (MAC) protocol to enhance the performance in several application areas such as intrusion detection, target detection, industrial automation, environmental monitoring, surveillance system, medical diagnosing system, tactical system and so on. On other hand, there are several factors that affect the performance of these applications particularly selection of weak MAC protocol. In this paper, we provide performance impairing drivers for MAC protocols, which affect the efficiency and robustness of MAC protocols in WSN applications. We classify MAC protocols into six categories, as compared with previous MAC surveys that only focused on classifying the MAC protocols into two, three or four major categories. In addition, we show the link of each category with another based on their existing features. Furthermore, this survey provides a detailed nomenclature in which protocols are categorized based on synchronous and asynchronous communication. This survey also discuss the possible threats and some existing solutions at MAC layer from 2000-2014. Finally, we identify the future research challenges and raise directions for controlling these challenges.

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... MAC protocols play significant role in WSNs that help the nodes for accessing the communication channel to improve the WSN. The MAC protocols are characterized into several categories: contention-based, Scheduled-based, hybrid MAC, cross layer, mobility aware, and real-time [3][4]. Each protocol has specific features that are compatible with different types of application [5]. ...
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Thesis
Energy constraint is known as a main challenge in wireless sensor networks. Obviously, energy efficiency is achieved under applying many different policies. Some of these policies are directly related to the network layers' strategies and the rest of them are indirectly effective on the network performance and their impacts are seen in cross-layer approaches. In this research, we are going to obtain energy efficiency by using the routing enhancement as a direct policy. Generally, routing was known as efficient packet forwarding, namely, we apply constraints over packet flooding and these constraints finally improve network performance. According to this last phase, we can improve network routing by redesign of the constraints but it doesn't mean that we have to design a new routing protocol. In fact, it is sufficient to vary previous routing schemes. We find changes in routing protocol are occurred by two methods; first method is to apply intrinsic changes in basic routing protocol for redesign of constraints, however, second method includes some general and routing-independent constraints. Our schemes is classified into second type. We apply two approach entitled "Depth Zoning" and "Random Cooperation (a probable mechanism)" to reduce energy consumption than the basic routing protocol in dense applications. In our schemes, energy efficiency is occurred, however, we could hold traffic parameter in a suitable condition. In this work, we also represent an adaptive implementation for one of our approaches. A main point about the proposed schemes is integrity for different types of basic routing protocols. [Thesis in Electrical Engineering, Persian Gulf University, 2015][In Persian]; http://dl.pgu.ac.ir/handle/Hannan/186544
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We consider the node replication attack, which is an application-independent attack unique to wireless sensor networks. The attack makes it possible for an adversary to prepare her own low-cost sensor nodes and induce the network to accept them as legitimate ones. To do so, the adversary only needs to physically capture one node, reveal its secret credentials, replicate the node in large quantity, and deploy these malicious nodes back into the network so as to subvert the network with little effort. Recently, Ko et al. proposed a neighbor-based detection scheme to cope with replication attacks. The scheme features distributed detection and takes node mobility into account. It harnesses the dynamic observations of the neighbors of a claimer node and avoids the protocol iterations typically found in distributed detections. Unfortunately, we show that their proposal is subject to various replication attacks that can circumvent the detection. Moreover, it is even possible for a sophisticated adversary to exploit the protocol to revoke legitimate nodes.
Conference Paper
IEEE 802.15.4 is a new standard uniquely designed for low rate wireless sensor networks(WSNs). It targets low data rate, low power consumption and low cost wireless networking, and offers device level wireless connectivity. In this paper, the general coordinated sleeping algorithm and the traffic-adaptive algorithm are combined in IEEE 802.15.4 MAC protocol to achieve high energy efficiency and high performance at the same time. By observing that the sporadic traffic characteristic of WSNs, we propose the traffic-adaptive IEEE 802.15.4 MAC with coordinated sleeping algorithm. Through the various performance studies, the proposed algorithm shows significant performance improvements in wireless sensor networks.
Conference Paper
We introduce TinySec, the first fully-implemented link layer security architecture for wireless sensor networks. In our design, we leverage recent lessons learned from design vulnerabilities in security protocols for other wireless networks such as 802.11b and GSM. Conventional security protocols tend to be conservative in their security guarantees, typically adding 16--32 bytes of overhead. With small memories, weak processors, limited energy, and 30 byte packets, sensor networks cannot afford this luxury. TinySec addresses these extreme resource constraints with careful design; we explore the tradeoffs among different cryptographic primitives and use the inherent sensor network limitations to our advantage when choosing parameters to find a sweet spot for security, packet overhead, and resource requirements. TinySec is portable to a variety of hardware and radio platforms. Our experimental results on a 36 node distributed sensor network application clearly demonstrate that software based link layer protocols are feasible and efficient, adding less than 10% energy, latency, and bandwidth overhead.
Conference Paper
Wireless sensor networks promise fine-grain monitoring in a wide variety of environments. Many of these environments (e.g., indoor environments or habitats) can be harsh for wireless communication. From a networking perspective, the most basic aspect of wireless communication is the packet delivery performance: the spatio-temporal characteristics of packet loss, and its environmental dependence. These factors will deeply impact the performance of data acquisition from these networks.In this paper, we report on a systematic medium-scale (up to sixty nodes) measurement of packet delivery in three different environments: an indoor office building, a habitat with moderate foliage, and an open parking lot. Our findings have interesting implications for the design and evaluation of routing and medium-access protocols for sensor networks.
Article
Wireless sensor networks will be widely deployed in the near future. While much research has focused on making these networks feasible and useful, security has received little attention. We present a suite of security protocols optimized for sensor networks: SPINS. SPINS has two secure building blocks: SNEP and μTESLA. SNEP includes: data confidentiality, two-party data authentication, and evidence of data freshness. μTESLA provides authenticated broadcast for severely resource-constrained environments. We implemented the above protocols, and show that they are practical even on minimal hardware: the performance of the protocol suite easily matches the data rate of our network. Additionally, we demonstrate that the suite can be used for building higher level protocols.
Conference Paper
The execution of a distributed program generates a large state space which needs to be checked in testing and debugging. Atoms are useful abstractions in reducing the state lattice of a distributed computation; we refer to the reduced lattice as the atomic state lattice. However, general predicates remain difficult to check if they are asserted over all states. This paper presents a formulation to attack this problem involving separation of two different concerns: (a) order/synchronization requirement, and (b) computational dependency among atoms. Order requirement is modeled by the serialization of the global states reached by a synchronized set of atoms. Synchrony among atoms is specified by a synchronization predicate. Computational dependency among synchronized states is modeled by a general predicate. With this modeling assumption, the number of the states where a general predicate needs to be checked will be bounded by the number of atoms executed. Two efficient algorithms for checking a general predicate, in the cases where the synchronization predicate is conjunctive or disjunctive, are presented along with their proof of correctness.
Conference Paper
The low-cost, off-the-shelf hardware components in unshielded sensor-network nodes leave them vulnerable to compromise. With little effort, an adversary may capture nodes, analyze and replicate them, and surreptitiously insert these replicas at strategic locations within the network. Such attacks may have severe consequences; they may allow the adversary to corrupt network data or even disconnect significant parts of the network. Previous node replication detection schemes depend primarily on centralized mechanisms with single points of failure, or on neighborhood voting protocols that fail to detect distributed replications. To address these fundamental limitations, we propose two new algorithms based on emergent properties [17], i.e., properties that arise only through the collective action of multiple nodes. Randomized Multicast distributes node location information to randomly-selected witnesses, exploiting the birthday paradox to detect replicated nodes, while Line-Selected Multicast uses the topology of the network to detect replication. Both algorithms provide globally-aware, distributed node-replica detection, and Line-Selected Multicast displays particularly strong performance characteristics. We show that emergent algorithms represent a promising new approach to sensor network security; moreover, our results naturally extend to other classes of networks in which nodes can be captured, replicated and re-inserted by an adversary.
Conference Paper
Energy conservation is a primary concern in sensor networks. Several MAC protocols have been proposed to address this concern. However, the tradeoff between power consumption and latency has not been thoroughly studied. In this paper, we propose a sensor medium access control protocol with dynamic duty cycle, DSMAC, which achieves a good tradeoff between the two performance metrics without incurring much overhead. Moreover, DSMAC is able to adjust its duty cycle with varying traffic conditions without assuming any prior knowledge of application requirements. Both analytical and simulation results have been presented in this paper.
Conference Paper
This paper focuses on reducing the power consumption of wireless microsensor networks. Therefore, a communication protocol named LEACH (low-energy adaptive clustering hierarchy) is modified. We extend LEACH's stochastic cluster-head selection algorithm by a deterministic component. Depending on the network configuration an increase of network lifetime by about 30% can be accomplished. Furthermore, we present a new approach to define lifetime of microsensor networks using three new metrics FND (First Node Dies), HNA (Half of the Nodes Alive), and LND (Last Node Dies).
Article
Sensor networks offer economically viable solutions for a variety of applications. For example, current implementations monitor factory instrumentation, pollution levels, freeway traffic, and the structural integrity of buildings. Other applications include climate sensing and control in office buildings and home environmental sensing systems for temperature, light, moisture, and motion. Sensor networks are key to the creation of smart spaces, which embed information technology in everyday home and work environments. The miniature wireless sensor nodes, or motes, developed from low-cost off-the-shelf components at the University of California, Berkeley, as part of its smart dust projects, establish a self-organizing sensor network when dispersed into an environment. The privacy and security issues posed by sensor networks represent a rich field of research problems. Improving network hardware and software may address many of the issues, but others will require new supporting technologies.