Design, Analysis and Implementation of Energy-efficient Broadcast MAC protocols for Wireless Sensor Networks

Energy efficiency of the MAC protocol is a key design factor for wireless sensor networks (WSNs). Due to the importance of the problem, a number of energy efficient MAC protocols have been developed for WSNs. Preamble-sampling based MAC protocols (e.g., B-MAC and X-MAC) have overheads due to their preambles, and are inefficient at large wakeup intervals. SCP-MAC, a very energy efficient scheduling MAC protocol, minimizes the preamble by combining preamble sampling and scheduling techniques; however, it does not prevent energy loss due to overhearing; in addition, due to its synchronization procedure, it results in increased contention and delay. In this paper, we present an energy efficient MAC protocol for WSNs that avoids overhearing and reduces contention and delay by asynchronously scheduling the wakeup time of neighboring nodes. To validate our design and analysis, we implement the proposed scheme on the MicaZ platform. Experimental results show that AS-MAC considerably reduces energy consumption, packet loss and delay when compared with SCP-MAC.

We propose a pseudo-random asynchronous duty cycle MAC protocol in wireless sensor networks. The proposed protocol adopts a hash function to determine the next wake-up times. As the next wake-up times are known in advance, the sensor nodes do not need to remain active until their intended receivers wake up. Given an end-to-end delay requirement, the proposed protocol significantly decreases energy consumption by reducing the idle listening time.

In monitoring wireless sensor networks (WSNs) with event-driven applications, the generated traffic usually has bursty characteristics when an event occurs. Transient congestion in the networks would increase delay and packet loss rate severely, reducing the network performance greatly. Through the analysis on delay and packet loss rate in congestion, this paper proposes a congestion-aware mac protocol (C-MAC) for wireless sensor networks. In C-MAC, backoff delay of the nodes around contention area is adopted as a congestion indication. In normal state, the CSMA/CA is working well at sensor nodes. And when the congestion occurs, localized TDMA replaces the CSMA/CA in the congestion nodes. With the above mechanism, the congestion nodes only deliver their data during its assigned slots to control the contention overhead. Finally, we implement the C-MAC in our sensor network testbed. The experiment results show that the proposed MAC protocol could effectively operate on the congestion caused by burst information, and reduce both the delay and packet loss rate significantly.

Wireless Sensor Networks use battery-operated computing and sensing devices. It is often impractical or even impossible to charge/replace the exhausted batteries of the nodes. Thus, energy consumption is the main concern in a wireless sensor network. Moreover, a critical event detected by the sensor network should be delivered to the user as soon as possible. Thus, for sensor networks, both energy efficiency and transmission latency are important parameters. In this paper, we propose a novel asynchronous, duty cycled, energy efficient, and low transmission delay for wireless sensor networks, which addresses all the sources of energy waste to make the medium access more energy efficient, while keeping transmission delay low.The currently available asynchronous contention-based MAC protocols require that proper strategies for sender and receiver nodes are provided to rendezvous. However, the proposed protocol does not rely on any rendezvous between sender and receiver. For evaluating the novel MAC protocol, we have simulated this protocol and two very efficient and established MAC protocols, RTS/CTS IEEE 802.11 and S-MAC. The simulation results indicate that the proposed protocol has very good performance. In addition, as the results show, the novel protocol provides a very suitable balance between energy efficiency and transmission delay.

In this paper, we compare two different types of asynchronous MAC protocols for wireless sensor networks (WSNs). The first based on low-power listening (LPL) which uses the transmission of the preamble frame such as (BMAC: Berkeley MAC and XMAC: A Short Preamble MAC) and the subsequent based on beaconing paradigm that uses the transmission of the beacon frame such as (RIMAC: Receiver Initiated MAC). Our experiments are based on the OMNeT++/MiXiM network simulator and implementation details are given in this paper where the energy saving performance is evaluated. The simulation results show that RIMAC saves more energy than XMAC and BMAC while the XMAC is graded second finest ahead of BMAC.

Energy efficiency of MAC protocols in low data rate wireless multimedia sensor networks: A comparative study

The efficient use of energy in wireless sensor networks is critical issue as the battery of a sensor node, in most cases, cannot be recharged or replaced after deployment. In order to detect an event, a sensor node spends most of the time in monitoring its environment, during which a significant amount of energy can be saved by placing the radio in the low power sleep mode when no reception and/or transmission of data is involved. In this paper, we discuss the design of a new MAC protocol for wireless sensor networks whose goal is to extend the lifetime of the network by avoiding major energy waste causes, such as collisions, overhearing and idle listening, without compromising other network performance measures such as network throughput. The performance of the protocol is studied by simulation and is compared to that of the well known S-MAC protocol which is designed to save energy and to the IEEE 802.11 protocol which is designed to maximize throughput.

Due to miniaturization of hardware and availability of low-cost, low-power sensors, Wireless Sensor Network and Multimedia Sensor Network applications are increasing day by day. Each application has a specific quality of service and experience requirements. The design of routing and MAC protocol which can fulfill the requirements of the application is challenging given the constrained nature of these devices. Considerable efforts are directed towards the design of energy efficient QoS-aware routing protocols. In this article, we present state of the art review of routing protocols for Wireless Multimedia Sensor Networks while addressing the challenges and providing insight into research issues.

Naturopathic approaches to weight loss in clinical practice – a mixed methods study

In wireless sensor networks, MAC protocol is used to achieve efficient, fair and balanced allocation of wireless channel resources and access control of nodes in the network, and to control the communication process of nodes in the network. The energy consumption of wireless sensor nodes is mainly concentrated in the communication unit, including: data transceiver, idle listening, protocol control overhead, etc. A good MAC protocol is beneficial to reduce unnecessary energy consumption and enhance node life time. At the same time, MAC protocol, as the bottom protocol of wireless sensor network, provides a stable and reliable communication foundation for the realization of the upper protocol. Therefore, a large number of scholars at home and abroad have carried out extensive and in-depth research on MAC layer protocol of network. In this paper, the research process and progress of MAC layer protocol in wireless sensor networks are analyzed, and the research progress of MAC layer protocol in multi-radio frequency and multi-channel wireless sensor networks is analyzed.

MAC protocols for Wireless Sensor Networks based on channel checking to detect incoming packets (such as Low Power Listening, LPL) require some form of synchronization among sensors, in order to schedule the times in which the sender and the receiver should turn on their radios, and to ensure correct packet delivery. However, while travelling along multihop paths, packets may accumulate delays that force the sensors either to incur packet losses and retransmissions or to readjust the planned scheduling. In both cases this fact impacts on the energy budget of the sensors. In this paper we propose a cross-layer optimization for MAC protocols that use LPL. This optimization takes into account high-level information of the application in order to compute adaptive delays in every sensor along a multihop path, with the goal of adjusting precisely the activity time window of the sensor along the path. We validate our delay-based model by evaluating different scenarios, and we compare it against the LPL model. The simulation results confirm the validity of our approach and demonstrate that a delay-based model can improve the synchronization achieved through the LPL strategy.

Wireless sensor networks congestion occurs easily due to its centralized traffic pattern. Normally, mono-sync wireless sensor network experiences multiple traffic flow congestion in the dense environment of the network, which leads to excess energy consumption and severe packet loss. To overcome these issues, a congestion detection and alleviation mechanism using cluster based heuristic optimized hierarchical routing protocol is proposed in this paper. Here, congestion detection and alleviation utilize the features of sensor nodes. The congestion is categorized into two types: (i) node level congestion and (ii) link level congestion. The node level congestion is detected by assessing the buffer utilization and the interval amid the consecutive data packets. The link level congestion is considered with computing link usage utilizing back-off step of round robin carrier sense multi-access with collision avoidance. Congestion detection and alleviation reactively affected node/link through cuckoo hosted rider search multi-hop routing algorithm. It has two phases: the cluster head selection and multi-path routing. Cluster head selection is performed through Taylor multiple random forest kernel fuzzy C-means clustering algorithm and multi-path routing is performed through cuckoo hosted rider search multi-hop routing algorithm. The simulation of the proposed method is done in network simulator tool. Here, the performance metrics, like packet delivery ratio, delay, energy consumption, packet drop, overhead, network lifetime and throughput are calculated. The experimental outcomes of the proposed technique shows 11.6%, 18.4% and 28.1% lower delay, 78.2%, 65.4% and 52.6% higher packet delivery ratio, and 29.2%, 37.4% and 40.8% lower packet drop compared with the existing methods, like congestion detection and alleviation using multi-attribute decision-making in optimization-based hybrid congestion alleviation routing protocol in wireless sensor networks, congestion detection and alleviation using hybrid K-means with greedy best first search algorithms in packet rate reduction utilizing adaptive weight firefly algorithm ant colony optimization based routing protocol in wireless sensor networks and congestion detection and alleviation using multi-input time on task optimization algorithm for altered gravitational search algorithm routing protocol in wireless sensor networks.

Wireless sensor networks are a promising application of the Internet of Things in the sustainable development of smart cities, and have been afforded significant attention since first being proposed. Authentication protocols aim to protect the security and confidentiality of legitimate users when accessing and transmitting data. However, existing protocols may suffer from one or more security flaws. Recently, Butt et al. proposed an energy-efficient three-factor authentication protocol for wireless sensor networks. However, their protocol is vulnerable to several attacks, and lacks certain security properties. In this paper, the causes of these design flaws are analyzed. Furthermore, we propose a novel three-factor authentication protocol (password, smart card, and biometric information) for wireless sensor networks in Internet of Things contexts. A dynamic anonymous strategy is designed to prevent privacy disclosure and to resist sensor node capture attacks, tracking attacks, and desynchronization attacks. The Find–Guess model and random oracle model are combined to prove the security of the proposed protocol. A comparative analysis with related schemes shows that the proposed protocol has higher security and is able to maintain a low computational overhead.

Performance analysis of an adaptive, energy-efficient MAC protocol for wireless sensor networks

The urban applications of wireless sensor network, such as agriculture and industry occasions, have some unique characteristics which are different from ones of the randomly distributed network. And our paper here focuses on these specific applications and promotes an asynchronous wakeup MAC protocol combined with clustering. We develop a method based on the wakeup as the MAC protocol which permits the nodes sleep most of the time and saves a lot of energy. While at the routing layer, we adopt the clustering idea and divide the whole network into clusters according to the network application structure. Meanwhile, we change the cluster-heads periodically to balance the energy consumption. And through the analysis after, it turns out that the method achieves a good effect when being used in the low traffic network.