Conference Paper

A Balanced Energy Consumption Protocol for Underwater ASNs

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Abstract

Underwater Acoustic Sensor Networks (UASNs) are deemed to facilitate monitoring tasks in aquatic environment. However, battery resource limitation of sensor nodes leads to shorter network lifetime. Also, unbalanced energy consumption which contributes to limited network lifetime needs to be addressed. Therefore, data transmission technique should be designed to overcome energy dissipation and to optimize network lifetime. This paper presents an Efficient and Balanced Energy consumption Technique (EBET) for UASNs. EBET provision solution for the problems of direct transmission energy consumption over long distance. EBET initially establishes communication links between nodes on the basis of optimal distance threshold. The initial energy of sensor nodes is divided into Energy Level Numbers (ELNs) for balanced energy consumption. Then in data transmission phase, appropriate transmission mechanism is chosen on the basis of specified energy level numbers of sensor nodes. The sensor nodes choose data relay type in accordance to the difference in energy level numbers. Long distance direct data transmission is avoided by selecting high ELN node within transmission range. The effectiveness of EBET is validated through simulations.

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... Acoustic signals can propagate through long distance. However some major issues are created in working on acoustic underwater communication that are limited battery power, limited bandwidth, high propagation delay, low frequency, high bit error rate and multi path fading problems [1]. Most of the existing protocols designed for underwater sensor networks are not suitable for aqueous environment as they produces high energy consumption. ...
... The long distance nodes will require high energy consumption whether they are transmitting data using direct transmission or by using multi-hop transmission. Direct transmission is not applicable for nodes that are not in range of sink, hop by hop transmission produces time delay also transmitting data to the sink from a long distance produces more energy consumption which decreases network lifetime and throughput [1]. ...
... The author proposed various techniques in UASNs. In [1] a protocol was designed that uses energy balancing concept using a sink for receiving of data packets from sensor nodes. Sensor nodes select relay nodes on the basis of minimum distance and high energy levels and transmit data to sink. ...
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Underwater Acoustic Sensor Networks are considered to provide efficient monitoring tasks in aquatic environment but due to limited battery resource of sensor nodes, network lifetime collapses. Energy balancing is the major issue in low network lifetime. High energy consumption creates energy holes and ultimately leads to shorter network lifetime. Therefore, energy consumption must be balanced to increase network life time. To overcome these concerns a technique should be designed that minimizes the energy consumption and prolong network lifetime. This paper presents a Dual Sink Efficient and Balanced Energy consumption Technique (DSEBET) for UASNs. DSEBET overcomes the problem of limited network lifetime and high energy consumption over long distance. Dual sinks underwater model is established. DSEBET first establishes links between nodes on the basis of their optimum distance value and then picks relay nodes on the basis of their minimum distance " N j " value for the transmission of data. In the data transmission phase every nodes have equal energy levels numbers (ELNs). Long distance nodes from one sink will share their data to other sink if come in range of sink otherwise they will establish a multi hop path for transmission of data to the respective sink.
... For example, an exhaustive survey of routing protocols for terrestrial WSN was recently presented in [22]. Similarly, various routing approaches [23] to balance energy consumption in underwater WSN have also been proposed recently. To boost routing performance, some approaches [24] used sink mobility. ...
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... In recent years, researchers have discussed and tackled some of the challenging issues. Although extensive research has been done on the issues of the propagation delay [30][31][32], bandwidth utilization [33][34][35], and energy efficiency [36][37][38] (see more related works in [39][40][41][42][43]), few studies have focused on the more fundamental issue of link reliability. As we can imagine, low reliability would lead to frequent data retransmission; then, frequent retransmission will eventually result in longer delay, higher bandwidth consumption, and higher energy consumption. ...
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The Internet of Underwater Things (IoUT) is a novel class of Internet of Things (IoT), and is defined as the network of smart interconnected underwater objects. IoUT is expected to enable various practical applications, such as environmental monitoring, underwater exploration, and disaster prevention. With these applications, IoUT is regarded as one of the potential technologies toward developing smart cities. To support the concept of IoUT, Underwater Wireless Sensor Networks (UWSNs) have emerged as a promising network system. UWSNs are different from the traditional Territorial Wireless Sensor Networks (TWSNs), and have several unique properties, such as long propagation delay, narrow bandwidth, and low reliability. These unique properties would be great challenges for IoUT. In this paper, we provide a comprehensive study of IoUT, and the main contributions of this paper are threefold: (1) we introduce and classify the practical underwater applications that can highlight the importance of IoUT; (2) we point out the differences between UWSNs and traditional TWSNs, and these differences are the main challenges for IoUT; and (3) we investigate and evaluate the channel models, which are the technical core for designing reliable communication protocols on IoUT.
... [15] proposed a Smooth path construction and adjustment for multiple mobile sinks in WSNs formulated a mathematical programming model and developed an algorithm that constructs a smooth path from a given TSP tour.The proposal reduce average delay per packet but distance travelled was increased. [16] introduced a routing technique, to overcome the energy inefciency problem in UASNs. The protocol selects relay node on the basis of distance and the residual energy levels of sensor nodes. ...
... So, the technique improves network lifetime and is best suited for large scale UASNs. It is worth mentioning that this research work is an extended version of our previous work in [14]. ...
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This paper presents two new energy balanced routing protocols for Underwater Acoustic Sensor Networks (UASNs); Efficient and Balanced Energy consumption Technique (EBET) and Enhanced EBET (EEBET). The first proposed protocol avoids direct transmission over long distance to save sufficient amount of energy consumed in the routing process. The second protocol overcomes the deficiencies in both Balanced Transmission Mechanism (BTM) and EBET techniques. EBET selects relay node on the basis of optimal distance threshold which leads to network lifetime prolongation. The initial energy of each sensor node is divided into energy levels for balanced energy consumption. Selection of high energy level node within transmission range avoids long distance direct data transmission. The EEBET incorporates depth threshold to minimize the number of hops between source node and sink while eradicating backward data transmissions. The EBET technique balances energy consumption within successive ring sectors, while, EEBET balances energy consumption of the entire network. In EEBET, optimum number of energy levels are also calculated to further enhance the network lifetime. Effectiveness of the proposed schemes is validated through simulations where these are compared with two existing routing protocols in terms of network lifetime, transmission loss, and throughput. The simulations are conducted under different network radii and varied number of nodes.
... As a result, network throughput and end to end delay is affected by these coverage holes. A solution for direct transmission energy consumption over long distance is proposed [3]. It is divided in two phases, route setup phase and data transmission phase. ...
Conference Paper
Underwater acoustic communications are a hastily growing field of research and engineering, which once were exclusively for military applications are now extending into commercial fields. Underwater Wireless Sensor Networks (UWSNs) appeal the research community, facing challenges as sensor nodes have energy constraint and radio signals are not suitable for underwater wireless communication. This paper explores an Energy Efficient Hybrid Clustering routing protocol (EEHC) for UWSNs, depicted from Depth-Based Energy-Balanced Hybrid (DB-EBH) routing protocol with integrated clustering technique.
... Simulation result validates the performance in terms of energy efficiency, throughput and network lifetime. EBET (Efficient and Balanced Energy consumption technique) is proposed in [8]. In EBET, the initial energy of the sensor nodes are divided into Energy Level Numbers (ELNs) for balance energy consumption. ...
... The technique used in our proposed protocol is similar as used in EBET [18] protocol but with different architecture. In EBET homogeneous sensor nodes deployed in regions formed in circular shape around the underwater sink node. ...
Chapter
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Chapter
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Thesis
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In Underwater Wireless Sensor Networks (UWSNs), developing an energy efficient routing protocol is a challenge due to the peculiar characteristics of UWSNs. In this paper, we therefore propose an energy-efficient routing protocol, called ERP<sup>2</sup>R (Energy-efficient Routing Protocol based on Physical distance and Residual energy). ERP<sup>2</sup>R is based on a novel idea of utilizing the physical distances of the sensor nodes towards the sink node. ERP<sup>2</sup>R also takes into account the residual energy of the sensor nodes in order to extend the network life-time. Sensor nodes make a local decision of packet forwarding according to their physical distance and the residual energy information. Using the ns-2 simulator, we proved that the ERP<sup>2</sup>R protocol performs better than a representative protocol (i.e. DBR) in terms of energy efficiency, end-to-end delay and network lifetime.
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Providing scalable and ecient routing services in underwater sensor net- works (UWSNs) is very challenging due to the unique characteristics of UWSNs. Firstly, UWSNs often employ acoustic channels for communications because radio signals do not work well in water. Compared with radio-frequency channels, acous- tic channels feature much lower bandwidths and several orders of magnitudes longer propagation delays. Secondly, UWSNs usually have very dynamic topology as sen- sors move passively with water currents. Some routing protocols have been proposed to address the challenging problem in UWSNs. However, most of them assume that the full-dimensional location information of all sensor nodes in a network is known in prior through a localization process, which is yet another challenging issue to be solved in UWSNs. In this paper, we propose a depth-based routing (DBR) protocol. DBR does not require full-dimensional location information of sensor nodes. Instead, it needs only local depth information, which can be easily obtained with an inex- pensive depth sensor that can be equipped in every underwater sensor node. A key advantage of our protocol is that it can handle network dynamics eciently with- out the assistance of a localization service. Moreover, our routing protocol can take advantage of a multiple-sink underwater sensor network architecture without intro- ducing extra cost. We conduct extensive simulations. The results show that DBR can achieve very high packet delivery ratios (at least 95%) for dense networks with only small communication cost.
Conference Paper
This implies that certain trade-offs worthwhile for radios may be too costly for acoustic modems. Furthermore, capabilities inherent in acoustic modems (e.g., the possibility of an ultra-low power re- ceive state) may cause solutions that were too expensive for radio to be justifiable in an underwater network. The main contribution of this work is a preliminary evaluation of idle-time power management techniques for underwater sensor net- works. Through an analysis of the energy consumption of various modes for acoustic modems, we show that for sensors that transmit data with a period on the order of minutes to a few hours, idle-time power management techniques that increase the needed transmis- sion time may perform poorly. As an alternative, we investigate the use of a wakeup mode. Wakeup modes for radios are not a new idea, but they have not yet been widely adopted due to the fact that their implementation requires new hardware and this technology may not be mature enough. However, in this paper we argue for the use of wakeup modes in acoustic modems. To this end, we present an evaluation of four protocols via simulation, demonstrating that the use of an ultra-low power wakeup mode consistently results in the greatest energy savings. The rest of this paper is organized as follows. Section 2 presents the characteristics of acoustic modems and presents their impact on idle-time protocols. Section 3 presents our evaluation of these pro- tocols over different network traffic patterns for acoustic modems. Finally, Section 4 presents some conclusions and future directions.
Conference Paper
Path loss of an underwater acoustic communication channel de- pends not only on the transmission distance, but also on the sig- nal frequency. As a result, the useful bandwidth depends on the transmission distance, a feature that distinguishes an underwater acoustic system from a terrestrial radio one. This fact influences the design of an acoustic network: a greater information through- put is available if messages are relayed over multiple short hops instead of being transmitted directly over one long hop. We assesthe bandwidthdependencyon the distanceusing an an- alytical method that takes into account physical models of acoustic propagation loss and ambient noise. A simple, single-path time- invariant model is considered as a first step. To assess the fun- damental bandwidth limitation, we take an information-theoretic approach and define the bandwidth corresponding to optimal sig- nal energy allocation - one that maximizes the channel capacity subject to the constraint that the transmission power is finite. Nu- merical evaluation quantifies the bandwidth and the channel ca- pacity, as well as the transmission power needed to achieve a pre- specified SNR threshold, as functions of distance. These results lead to closed-form approximations, which may become useful tools in the design and analysis of acoustic networks.
Article
Energy is an extremely critical resource for battery-powered wireless sensor networks (WSN), thus making energy-efficient protocol design a key challenging problem. Most of the existing energy-efficient routing protocols always forward packets along the minimum energy path to the sink to merely minimize energy consumption, which causes an unbalanced distribution of residual energy among sensor nodes, and eventually results in a network partition. In this paper, with the help of the concept of potential in physics, we design an Energy-Balanced Routing Protocol (EBRP) by constructing a mixed virtual potential field in terms of depth, energy density, and residual energy. The goal of this basic approach is to force packets to move toward the sink through the dense energy area so as to protect the nodes with relatively low residual energy. To address the routing loop problem emerging in this basic algorithm, enhanced mechanisms are proposed to detect and eliminate loops. The basic algorithm and loop elimination mechanism are first validated through extensive simulation experiments. Finally, the integrated performance of the full potential-based energy-balanced routing algorithm is evaluated through numerous simulations in a random deployed network running event-driven applications, the impact of the parameters on the performance is examined and guidelines for parameter settings are summarized. Our experimental results show that there are significant improvements in energy balance, network lifetime, coverage ratio, and throughput as compared to the commonly used energy-efficient routing algorithm.
Article
Lifetime prolonging is one of the most significant issues in the research on underwater acoustic sensor networks (UASNs). Unbalanced energy consumption influences greatly the network lifetime. First this study discusses a probability-based energy balance (PEB) scheme. The sensor nodes report the data to the sink by single-hop direct transmission (DT) or by multi-hop transmission (MT) under the probabilities. A centralized probabilities finding algorithm (PFA) can find a set of transmission probabilities to better balance the energy consumption. Then, a sub-optimal distance (SOD)-based data transmission scheme is proposed which is a distributed scheme and operates on each sensor node. It optimizes the slice width and selects the relays near the optimum transmission range. Simulations show that the two schemes can save more energy and prolong the network lifetime efficiently. Copyright © 2008 John Wiley & Sons, Ltd.
Conference Paper
Underwater acoustic networks are envisaged to be the enabling technology for oceanographic data collection, pollution monitoring, offshore exploration and tactical surveillance applications. Unique characteristics of underwater acoustic channels such as large propagation delays and high bit error rates pose a challenge to designing reliable and efficient communication protocols. In this paper, we propose an opportunistic acknowledgement scheme suited for Stop and Wait ARQ protocols and demonstrate using simulations that it achieves better latency and energy efficiency than traditional non-opportunistic schemes for both one and two-dimensional multi-hop acoustic channels.
Energy balanced data propagation in wireless sensor networks
  • C Efthymiou
  • S Nikoletseas
  • J Rolim
Efthymiou, C., Nikoletseas, S., and Rolim, J. (2006). Energy balanced data propagation in wireless sensor networks. Wireless Networks, 12(6), 691-707.