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CoDBR: Cooperative Depth Based Routing for Underwater Wireless Sensor Networks
Abstract
Mission critical applications impose the require-ments of reliability and network efficiency on Underwater Wire-less Sensor Networks (UWSN). Innovative routing solutions are therefore required for efficient data forwarding. In this paper, we propose a cooperative routing scheme for UWSNs to enhance network performance. Many cooperative communication proto-cols are developed investigating physical and MAC layer aspects to improve link efficiency in harsh underwater environment, however, at network layer, it is still largely unexplored. In this paper, Cooperation is employed at network layer in existing non-cooperative routing protocol, Depth Based Routing (DBR), to increase its reliability and throughput. Potential relays are selected on the basis of depth information. Data from source node is cooperatively forwarded to the destination by relay nodes. The simulation results show that CoDBR gives 83% more throughput, 98% more packet acceptance ratio and 90 % less packet drop in the stable region as compared to non-cooperative scheme.
... On the other hand, cooperative routing protocols enhance data reliability, since data are transmitted by sender and relay nodes as well. Many cooperative [15,16], noncooperative [17], and different other types of routing protocols are proposed for UASNs [18,19]. These routing algorithms achieve high reliability at the cost of high latency and excessive energy consumption. ...
... The existing schemes that route data in UASNs do not consider energy awareness, shortest path selection, reliability, and scalability together [15,16]. Instead, the proposed methods generally exploit a single parameter or indicator in the routing of information [20][21][22]. ...
... A cooperative depth-based routing (CoDBR) is presented in [15]. Data are forwarded to the destination using the fixed relaying cooperative technique. ...
In underwater acoustic sensor networks (UASNs), energy awareness, best path selection, reliability, and scalability are among the key factors that decide information delivery to the sea surface. Existing protocols usually do not combine such performance-affecting factors in information routing. As a result, the performance of such protocols usually deteriorates if multiple performance factors are taken into account. To cope with such performance deterioration, this article proposes two routing protocols for UASNs: energy and path-aware reliable routing (EPRR) and cooperative EPRR (Co-EPRR). Compared with the counterpart systems, the proposed protocols have been designed to deal with the problem of long propagation delays and achieve network reliability. The EPRR scheme uses nodes’ physical distance from the surface with its depth, which minimized the delay of packet transmission. The channel interaction time has been reduced, therefore, reducing unwanted channel effects on the data. Furthermore, the density of the nodes in the upper part of the network prevents data loss and limits the rapid death of the nodes. The second proposed scheme, Co-EPRR, uses the concept of routing information from the source to the destination on multiple paths. In Co-EPRR routing, the destination node can receive more than one copy of the data packet. This reduces unfavorable channel effects during data delivery. Both the schemes show good performance in terms of packet delivery ratio, received packet analysis, and end-to-end delay.
... The packets' advancement to target destination is optimized at the cost of high consumed energy and latency, as the involvement of gliders. Hina et al. in [22] propose a scheme in which a sender chooses two optimal relays based on their depth. The scheme is localization free and has high packets advancement towards target destination but suffers from high energy consumption due to redundant packets transfer. ...
... which shows that the destination receives more copies and MRC is used to minimize the probability of error in the data. The calculation of BER follows the same model as described in [22]. ...
... MATLAB is used to perform the simulations. A 3D region of each side of 500 m is considered for the deployment of 225 nodes [22], which is random. The static surface sinks are installed at the surface of the water. ...
Owing to the harsh and unpredictable behavior of the sea channel, network protocols that combat the undesirable and challenging properties of the channel are of critical significance. Protocols addressing such challenges exist in literature. However, these protocols consume an excessive amount of energy due to redundant packets transmission or have computational complexity by being dependent on the geographical positions of nodes. To address these challenges, this article designs two protocols for underwater wireless sensor networks (UWSNs). The first protocol, depth and noise-aware routing (DNAR), incorporates the extent of link noise in combination with the depth of a node to decide the next information forwarding candidate. However, it sends data over a single link and is, therefore, vulnerable to the harshness of the channel. Therefore, routing in a cooperative fashion is added to it that makes another scheme called cooperative DNAR (Co-DNAR), which uses source-relay-destination triplets in information advancement. This reduces the probability of information corruption that would otherwise be sent over a single source-destination link. Simulations-backed results reveal the superior performance of the proposed schemes over some competitive schemes in consumed energy, packet advancement to destination, and network stability.
... Majority of the cooperative communication mechanisms in UWSNS are designed to address the physical and Medium Access Control (MAC) layers issues; however, the network layer has largely been neglected [24]. The basic purpose of cooperative communication schemes is to improve the reliability and link quality in underwater harsh environment. ...
... Moreover, the reliable data delivery is one of the biggest issues in underwater environment. For this purpose, depth-based routing is suggested for maintaining reliability and throughput [24]. Some cooperative routing schemes use mobile sinks to improve the packet delivery ratio [23], [25]; however, it increases the network cost. ...
... Cooperative Depth Based Routing (CoDBR) scheme is proposed to improve throughput and data reliability [24]. Based on profundity information, relays are chosen. ...
Underwater Wireless Sensor Networks (UWSNs) serve as a proficient source to monitor aquatic environment. However, data communications and information routing within these systems offer many challenges. To ensure sufficient network lifetime, energy efficiency in routing protocols serve as a major concern in UWSNs. This paper presents an energy competent cooperative routing scheme known as Region Based Courier-nodes Mobility with Incremental Cooperative (RBCMIC) routing. The proposed scheme uses broadcast nature of wireless nodes and performs an incremental cooperative routing. A rigorous evaluation and verification of the proposed scheme with current state-of-the-art yield improved energy efficiency, resulting in extended network lifetime. The results show that an overall improvement of 20% is witnessed in energy usage, whereas a notable 89% improvement is achieved in end-to-end delay in comparison to DEADS protocol.
... But, in cooperative algorithms, the stability of the network is smaller than that of the noncooperative algorithms because of the high energy consumption in the cooperative schemes. 17 The routing protocols in Nasir et al. 17 and Yan et al. 18 utilize the depth information of the nodes instead of geographical information. In these protocols, all the traffic from the highest depth nodes comes to the water surface and increases the load on the uppermost nodes and causes the load imbalance on nodes. ...
... But, in cooperative algorithms, the stability of the network is smaller than that of the noncooperative algorithms because of the high energy consumption in the cooperative schemes. 17 The routing protocols in Nasir et al. 17 and Yan et al. 18 utilize the depth information of the nodes instead of geographical information. In these protocols, all the traffic from the highest depth nodes comes to the water surface and increases the load on the uppermost nodes and causes the load imbalance on nodes. ...
... When the uppermost nodes die, holes are created and then the rest of the network becomes less effective because of no path to the sink on the water surface. In Nasir et al., 17 this problem is more critical because its energy consumption rate is greater because of cooperation. Also, nodes with the lowest depth are always selected for data routing, which creates data burden on the nodes near the water surface and makes the nodes die quickly. ...
In underwater wireless sensor networks, stability and reliability of the network are of paramount importance. Stability of the network ensures persistent operation of the network that, in consequence, avoids data loss when nodes consume all the battery power and subject to death. Particularly, nodes bearing a low pressure of water die early in the usual routing approach due to being preferred choices for data routing. Reliability ensures minimization of the adverse channel effects on data packets so that the desired information is easily extracted from these packets. This article proposes two routing protocols for underwater wireless sensor networks: reliable and stability-aware routing and cooperative reliable and stability-aware routing. In reliable and stability-aware routing, energy assignment to a node is made on the basis of its depth. Sensor nodes having the lowest depth are assigned the highest amount of energy. This energy assignment is called the energy grade of a node and five energy grades are formed in the proposed network from top to bottom. The energy grade along with energy residing in a node battery and its depth decide its selection as a forwarder node. The reliable and stability-aware routing uses only a single link to forward packets. Such a link may not be reliable always. To overcome this issue, the cooperative reliable and stability-aware routing is proposed which introduces cooperative routing to reliable and stability-aware routing. Cooperative routing involves the reception of multiple copies of data symbols by destination. This minimizes the adverse channel effects on data packets and makes the information extraction convenient and less cumbersome at the final destination. Unlike the conventional approach, the proposed schemes do not take into account the coordinates of nodes for defining the routing trajectories, which is challenging in underwater medium. Simulation results reveal a better behavior of the proposed protocols than some competitive schemes in terms of providing stability to the network, packet transfer to the ultimate destination, and latency.
... According to the protocol CoDBR introduced in [25], each source node independently selects two relay nodes and a destination node for each one-hop cooperative communication based only on the depth information. Accordingly, the three neighbors of source with the first, second, and third lowest depth are assigned as destination, and two relays respectively. ...
... Similarly, the source chooses the routing relay outside the depth threshold on the bases of a weight factor characterized by SNR, residual energy, and depth. The protocol improves packet delivery ratio and energy consumption as compared to CoDBR [25], and DBR [28]. However, its demerits include an increment of endto-end delay since the relay selection is based the depth threshold. ...
... Meanwhile, the energy consumed by node i to receive the L-bits packet is estimated by equation 25. ...
This paper sought to investigate performance of multi-hop underwater acoustic sensor networks (UW-ASNs) when they deploy cooperative routing algorithms combining the cooperative communication and routing methods. Taking into account energy efficiency, the studied schemes are discriminated by different policies of selecting next hop nodes as well as relay nodes of one-hop cooperative communications such that the transmission energy of routing paths is minimized. In order to take full advantage of broadcast nature in wireless communication, we propose to use a node exploited as a joint relay for two-hop cooperative communication. In addition, the unreliable communication of acoustic channels is addressed by incorporated channel-aware mechanism which updates the links by exploiting packet receptions. On the bases of communication, two cooperative routing protocols are developed. Simulation results show that the network employing the proposed schemes achieves an improved performance in terms of energy efficiency, throughput, and end-toend delay as compared to the related works.
... In CoDBR, this high reliability and improved throughput is achieved at the cost of high end-to-end delay. 2,9 The data gathering-based node coordination (DGNC) scheme 10 focuses on sparsely distributed USNs and a path-controllable autonomous underwater vehicle (AUV), with no time synchronization between the two. The DGNC scheme prolongs the lifetime of a sensor network using the AUV's mobility to achieve the shortest wake-up time in the sensor nodes. ...
... Step 3: If a node has received multiple setup messages from reachable neighbor nodes, this node adaptively selects one of them to reach the sink node and initializes PC and U½Á according to equations (8) and (9). ...
... Advantages and disadvantages of existing schemes.2,3,[8][9][10][11][12][13][14] ...
Underwater sensor networks have recently emerged as a promising networking technique for various underwater applications. However, the acoustic routing of underwater sensor networks in the aquatic environment presents challenges in terms of dynamic structure, high rates of energy consumption, long propagation delay, and narrow bandwidth. Therefore, it is difficult to adapt traditional routing protocols, which are known to be reliable in terrestrial wireless networks. In this study, we focus on the development of novel routing algorithms to tackle acoustic transmission problems in underwater sensor networks. The proposed scheme is based on reinforcement learning and game theory and is designed as a routing game model to provide an effective packet-forwarding mechanism. In particular, our Q-learning game paradigm captures the dynamics of the underwater sensor networks system in a decentralized, distributed manner. The results of a performance simulation analysis show that the proposed scheme can outperform existing schemes while displaying balanced system performance in terms of energy efficiency and underwater sensor networks throughput.
... A cooperative depth based routing (CoDBR) proposed [45] have been proposed for UWSNs to increase network efficiency and throughput. In CoDBR, the realy node selection criteria is based on the depth information of nodes. ...
... After processing the data received from source node, the relays transmit amplified data to its known destination D in phase-II which can be expressed as equations 3.4.4 and 3.4.5 [45], ...
... These independent faded data copies are then combined at n 1 using MRC. After combining the received signals, BER of received data packet is calculated at n 1 as in[45] and compared with the threshold BER T h . ...
In this work, we present two routing protocols for circular underwater wireless sensor networks (UWSNs); circular sparsity-aware energy efficient clustering (CSEEC) and circular depth-based sparsity-aware energy efficient clustering (CDSEEC) with sink mobility. In CSEEC, we divide circular network area into 5 concentric circular regions. We deployed sensor nodes randomly and placed a static sink at the top of the circular underwater network region. We further sub-divided the 5 concentric circles into 10 regions. Then, we identified sparse and dense regions based on the number of nodes in each region. We used cluster based routing approach in dense network regions and introduced sink mobility in least node density region to achieve balanced energy consumption in the network. In CDSEEC, circular network area is divided into upper and lower semi-circles. Sensor nodes are random uniformly deployed in upper and lower semi-circles and a static sink is placed at the surface of the network region. In upper semi-circle, each sensor node send its sensed data to surface sink using depth information of sensor nodes to achieve energy efficiency by selecting forwarder node with minimum depth. In lower semi-circle, we implement cluster based routing approach in high node density regions and used sink mobility in least density network regions to achieve balanced energy consumption. In UWSNs, uneven distribution of sensor nodes and dynamic network topology creates void holes and high collision probability due to channel interference in dense networks. For avoiding void holes and reducing collision probability, we proposed a virtual chain based routing (VCBR) protocol for UWSNs. In VCBR, we build virtual chains between sensor nodes and sinks to avoid void holes. VCBR also minimizes collision probability which is due to channel interference in the network. The proposed VCBR protocol, introduces a mechanism to forward data packet through best suitable virtual chain to manage the energy resources of sensor nodes efficiently during data communication. The shortest virtual chain between source node and destination is calculated based on the location information of sensor nodes. Furthermore, we also exploit cooperative diversity by presenting two routing protocols (i.e., fixed adaptive cooperative virtual chain based routing (FACVCBR) and incremental adaptive cooperative virtual chain based routing (IACVCBR) to achieve data reliability and prolong network lifetime. In FACVCBR, source node broadcasts data to destination and two relays to achieve diversity which results in data reliability. In IACVCBR, retransmission of data packet is done incrementally to improve data reliability and successful delivery of data packets. In proposed FACVCBR and IACVCBR protocols, we introduce adaptive power control mechanism to utilize energy of sensor nodes in an efficient manner. We validate our propositions via simulations. The results verify that our proposed routing protocols outperform baseline protocols in terms of selected performance parameters.
... Hina et.al in [37] propose a new routing method called CoDBR protocol. In this protocol, the source node selects the optimal relay(s) on the basis of their depth information. ...
... We select the Depth Based Routing (DBR) [52], Cooperative Depth Based Routing (CoDBR) [37] and Depth and Noise Aware Routing (DNAR) [53] to compare it with our proposed routing scheme for the performance evaluation. The reason is that these protocols consider the lowest depth for data forwarding and they are also a localization-free routing protocols for the UWSNs just like the proposed scheme. ...
Recently, the underwater wireless sensor networks (UWSNs) have been proposed
for the exploration of the aqueous resources and to obtain information about the aquatic
environment. The noise in UWSNs challenges a successful transmission of packets
from a source to the destination. There are many protocols in the literature that
address noise reduction/avoidance during underwater communication. However,
they require localization information of each node that itself is a challenging issue.
This thesis presents a depth and noise-aware routing (DNAR) protocol for UWSNs,
which considers the minimum channel noise and the lowest depth of the sensor
node in order to send the packets reliably from a sender node to a surface sink. In
the DNAR protocol, more energy is assigned to the sensor nodes that have a depth
level ≤ 150m. Therefore, the nodes which are deployed nearby to a surface sink have
more capability of transmission and will not die quickly. Also, the proposed protocol
selects the forwarder candidate that has the lowest depth and minimum channel
noise at the receiver. The proposed scheme requires no geographical information of
the nodes for data routing. The DNAR protocol is validated by Matlab and compared
with the DBR scheme. The simulation demonstrates that the DNAR has better results
in terms of total energy consumption, packet delivery ratio (PDR), and the network
lifetime.
Additionally, in this thesis, a cooperative depth and noise aware routing for
UWSNs is proposed. As compared to the existing cooperative routing protocols,
the CoDNAR protocol selects the destination node based on both the lowest depth
and lowest channel noise. In CoDNAR, a cooperative diversity technique is used
that combat fading and high noise. A Source node uses two paths that forwards
a data packet to the destination node. The one path is directly from a source to
the destination, while the other one is via the relay node(s) to the destination. The
destination node receives multiple copies that combining it by using a maximal ratio
combining technique (MRC). The CoDNAR has the best performance in data delivery
than counterpart techniques, as validated by Matlab simulation.
... However, the cooperative routing consumes more energy than that of non-cooperative routing, as the maximum number of nodes involved in data delivery. This makes the network stability less than that of noncooperative networks [11]. Several routing schemes [11]-[13] take only the information about nodes' depth into account for data delivery instead of the coordinates of the sensor node. ...
... Secondly, the data packets are advanced form the bottom source node towards the upper surface sink node by following the long transmission path, which increases the latency. Moreover, the CoDBR [11] scheme also selects the best forwarder nodes (relay and destination) by considering the same criteria. The contribution of two relay nodes with destination increases the node contribution during the packet advancement, which also increases the energy consumption. ...
Owning to the vital resources in a harsh and unforeseeable aqueous environment, the network stability and reliability in underwater acoustic wireless sensor networks (UAWSNs) have paramount significance. Stability guarantees the consistent performance of the network node's energy consumption, avoids data loss, packets reception time and network lifetime. The reliability of packet ensures the selection of favorable channel and avoid adverse channel effects, and the vital information is easily obtained from data packets. This paper introduces two new routing schemes for UAWSNs; stable and reliable short-path routing (RSPR) scheme, and cooperative reliable short-path routing (CoRSPR). In RSPR routing, the destination node is selected by considering the weighting function parameters of the highest residual energy, highest SNR, lowest euclidean distance, and least number of neighbor nodes. The scheme reduces the energy consumption due to less number of nodes contribution in the packet advancement process. The RSPR protocol is a non-cooperative technique, where the packets are delivered using a single-path link, which may not be consistently reliable. To cope with this issue, the CoRSPR protocol is proposed, which takes cooperative routing into account, for stable and reliable data delivery. In cooperative routing, the reception of more than one copy of the data packet is involved by the destination node. This reduces the unfavorable channel effects during data delivery. The simulation results show that the proposed schemes achieve better performance in terms of dead nodes, energy left in the battery, packet acceptance ratio, successful receiving of packets at the sink and E-2-E delay. INDEX TERMS Acoustic wireless sensor networks, short-path routing, network reliability, RSPR, CoRSPR.
... × 10 −13 . The variation of sound speed due to internal wave movements is almost equal to the vertical movement of water multiplied by dc dz [27], wherec is the speed of non-turbulent sound and can be calculated from (13). Therefore, we propose an approximation model to estimate the effect of the internal seawater wave on the sound as ...
... In consequence, a model that takes into consideration the effect of the KPV parameters T, S, z, ρ, and w on the sound speed can be obtained by combining the significance of equations (12), (13), and (17) together to get the following formula ...
Underwater is a harsh and dynamic environment. Its physical properties are unsteady in the space-time domain and that complicates the communication process inside the water. Moreover, underwater transmissions suffer from many attenuations and scattering sources due to several environmental noises such as shipping, turbulence, wave dynamics, and the background life of the marine organisms. Therefore, opportunistic and cooperative communications are necessary to compensate for the prompt changes in underwater environments. In this paper, we propose a new opportunistic cooperative transmission scheme for underwater networks that is adaptable for various environmental conditions. The proposed scheme employs the key physical variables of the seawater, e.g. temperature, salinity, density, and waves speed, to indicate the proper relaying scheme jointly with the appropriate modulation method and the transmitting power level that suit the current transmission situations. The paper also proposes a study that demonstrates the effects of these variables on the underwater speed of sound which is the most commonly used carrier for underwater communication and hence affect the transmitted signal intensity. The results show that the proposed opportunistic cooperative transmission scheme provides an efficient compromise between the overall network performance and the energy efficiency at the nodes.
... Cooperative transmission technique is introducing physical layer aspects of Under Water Acoustic Communication (UWAC) which further demonstrate the point-to-point counterparts for superiority of cooperative UWAC. The Underwater Decode and Forward and Underwater Amplify and Forward are two asynchronous cooperative data transmission techniques used for improving performance of network [20]. Co-DBR showed 98% more packet acceptance ratio, 90% less packet drop and 83% more throughput in stable region as compare to noncooperative schemes. ...
... Co-DBR showed 98% more packet acceptance ratio, 90% less packet drop and 83% more throughput in stable region as compare to noncooperative schemes. Because of its less packet drop CoDBR is proved to be more beneficial for critical mission applications [20]. ...
Recent research has seen remarkable advancement in the field of Under Water Sensor Networks (UWSNs). Many different protocols are developed in the recent years in this domain. As these protocols can be categorized in a variety of ways according to the mechanisms and functionalities they follow, hence it becomes important to understand their principal working. In this research we have introduced three analysis methods; Clustering based, Localization based and Cooperation based routing by selecting some recent routing protocols in the field of UWSN and presented a comparative analysis according to the categories in which they lie. This research has been taken theoretically and is qualitative one. Also a detail analysis of their key advantages and flaws are also identified in this research.
... Many cooperative algorithms exist in the literature [18][19][20][21][22][23][24]. Some of the existing cooperative algorithms, such as [25][26][27], are reliable but they compromise on energy, which leads to less stability and reduces the life of the network. In the case of poorly designed network architecture in cooperative algorithms, its stability is further reduced. ...
... Many cooperative algorithms exist in the literature [18][19][20][21][22][23][24]. Some of the existing cooperative algorithms, such as [25][26][27], are reliable but they compromise on energy, which leads to less stability and reduces the life of the network. In the case of poorly designed network architecture in cooperative algorithms, its stability is further reduced. ...
Designing an efficient, reliable, and stable algorithm
for underwater acoustic wireless sensor networks(UA-WSNs).
... To reach the broadcast stage of information, data are communicated via a recognized route. CoDBR attains high dependability and reliability at the expense of high end-to-end interruption [20]. This is a multi-hop-based routing procedure in which energy-stable routing significantly reduces the weight on the sensor nodules to direct/accept information. ...
UWSNs (underwater wireless sensor networks) are essential for doing any type of task underwater. Huge broadcast lag, great error degree, small bandwidth, and restricted energy in Underwater Sensor Networks interest concentration of utmost investigators. In UWSNs, the efficient use of energy is one of the main problems, as the substitution of energy sources in this kind of location is extremely costly. UWSNs are utilized in many fields, like measuring pollution, issuing tsunami cautions, conducting offshore surveys, and strategic tracing. For numerous functions, the efficacy and dependability of network regarding prominent operation, energy preservation, small bit error rate, and decreased interruption are fundamental. Nevertheless, UWSN’s exclusive features like small bandwidth accessibility, large interruptions in broadcast, very vivacious network topology, and extreme possibility of error present numerous problems in the growth of effective and dependable communication procedures. As opposed to current deepness-based routing techniques, we are focusing on CoDBR (Cooperative Depth-based Routing) and CEEDBR (Cooperative Energy Efficient Depth-based Routing) procedures to improve network lifespan, energy efficacy, and amount.
... Other challenges include the environmental characteristics, technical challenges, and design challenges that are discussed in Sections 2.2 and 2.3. Many researchers provide a survey on additional challenges that aided UIoT networks and provided some of the solutions to overcome the challenges in UIoT networks, such as network configuration issues [59,[67][68][69], internal or external damages to devices [59,[70][71][72][73][74][75][76], noise issues [77][78][79][80][81][82][83][84][85][86][87][88], high-cost issues [89][90][91][92][93][94][95][96][97][98][99][100][101][102][103][104], insecure UIoT environment [105][106][107][108][109][110][111][112][113][114][115][116][117][118][119], limited resources [120][121][122][123][124][125][126][127][128][129][130], environmental limitation [131][132][133][134][135][136][137][138][139][140], and transmission loss [141][142][143][144][145][146][147][148][149][150][151][152][153][154][155][156][157], etc. Figure 4 shows the comparison of techniques that have been proposed to solve various UIoT issues vs. battery issues in UIoT networks. Additionally, the result identifies that 14.9% of research focused on solving battery issues in UIoT devices [58]. ...
The underwater internet of things (UIoT) has emerged as a booming technology in today’s digital world due to the enhancement of a wide range of underwater applications concerning ocean exploration, deep-sea monitoring, underwater surveillance, diver network monitoring, location and object tracking, etc. Generally, acoustic, infrared (IR), visible light (VL), radiofrequency (RF), and magnet induction (MI) are used as the medium of communication in order to transfer information among digitally linked underwater devices. However, each communication medium has its advantages and limitations: for example, the acoustic communication medium is suitable for long-range data transmission but has challenges such as narrow bandwidth, long delay, and high cost, etc., and the optical medium is suitable for short-range data transmission but has challenges such as high attenuation, and optical scattering due to water particles, etc. Furthermore, UIoT devices are operated using batteries with limited capacity and high energy consumption; hence, energy consumption is considered as one of the most significant challenges in UIoT networks. Therefore, to support reliable and energy-efficient communication in UIoT networks, it is necessary to adopt robust energy optimization techniques for UIoT networks. Hence, this paper focuses on identifying the various issues concerning energy optimization in the underwater internet of things and state-of-the-art contributions relevant to inducement techniques of energy optimization in the underwater internet of things; that provides a systematic literature review (SLR) on various power-saving and optimization techniques of UIoT networks since 2010, along with core applications, and research gaps. Finally, future directions are proposed based on the analysis of various energy optimization issues and techniques of UIoT networks. This research contributes much to the profit of researchers and developers to build smart, energy-efficient, auto-rechargeable, and battery-less communication systems for UIoT networks
... Let us consider S o be the original signal, S sÀd ,S sÀch and S chÀd are the received signals at destination node and CH node through source node and destination node through CH node respectively, N sÀch ,N sÀd ,N chÀd and G sÀch ,G sÀd ,N chÀd are the channel noises and channel gains existing at source to CH, source to destination and CH to destination respectively. The two independent data's are combined by using a diversity combining technique [44]. The signals at destination and CH node through source node are represented as, ...
Underwater Wireless Sensor Networks (UWSN) has received more attention in exploring promising technologies for scientific data collection of underwater natural resources with maximum link reliability. For effective communication among the sensor nodes, reliable data delivery based routing protocols have been designed to avoid long-distance communication in large network areas. But the network-based protocols suffer from many constraints like limited distance-dependent bandwidth, defective channels and high delay. Furthermore, the supplied batteries have limited power and also data transmission cannot be exploited in the long-distance network areas due to the harsh underwater environment. Therefore, a clustering-based mobility pattern routing protocol is required to link long-distance communication over depth areas with less consumed energy and less delay. This paper proposed an energy-efficient Distributed Node Clustering Mobility Pattern Routing Protocol (DNC-MPRP) to reach the long-distance depth area for data transmission with less energy consumption and avoid inaccurate routing paths using mobility patterns in UWSN. This approach consists of several phases: network initialization, Cluster Head (CH) formation and data transmission. In DNC-MPRP, the network is partitioned into two dense areas for near and far distance communications. Then the network configuration initializes the rectangle mobility pattern which is used to reach the surface sink with less delay. Next, the CH formation initializes the cluster area in the large and common area to maintain energy in the collected member nodes. Lastly, the data transmission is adopted only when the coverage area is in the transmission range of the network field. Simulation result depicts that the DNC-MPRP approach would be evaluated in terms of Energy Consumption (EC), Packet Delivery Ratio (PDR), End to End Delay (E2ED) and Network Lifetime (NL) based on the variation of nodes, different transmission range, mobile sink, data rate and payload data with high PDR of 95%, high NL of 1200 s, low E2ED of 9.5 s and less EC than existing methods.
... twice energy as idle period. In a network system with cooperative communication, the energy consumed by cooperation can be more than three times than ordinary energy loss [10]. Therefore, this paper uses a hierarchical cluster network structure to reduce energy consumption on basis of previous research works of underwater routing. ...
Underwater wireless sensor network (UWSN) is one of the effective methods to acquire ocean observation data, and research on underwater routing technology has become a hot spot. However, the lifetime of UWSN is an important factor affecting the overall performance of routing protocols. Due to the uncertain underwater environment and poor link quality, it will affect data integrity and network survival ability. Cooperative communication is an excellent technique for solving such problems. In this communication, the source node forwards data through a cooperative path to improve network throughput, while the destination node receives data packets that do not contain obvious errors. Therefore, this paper provides a cooperative communication method to solve the packet loss problem and lifetime of UWSN. The underwater-layered routing network structure is adopted to divide the network nodes into clusters for energy balance. Compared with the traditional layered protocol, the cooperative communication can better guarantee the link quality of the underwater channel. The k-means algorithm is also used to cluster nodes, and conditional probability can select cluster heads. During data transmission, relay nodes will amplify the signal and backup the data packets to avoid dropping packets. The proposed protocol is simulated and compared with non-cooperative protocols (LDBR and MLCEE), the results show that the proposed protocol outperformed the other protocols in terms of network lifetime, throughput, energy consumption and end-to-end delay.
... Many cooperative algorithms exist in the literature [18][19][20][21][22][23][24]. Some of the existing cooperative algorithms, such as [25][26][27], are reliable but they compromise on energy, which leads to less stability and reduces the life of the network. In the case of poorly designed network architecture in cooperative algorithms, its stability is further reduced. ...
Designing an efficient, reliable, and stable algorithm for underwater acoustic wireless sensor networks (UA-WSNs) needs immense attention. It is due to their notable and distinctive challenges. To address the difficulties and challenges, the article introduces two algorithms: the multilayer sink (MuLSi) algorithm and its reliable version MuLSi-Co using the cooperation technique. The first algorithm proposes a multilayered network structure instead of a solid single structure and sinks placement at the optimal position, which reduces multiple hops communication. Moreover, the best forwarder selection amongst the nodes based on nodes’ closeness to the sink is a good choice. As a result, it makes the network perform better. Unlike the traditional algorithms, the proposed scheme does not need location information about nodes. However, the MuLSi algorithm does not fulfill the requirement of reliable operation due to a single link. Therefore, the MuLSi-Co algorithm utilizes nodes’collaborative behavior for reliable information. In cooperation, the receiver has multiple copies of the same data. Then, it combines these packets for the purpose of correct data reception. The data forwarding by the relay without any latency eliminates the synchronization problem. Moreover, the overhearing of the data gets rid of duplicate transmissions. The proposed schemes are superior in energy cost and reliable exchanging of data and have more alive and less dead nodes.
... In another research, the authors proposed a cooperative routing scheme CoDBR to enhance the reliability and throughput in DBR [11]. In this schema, two forwarders are selected based on depth criteria. ...
Underwater wireless sensor networks have been
deployed lately to facilitate many applications such as underwater
world surveillance and exploration. It relies mainly on acoustic
waves for carrying the sensed data from underwater nodes to
a surface sink. However, many challenges are faced by such
networks including long propagation delays, low bandwidth, the
difficulty of obtaining exact location, mobility, and sparsity of
deployment. An efficient and simple routing strategy that is based
on depth information is used to tackle the problem of localization.
However, all protocols adopting the classical depth-based routing
don’t work well for sparse underwater wireless sensor networks
and consume high energy in a dense network. To overcome
this, we propose a routing strategy that combines the simplicity
of the depth-based routing technique with the acoustic modem
capability of switching between a discrete set of transmission
power levels. Each level is associated with a range at which
the signal-to-noise ratio (SNR) is above the acoustic receiver
threshold. In our strategy, nodes increment their transmission
power level until at least one forwarder is found within a depth
below the sender depth. Our technique shows that using selective
transmission power with DBR enhances the delivery ratio and
reduces the consumed energy with a slight increase in end-to-end
delays.
... The sensor nodes get data, based on threshold, and send it to sink directly in such case if a sink falls in the transmission range, else send it to a relay node cooperatively. Nasir et al. (2014) introduced a novel depth based cooperative routing protocol as CoDBR, especially for specific tasks. In the protocol the cooperation is implemented on the network layer of the existing DBR, for increasing the throughput and reliability of the network, creating the new version of DBR as CoDBR. ...
The balance energy consumption of nodes is a key factor to prolong network lifetime. A sensor node in Underwater Wireless Sensor Networks (UWSNs), has very limited power battery, therefore, utilizing the power battery in efficient manner is still a challenging task. To enhance network lifetime, we proposed an Energy-Efficient Regional base Cooperative Routing (EERBCR) protocol with sink mobility for UWSNs. In EERBCR, we divided the network field in 12 regions, three by four vertically and horizontally respectively. Total numbers of four mobile sinks are positioned, having equal distance to each other while 100 sensors nodes are deployed randomly. Each mobile sink travels on pre-defined straight path and covers 3 regions. All the sensor nodes are in sleeping mode, until the sink arrives to their region, upon the arrival of sink node to a region, it broadcasts a hello message. All the nodes in that region receive that message and activate themselves. When the sink is about to leave the region, it broadcasts another packet, informing the nodes about its departure so that the nodes go back into sleeping mode. The simulation results show the validity of EERBCR as it performed better than Depth-Based Routing (DBR), Energy Efficient Depth-Based Routing (EEDBR) and depth and energy-aware dominating set (DEADS) protocols.
... However, it does not consider the energy of the remaining nodes. Based on decode-and-forward (DF) or amplify-and-forward (AF) cooperation scheme, the cooperative schemes such as Co-UWSN [25], SPARCO [26], and CoDBR [27] have been developed for multi-hop UWA-SN to improve the performance further. All of these are the beneficial exploration and practice to obtain the cooperative transmission gain in the underwater acoustic channels with limited bandwidth. ...
The limited energy supply of underwater nodes is one of the key issues for the multi-hop underwater acoustic sensor networks (UWA-SN). In this paper, the fusion scheme based on ant colony optimization algorithm (ACOA), artificial fish swarm algorithm (AFSA) and dynamic coded cooperation (DCC) strategy, named as ACOA-AFSA fusion DCC routing algorithm, has been proposed for routing in the multi-hop UWA-SN, aiming at simultaneously reducing the energy consumption and enhancing the robustness. In the proposed ACOA-AFSA fusion DCC routing algorithm, the randomness of the AFSA and the positive feedback mechanism of the ACOA enable the algorithm to find the global optimal routing more efficient and accurate. In addition, most existing routing protocols consider the large-scale networks (more than 100 nodes), while the medium- and small-scale networks (less than 100 nodes) are more practical in nowadays' multi-hop UWA-SN. The network scale affects the optimal design of routing protocols in terms of energy saving. Considering the practical situation, we compare the proposed scheme with other four existing artificial intelligence (AI) routing algorithms in the medium- and small- scale multi-hop UWA-SN, which is instructive for application of AI in practical multi-hop UWA-SN. The simulation results show that the proposed ACOA-AFSA fusion DCC routing algorithm can reduce the energy consumption by 40.1% compared to that with non-cooperative strategy in the multi-hop UWA-SN with 20 nodes. The proposed routing algorithm also consumes less energy than other four existing AI routing algorithms in the medium-scale multi-hop UWA-SN with 50 nodes or 100 nodes. However, for the small-scale case with 10 nodes, the advantage is not very obvious. In the meantime, the proposed ACOA-AFSA fusion DCC algorithm is compatible with the ACOA-AFSA fusion non-cooperative algorithm, and the complexity is acceptable, which is very appealing to the time-varying marine environments.
... While information is forwarded to cooperative partners of a node in the lack of MS. In [14], CoDBR(Cooperative Depth Based Routing) is suggested to achieve data reliability and efficiency throughput. Potential cooperative routing relays are chosen based on their corresponding depths. ...
Underwater wireless sensor networks (UWSNs) is an developing area for research in the wireless sensor networks (WSN) area. The normal method is to adapt for underwater use presently accessible terrestrial architectures and well-proven architectures. Underwater Wireless Sensor Networks (UWSNs) have drawn a lot of concentration to help multiple applications such as tracking pollution, tsunami warnings, offshore exploration, tactical tracking, etc. For many applications, the efficiency and reliability of the network in terms of high performance, energy conservation, low bit error rate (BER) and reduced delay are prerequisites. However, UWSN's unique characteristics such as low bandwidth available, big delay in propagation, extremely vibrant network topology, and high probability of error pose many difficulties in the development of effective and reliable communication protocols. Therefore, in this proposed work, along with its mathematical model, we suggest a protocol that focuses on improving network reliability and effectiveness through cooperative routing and sink mobility. For reliable data transmission, cooperative transmission is well known. Based on their residual energy data and depth , prospective relay and target nodes for cooperative routing are chosen in this algorithm. Data from the source node is transferred in a cooperative way to the target node via the relay node. Mobile Sinks collect information straight from the nodes of the location. We consider as selection parameters the depth threshold of the source node, the residual energy of the destination nodes/ potential relay and the SNR of the relating source node to the potential relay / destination node. In this work, two distinct selection criteria for partner nodes are also introduced and contrasted. Partner node selection (relay / destination node) for cooperative routing should be carried out on the grounds of a certain criterion in order to achieve efficient outcomes. Based on the extensive simulations carried out in MATLAB, we note that our suggested method increases performance in terms of energy efficiency, network life and decreases BER relative to the existing depth-based routing protocols.
... CoDBR protocol, presented in [46], is an extension of DBR protocol with cooperation employed at network layer. CoDBR is an enhanced version of DBR, which uses cooperative diversity. ...
Underwater sensor networks (UWSNs) play a significant role in ocean exploration and monitoring by gathering information and routing it to the ground stations. Therefore, the design of efficient routing protocols is necessary as it guarantees robust and reliable data delivery from the source nodes to the destination nodes. However, the effects of underwater environment, dynamic nature of the channel for acoustic, radio and optical waves, and harsh underwater noise conditions, make the routing protocol design a challenging task. This article overviews various issues which are faced in designing the routing protocols and summarizes the popular routing protocols for UWSNs alongside their pros and cons. More specifically, the routing protocols are characterized into three main categories; localization-based, localization-free and cooperative schemes. The performance of these protocols are discussed with respect to various network parameters such as energy consumption, network lifetime, delay, reliability, and communication overheads. Towards the end, new directions for potential research in improving routing protocols performance in UWSNs are highlighted.
... CoDBR protocol, presented in [46], is an extension of DBR protocol with cooperation employed at network layer. CoDBR is an enhanced version of DBR, which uses cooperative diversity. ...
Underwater sensor networks (UWSNs) play a sig- nificant role in ocean exploration and monitoring by gathering information and routing it to the ground stations. Therefore, the design of efficient routing protocols is necessary as it guarantees robust and reliable data delivery from the source nodes to the des- tination nodes. However, the effects of underwater environment, dynamic nature of the channel for acoustic, radio and optical waves, and harsh underwater noise conditions, make the routing protocol design a challenging task. This article overviews various issues which are faced in designing the routing protocols and summarizes the popular routing protocols for UWSNs alongside their pros and cons. More specifically, the routing protocols are characterized into three main categories; localization-based, localization-free and cooperative schemes. The performance of these protocols are discussed with respect to various network parameters such as energy consumption, network lifetime, delay, reliability, and communication overheads. Towards the end, new directions for potential research in improving routing protocols performance in UWSNs are highlighted.
... Incorporating co-operation with an existing routing protocol called DBR an unique scheme called cooperative DBR (CoDBR) has been proposed by Nasir et al. The main aim of this protocol is to improve reliability and throughput [38]. In DBR, a source node broadcasts the data to its neighboring node. ...
Water covers a greater part of the earth's surface. Even though we know very little about the underwater world as most parts of it remain unexplored. Oceans including other water bodies hold huge natural resources and also the aquatic lives. These are mostly unexplored and very few of those are known due to unsuited and hazardous environments for the human to explore. This vast underwater world can be monitored remotely from a distant location with much ease and less risk. To monitor water-bodies remotely in real-time, sensor networking has been playing a great role. It is needed to deploy a wireless sensor network over the volume which we want to surveil. For vast water bodies like oceans, rivers and large lakes, data is collected from the different heights of the water level which is sent to the surface sink. Unlike terrestrial communication, radio waves and other conventional mediums can't serve the purpose of underwater communication as they pose high attenuation and very reduced transmission range. Rather an acoustic medium can transmit data more efficiently and reliably in comparison to other mediums. To transmit data reliably from the bottom of the sea to the sinks at the surface, multi-hop communication is needed which must involve a certain scheme. For seabed to surface sink communication, leading researchers have proposed different routing protocols. The goal of these routing protocols is to make underwater communication more reliable, energy-efficient and delay efficient thus to improve the performance of the overall communication. This paper surveys the advancement and applications of the routing protocols which eventually helps in finding the most efficient routing protocol for the Underwater Wireless Sensor Network (UWSN).
... In both of the communication energy is the fundamental factor in AWSNs. [9] has no energy balancing technique to reduces each node energy consumption, which decrease the efficiency and network lifetime. The nodes nearer to the sink suffer from the burden of continuous heavy packets transmission in the direction of sink. ...
... The cooperative depth-based routing (CoDBR) was proposed as a unique routing protocol. In CoDBR, this high reliability and improved throughput is achieved at the cost of high end-to-end delay [12]. The data gathering based node coordination (DGNC) scheme [16] was proposed which focused on sparsely distributed USNs and a path-controllable autonomous underwater vehicle (AUV), with no time synchronization between the two. ...
Underwater sensor network is a promising networking technique. Several challenges such as dynamic structure, high rates of energy consumption, long propagation delay, and narrow bandwidth are being faced by underwater sensor networks. The traditional routing approaches never give reliable and expected performance. This paper presents a novel routing algorithm to tackle acoustic transmission problems in underwater. The proposed algorithm is based on cuckoo search and ant colony optimization.
... Whereas, in absence of mobile sink, it is forwarded towards a nodes cooperative partners. In [9], CoDBR (Cooperative Depth Based Routing) is proposed that achieves information reliability and throughput efficiency. Potential relays for cooperative routing are selected on the basis of their respective depths. ...
Underwater Wireless Sensor Networks (UWSNs) have attracted much concentration to support various applications like pollution monitoring, tsunami warnings, offshore exploration, tactical surveillance, etc. Network's efficiency and reliability in terms of high throughput, energy conservation, low Bit Error Rate (BER) and reduced delay are pre-requisites for many applications. However, distinctive features of UWSNs like low available bandwidth, large propagation delay, highly dynamic network topology, and high error probability pose many challenges for devising efficient and reliable communication protocols. In this thesis, we therefore propose a protocol along with its mathematical model that focuses on enhancing network reliability and efficiency via cooperative routing and sink mobility. Cooperative transmission is well known for reliable data transfer. Many cooperative communication protocols have been developed which investigate the physical and MAC layer aspects to improve link efficiency in harsh underwater environment, however, at network layer, it is still unexplored. Similarly, cooperative routing is not yet collaborated with sink mobility. We present a dominating set based cooperative routing algorithm at network layer. In this algorithm, potential relay and destination nodes for cooperative routing are selected on the basis of their depth and residual energy information. Data from source node is forwarded towards the destination node via relay node in a cooperative manner. Mobile Sinks directly gather data from destination nodes. Two different partner node selection criteria are also implemented and compared in this work. Selection of partner node (relay/destination node) for cooperative routing is to be performed on the basis of a certain criterion so that effective results can be achieved. We consider source node's depth threshold, potential relay/destination nodes's residual energy and Signal to Noise Ratio of the link connecting source node with potential relay/destination node as selection parameters. Based on the comprehensive simulations implemented in MATLAB, we observe that our proposed work improves the performance in terms of network lifetime, energy efficiency, throughput and reduces BER as compared to the existing depth based routing protocols.
... There are many protocols based on DBR, such as EEDBR, EEDBR &DDBR, DBMR, CoDBR [2][3][4][5], etc. In EEDBR, although energy balance is achieved, large amounts of hello packets consume extra energy. ...
An energy efficiency routing protocol based on Depth-Based Routing (DBR) protocol for data collection scene is proposed. Protocol utilizes probe packet to calculate the difference between the minimum signal-to-noise ratio (SNR) required to correctly receive a packet and actual SNR of received request, and then adjust transmission power to send a large amount of data. Hence, the energy of sender can be saved. Simulation shows that the energy efficiency of the protocol can be improved about 20% compared to DBR.
... Every node ascertains its alive neighbor sensors to refresh profundity edge level in organize instatement stage. Researchers in [22], use that to take care of various issues happened in UWSNs, Improved routing arrangement is required for productive information sending. This paper proposed enhanced agreeable plan to build the life time and unwavering quality of the UWSNs. ...
... Every node ascertains its alive neighbor sensors to refresh profundity edge level in organize instatement stage. Researchers in [22], use that to take care of various issues happened in UWSNs, Improved routing arrangement is required for productive information sending. This paper proposed enhanced agreeable plan to build the life time and unwavering quality of the UWSNs. ...
One of the real issues in UWSN is congestion control. The need is to plan an optimized congestion control scheme which enhances the network life time and in addition limits the usage of energy in data transmission from source to destination. In this paper, we propose a routing protocol called Dist-Coop in UWSN. Dist-Coop is a distributed cooperation based routing scheme which uses mechanism for optimized congestion control in noisy links of underwater environment. It is compact, energy proficient and high throughput opportunistic routing scheme for UWSN. In this proposed protocol architecture, we present congestion control with cooperative transmission of data packets utilizing relay sensors. The final objective is to enhance the network life time and forward information utilizing cooperation procedure, limiting energy consumption amid transmission of information. At destination node, combining strategy utilized is based on Signal-to-Noise Ratio (SNRC). Simulation results of Dist-Coop scheme indicate better outcomes in terms of energy consumption, throughput and network lifetime in contrast with Co-UWSN and EH-UWSN routing protocols. Dist-Coop has expended substantially less energy and better throughput when contrasted with these protocols.
... The approach is not suitable for high density networks as network complexity and energy consumption increases with increase in node density. On the basis of minimum depth, CoDBR (Nasir et al., 2014), selects next forwarder along with two relaying nodes. With more nodes participating in routing, CoDBR consumes more energy and thus the network dies out earlier than DBR. ...
Routing in underwater acoustic network is challenging because of longer delays and mobility caused on account of ocean currents and tides. Existing algorithms focus only on delivery of packets with very little consideration to minimising packet delay. In this paper, we propose a new beacon-based routing algorithm for underwater sensor networks using multiple sink architecture. Delay minimising depth-based routing (DMDBR) attempts to minimise delay and uses depth, hop count and residual energy for making routing decisions. Novelty of our scheme is in a node accepting packets for forwarding only if it has sufficient energy for forwarding all the packets in the packet queue. A node declines acting as a forwarder once the estimated residual energy is insufficient to forward the new packets. Simulation results show that DMDBR improves packet delivery ratio and lowers end-to-end delay in comparison to depth-based routing.
... Threshold-Optimized DBR (AMCTD) explored the optimal weight function to achieve longer network lifetime [12]. CoDBR was proposed in succession in [18]. To enhance network performance, CoDBR used a cooperation-based scheme. ...
Underwater Acoustic Networks (UANs) adopt acoustic communication. The opening and sharing features of underwater acoustic channel make communication in UANs vulnerable to eavesdropping and interfering, and UANs appeal for higher security. This paper presents a secure and depth-based anonymous routing (SDBR) protocol tailored for UANs. Based on bilinear pairings and hash function, by involving limited computation and communication resources, SDBR protocol achieves the backward and forward secrecy for underwater depth-based routing protocol. Theoretical analysis shows that SDBR protocol can provide identity confidentiality, location privacy and routing anonymity as well as decrease computation and communication costs.
The reliability of Underwater Wireless Sensor Networks (UWSNs) is measured in terms of energy consumption (EC), end-to-end delay(E2E), and packet delivery ratio (PDR). The adverse effects of a channel may cause data loss. Reducing delay up to the possible extent improves the reliability of the network, also increasing the number of nodes in a particular network increase reliability. Besides, increasing the number of nodes improves reliability but also increases power consumption. In order to overcome these shortcomings, the two routing protocols are proposed in this paper, namely Delay and Reliability Aware Routing (DRAR) protocol and Cooperative Delay and Reliability Aware Routing (Co-DRAR) protocol for UWSNs. In the DRAR protocol, the network is divided into two equal regions where two sink nodes(SNs) are positioned at the upper region of the network and two SNs are placed at the mid-region of the network. The protocol chooses the relay node based on residual energy (RE), distance, and Bit Error Rate (BER). These parameters protect the data packets from corruption and also provide a stable path (where nodes remain active for longer periods and do not die quickly). The protocol uses a single link and may get worse sometimes while changing channel circumstances. To address this problem, a cooperative routing scheme is added to the DRAR protocol in order to develop its enhanced version known as the Co-DRAR protocol. The protocol works by allowing the destination to receive multiple copies of data packets in order to decide the quality of packets. The proposed protocols DRAR and Co-DRAR perform routing irrespective of the geographical position of sensor nodes conversely to some conventional routing protocols. This is why our proposed protocols perform than the well-known protocol i.e. Depth base routing (DBR) in terms of EC, E2E, PDR, dead nodes, packet drop ratio, and number of alive nodes (ANs).
The ocean contains abundant resources and has high scientific and economic values. Increasing underwater communication scenarios stimulates many research efforts on underwater wireless ad-hoc networks. Underwater acoustic communication technology supports medium to long-range wireless communication. However, it suffers from low transmission data rates and long link delays. This paper introduces an Acoustic-Radio Cooperation Network (ARCNet) model for more efficient maritime information transmission. Under this ARCNet, we propose a new Radio-Acoustic Opportunistic Hybrid (RAOH) routing protocol composed of a neighbor discovery mechanism and a hybrid routing strategy. In the neighbor discovery stage, we explore the surface radio links to aid in selecting the shortest delay path between an underwater node and the surface nodes. In the route establishment stage, we combine the advantages of opportunistic routing and on-demand routing and design an opportunistic hybrid routing strategy, which improves the success rate of data forwarding and reduces the time spent on route establishment. Simulation results show that the proposed RAOH protocol outperforms traditional terrestrial and underwater routing strategies in routing response speed, packer delivery rate, throughput, end-to-end delay, and energy efficiency.
The Underwater sensor network (UWSN), also known as Marine Sensor Network (MSN), is gaining increasing attention due to its applications in the monitoring of the marine environment and assisting Marine Intelligent Transportation Systems (MITS). Such systems provide in-vehicle assistance services (i.e., traffic monitoring and driver alerts) by gathering transportation and environmental information. Though very promising, there are several barriers to developing energy-efficient communication protocols for heterogeneous MSN, including selecting optimal routing paths twinned with the lifetime of these sensor nodes along the path, which are restricted due to the limited energy storage capacity. Hereby, the selection of an optimal route path also necessitates harvesting and management of the sensor nodes’ energy. To facilitate this, the current work presents REER-H, a Reliable Energy Efficient Routing protocol with Harvesting for cluster-based MSN capable of multi-source energy harvesting and an incorporated energy management technique. Incorporating three separate layers of the protocol stack, namely, network, MAC, and physical layers, REER-H uses its proposed adaptive scheduling technique to support collision-free data transmission by assigning adaptive time slots based on demand and data load. Also, the proposed integrated energy harvesting and management solves the energy hole problem and enhances the overall network lifetime. In comparison to the existing cooperative and cluster-based energy-efficient routing protocols for underwater maritime communication, the simulated results using Network Simulator-3 (NS3) reveal that the proposed scheme remarkably enhances the overall network performance in terms of packet delivery ratio, throughput, lifetime energy consumption, and end-to-end delay for MSN.
Owing to the hasty growth of communication technologies in the Underwater Internet of Things (UIoT), many researchers and industries focus on enhancing the existing technologies of UIoT systems for developing numerous applications such as oceanography, diver networks monitoring, deep-sea exploration and early warning systems. In a constrained UIoT environment, communication media such as acoustic, infrared (IR), visible light, radiofrequency (RF) and magnet induction (MI) are generally used to transmit information via digitally linked underwater devices. However, each medium has its technical limitations: for example, the acoustic medium has challenges such as narrow-channel bandwidth, low data rate, high cost, etc., and optical medium has challenges such as high absorption, scattering, long-distance data transmission, etc. Moreover, the malicious node can steal the underwater data by employing blackhole attacks, routing attacks, Sybil attacks, etc. Furthermore, due to heavyweight, the existing privacy and security mechanism of the terrestrial internet of things (IoT) cannot be applied directly to UIoT environment. Hence, this paper aims to provide a systematic review of recent trends, applications, communication technologies, challenges, security threats and privacy issues of UIoT system. Additionally, this paper highlights the methods of preventing the technical challenges and security attacks of the UIoT environment. Finally, this systematic review contributes much to the profit of researchers to analyze and improve the performance of services in UIoT applications.
Underwater is a harsh and dynamic environment. Its physical properties are unsteady in the space-time domain and that complicates the communication process inside the water. Moreover, underwater transmissions suffer from many attenuations and scattering sources due to several environmental noises such as shipping, turbulence, wave dynamics, and the background life of the marine organisms. In this chapter, we introduce the underwater communication basics and challenges compared with terrestrial networks, then illustrate the Internet of Underwater Things (IoUT) network structure and the underwater node architecture, and finally, overview the machine learning modeling in underwater communication.
Underwater channels are considered challenging media in communication due to the harsh nature of such environments. However, dynamic transmission can assist in finding sub-optimal solutions by adaptively changing the employed techniques, e.g., the forwarding scheme between nodes, modulation methods, coding parameters (e.g., coding rate), and the transmitted signal intensity control (or transmission power level control), to compromise for the instantaneous fluctuations in various underwater environments. Moreover, opportunistic and cooperative communications are necessary to compensate for the prompt changes in underwater environments. In this chapter, we discuss an opportunistic cooperative transmission scheme for underwater networks that is adaptable for various environmental conditions. The scheme employs the key physical variables of the seawater, e.g., temperature, salinity, density, and wave speed, to indicate the proper relaying scheme jointly with the appropriate modulation method and the transmitting power level that suit the current transmission situations.
Underwater channels are considered challenging media in communication due to the harsh nature of such environments. However, dynamic transmission can assist in finding sub-optimal solutions by adaptively changing the employed techniques, e.g. the forwarding scheme between nodes and the transmitted signal intensity control, to compromise for the instantaneous fluctuations in various underwater environments. Additionally, Machine Learning (ML) techniques can provide appropriate solutions for various problems e.g. routing, resource allocation, and energy-efficiency to further enhance the quality of the communication systems. In this paper, we propose a novel dynamical transmission framework for multi-hop Internet of Underwater Things (IoUT) and underwater networks to fit for various conditions. The proposed framework employs a heuristic forwarding scheme selection approach beside an adaptive transmission signal intensity method. We also propose a decision-tree based ML-model that adaptively learns the proper forwarding method beside the appropriate amount of the transmitted signal intensity for each relay node to minimize the transmission error rate and the power consumption depending on numerous parameters e.g. node location, link reliability and certain water quality metrics such as water temperature, depth, and pH measurements. The model achieves remarkable accuracy for training and testing patterns beyond the 99%.
Wireless Sensor Networks (WSNs), particularly Wireless Body Area Networks (WBANs) and Underwater Wireless Sensor Networks (UWSNs) are important building blocks of upcoming generation networks. Sensor networks consist of less expensive nodes having the features of wireless connectivity, very less transmission power, limited battery capacity and resource constraints. Due to low cost and small size, sensor nodes allow very big networks to be installed at a viable price and develop a link between information systems and the real globe. Cooperative routing exploits the transmission behavior of wireless medium and communicates cooperatively by means of neighboring nodes acting as relays. Prospective relays as well as the destination nodes are chosen from a set of near-by sensors that use distance and Signal-to-Noise Ratio (SNR) of the link conditions as cost functions
– this contributes to significant reduction in path-loss and enhanced reliability. In this dissertation, we propose three schemes Link Aware and Energy Efficient protocol for wireless Body Area networks (LAEEBA), Incremental relay-based Cooperative Critical data transmission in Emergency for Static wireless BANs (InCo-CEStat) and Cooperative Link Aware and Energy Efficient protocol for wireless Body Area networks (Co-LAEEBA). These protocols are efficient in terms of link-losses, reliability and throughput. Consideration of residual energy balances load among sensors, and separation and SNR considerations entrust reliable data delivery. As a promising technique to mitigate the effect of fading, cooperative routing is introduced in the functionality of LAEEBA and Co-LAEEBA protocols. Similarly, incremental relaying in InCo-CEStat account for reliability. Simulation results show that our newly proposed schemes maximize the network stability period and network life-time in comparison to other existing schemes for WBANs. In Underwater Acoustic Sensor Networks, demand of time-critical applications leads to the requirement of delay-sensitive protocols. In this regard, this disserta- tion presents five routing protocols for UWSNs; Cooperative routing protocol for Underwater Wireless Sensor Networks (Co-UWSN), Cooperative Energy-Efficient model for Underwater Wireless Sensor Networks (Co-EEUWSN), Analytical ap- proach towards Reliability with Cooperation for Underwater sensor Networks (AR- CUN), Reliability and Adaptive Cooperation for Efficient UWSNs (RACE) and Stochastic Performance Analysis with Reliability and COoperation for UWSNs (SPARCO). In these protocols, physical layer’s cooperative routing is explored for the design of network layer routing schemes that prove to be energy-efficient as well as path-loss aware. The concentration is focused on Amplify-and-Forward (AF) scheme at the relay nodes and Fixed Ratio Combining (FRC) technique at the destination nodes. Nodes cooperatively forward their transmissions taking benefit of spatial diversity to reduce energy consumption. Simulations are conducted to validate the performance of our proposed schemes in comparison to the selected existing ones. Results demonstrate the validity of our propositions in terms of selected performance metrics.
Underwater wireless sensor networks have received increased attention in recent years due to its numerous applications in oil spills detection, ocean exploration, submarine detection and disaster avoidance. All these applications make use of a number of sensor nodes deployed in different depths in the ocean for data collection and communication. Efficient communication in the network of sensor nodes requires a dynamic routing approach. Most of the routing protocols proposed for traditional sensor networks cannot be used for underwater sensor networks due to its unique characteristics such as dynamic topology, limited bandwidth, high energy utilization and increased latency. Considering these unique features, efficient routing protocols are exclusively designed for underwater sensor networks. The latest opportunistic routing protocols proposed for underwater sensor network guarantees very high Quality of Service to all the applications. This research paper presents a survey and comparison of all the latest opportunistic routing protocols that has been designed for underwater sensor networks. We then discuss the issues and challenges with each of these opportunistic protocols with future research directions.
Mission critical applications impose the requirements of reliability and network
efficiency on Underwater Wireless Sensor Networks (UWSNs). Many cooperative
communication protocols are developed investigating physical and Media Access Control
(MAC) layer aspects to improve link efficiency, however, at network layer, it is still
largely un-explored. In this thesis, we propose a cooperative diversity routing protocol for
UWSNs to enhance network performance. Cooperation is employed at network layer in
existing non-cooperative routing protocol, Depth Based Routing (DBR), to increase its
reliability and throughput. Potential relays are selected on the basis of depth information.
Data from source node is cooperatively forwarded to the destination by relay nodes.
Simulation results show that Cooperative DBR (CoDBR) gives more throughput, more
packet acceptance ratio and less packet drop as compared to non-cooperative scheme.
Additionally, in this thesis, incremental relaying cooperative diversity with
retransmissions for UWSN is also studied and two routing protocols, based on
incremental relaying with cooperative retransmissions, are also proposed to enhance
reliability and throughput of the network. In the proposed model, feedback mechanism
indicates success or failure of data transmission. If direct transmission is successful, there
is no need of relaying by cooperative relay nodes. In case of failure, relays retransmit the
signal one by one till the desired signal quality is achieved at destination. Furthermore,
mathematical expression for the number of available relays along with closed-form
expression for outage probability is determined. Results show that the incremental
relaying with cooperative retransmissions can achieve less outage and more throughput
as compared to regular cooperative diversity networks.
Underwater wireless sensor networks (UWSNs) have gained attention due to their
applications in pollution monitoring, military surveillance, marine aquatic environment
monitoring, disaster prevention, resource investigation, oil/gas extraction, etc.
UWSNs consist of sensor nodes and sink nodes. Sensor nodes are deployed under the
water to perform monitoring task and report required information to sink. Sensor
nodes have limited battery power and unable to recharge. Therefore, UWSNs need an
energy efficient routing scheme to prolong stability period and network lifetime. This
research work presents two routing schemes (an energy efficient and balanced energy
consumption cluster based routing protocol for underwater WSNs (EBECRP) and
Courier based weighting depth forwarding area division DBR protocol for underwater
WSNs (CB-WDFAD-DBR)) which aim to improve stability period and network
lifetime. In EBECRP, we use the concept of clustering to reduce multi hoping which
results in more energy consumption. This protocol avoids depth based routing and
use mobile sink to balance load on nodes. In CB-WDFAD-DBR, we use courier nodes
to minimize load on the nodes which are close to water surface. We divide the whole
network into different cuboid. In each cuboid there is one courier node which collects
data from the nodes in that cuboid. Moreover, Sparse node deployment and dynamic
network topology in UWSNs result in void hole problem. In this dissertation, we avoid
void hole and present two more interference-aware routing protocols for UWSNs (Intar:
interference-aware routing and Re-Intar: reliable Intar). In proposed protocols,
we use sender based approach to avoid the void hole. The beauty of proposed schemes
is that they not only avoid void hole but also reduce the probability of collision in
dense nodes region by selecting next forwarder with least number of neighbors. The
proposed Re-Intar also uses one hop backward transmission at the source node to
further improve the packet delivery ratio of the network. Simulations are conducted
to validate the performance of the proposed schemes with existing ones.
In this paper, we propose a cooperative transmission scheme for underwater acoustic sensor networks to enhance the network performance. Relay nodes are exploited as virtual antennas to achieve diversity gains. Based on the distinct characteristics of the underwater channel such as high transmission loss, propagation delay, and ambient noises, the paper presents a distributed cooperative scheme including networking protocols and cooperative transmissions at the physical layer in order to enhance the reliability by providing diversity gains through intermediate relay nodes. Destinations and potential relays are selected from a set of neighbor nodes that utilize distance cost and local measurement of the channel conditions into calculation. The simulation and numerical results show that the proposed scheme outperforms the traditional direct transmission schemes in terms of average energy consumption, packet delivery ratio, and end-to-end delay.
In recent research of wireless communication, the concept of cooperative diversity has been put forward and used widely. A number of transmission schemes designed for radio communications could not be directly applied to underwater network, where channel characteristics are more complicated. In this paper, we consider a situation comparatively closer to the realistic underwater acoustic communication and investigate the relay selection problem. Considering the long propagation delay caused by low speed of sound, we design a cooperative transmission scheme. In this scheme, the network chooses the optimal relay or the suitable number of nodes adapting to the changes of underwater circumstances. Then the signal-to-noise ratio (SNR) is added to the criterion of relay selection to realize a more effective algorithm.
Cooperative communication has been studied extensively as a promising technique for improving the performance of terrestrial wireless networks. However, in underwater cooperative acoustic networks, long propagation delays and complex acoustic channels make the conventional relay selection schemes designed for terrestrial wireless networks inefficient. In this paper, we develop a new best relay selection criterion, called COoperative Best Relay Assessment (COBRA), for underwater cooperative acoustic networks to minimize the one-way packet transmission time. The new criterion takes into account both the spectral efficiency and the underwater long propagation delay to improve the overall throughput performance of the network with energy constraint. A best relay selection algorithm is also proposed based on COBRA criterion. This algorithm only requires the channel statistical information instead of the instantaneous channel state. Our simulation results show a significant decrease on one-way packet transmission time with COBRA. The throughput and delivery ratio performance improvement further verifies the advantages of our proposed criterion over the conventional channel state based algorithms.
Due to its efficiency, reliability and better channel and resource utilization, cooperative transmission technologies have been attractive options in underwater as well as terrestrial sensor networks. Their performance can be further improved if merged with forward error correction (FEC) techniques. In this paper, we propose and analyze a retransmission protocol named Cooperative-Hybrid Automatic Repeat reQuest (C-HARQ) for underwater acoustic sensor networks, which exploits both the reliability of cooperative ARQ (CARQ) and the efficiency of incremental redundancy-hybrid ARQ (IR-HARQ) using rate-compatible punctured convolution (RCPC) codes. Extensive Monte Carlo simulations are performed to investigate the performance of the protocol, in terms of both throughput and energy efficiency. The results clearly reveal the enhancement in performance achieved by the C-HARQ protocol, which outperforms both CARQ and conventional stop and wait ARQ (S&W ARQ). Further, using computer simulations, optimum values of various network parameters are estimated so as to extract the best performance out of the C-HARQ protocol.
Recently, underwater wireless sensor networks (UWSNs) have attracted much research attention from both academia and industry, in order to explore the vast underwater environment. UWSNs have peculiar characteristics; that is, they have large propagation delay, high error rate, low bandwidth, and limited energy. Therefore, designing network/routing protocols for UWSNs is very challenging. Also, in UWSNs, improving the energy efficiency is one of the most important issues since the replacement of the batteries of underwater sensor nodes is very expensive due to the unpleasant underwater environment. In this paper, we therefore propose an energy efficient routing protocol, named (energy-efficient depth-based routing protocol) EEDBR for UWSNs. EEDBR utilizes the depth of sensor nodes for forwarding data packets. Furthermore, the residual energy of sensor nodes is also taken into account in order to improve the network lifetime. Based on the comprehensive simulation using NS2, we observe that EEDBR contributes to the performance improvements in terms of the network lifetime, energy consumption, and end-to-end delay. A previous version of this paper was accepted in AST-2011 conference.
In dense underwater sensor networks (UWSN), the major confronts are high
error probability, incessant variation in topology of sensor nodes, and much
energy consumption for data transmission. However, there are some remarkable
applications of UWSN such as management of seabed and oil reservoirs,
exploration of deep sea situation and prevention of aqueous disasters. In order
to accomplish these applications, ignorance of the limitations of acoustic
communications such as high delay and low bandwidth is not feasible. In this
paper, we propose Adaptive mobility of Courier nodes in Threshold-optimized
Depth-based routing (AMCTD), exploring the proficient amendments in depth
threshold and implementing the optimal weight function to achieve longer
network lifetime. We segregate our scheme in 3 major phases of weight updating,
depth threshold variation and adaptive mobility of courier nodes. During data
forwarding, we provide the framework for alterations in threshold to cope with
the sparse condition of network. We ultimately perform detailed simulations to
scrutinize the performance of our proposed scheme and its comparison with other
two notable routing protocols in term of network lifetime and other essential
parameters. The simulations results verify that our scheme performs better than
the other techniques and near to optimal in the field of UWSN.
This article presents a contemporary overview of underwater acoustic communication (UWAC) and investigates physical layer aspects on cooperative transmission techniques for future UWAC systems. Taking advantage of the broadcast nature of wireless transmission, cooperative communication realizes spatial diversity advantages in a distributed manner. The current literature on cooperative communication focuses on terrestrial wireless systems at radio frequencies with sporadic results on cooperative UWAC. In this article, we summarize initial results on cooperative UWAC and investigate the performance of a multicarrier cooperative UWAC considering the inherent unique characteristics of the underwater channel. Our simulation results demonstrate the superiority of cooperative UWAC systems over their point-to-point counterparts.
SUMMARY Recently, underwater wireless sensor networks (UWSNs) have attracted much research attention to support various applications for pollution monitoring, tsunami warnings, offshore exploration, tactical surveillance, etc. However, because of the peculiar characteristics of UWSNs, designing communication protocols for UWSNs is a challenging task. Particularly, designing a routing protocol is of the most importance for successful data transmissions between sensors and the sink. In this paper, we propose a reliable and energy-efficient routing protocol, named R-ERP2R (Reliable Energy-efficient Routing Protocol based on physical distance and residual energy). The main idea behind R-ERP2R is to utilize physical distance as a routing metric and to balance energy consumption among sensors. Furthermore, during the selection of forwarding nodes, link quality towards the forwarding nodes is also considered to provide reliability and the residual energy of the forwarding nodes to prolong network lifetime. Using the NS-2 simulator, R-ERP2R is compared against a well-known routing protocol (i.e. depth-based routing) in terms of network lifetime, energy consumption, end-to-end delay and delivery ratio. The simulation results proved that R-ERP2R performs better in UWSNs.Copyright © 2012 John Wiley & Sons, Ltd.
Due to high bandwidth-efficiency, Multiple-Input Multiple-Output (MIMO) has emerged as a promising technique to address the low bandwidth challenges in underwater acoustic networks. Although extensive research has been conducted at the physical layer for underwater MIMO communications, the corresponding medium access control (MAC) is still largely unexplored, which makes it difficult to apply the existing underwater MIMO technologies in real applications. In this paper, we propose a distributed MAC protocol, called Coordinated Transmission MAC (CT-MAC), for underwater MIMO based network uplink communications. In CT-MAC, an efficient coordination scheme among immediate neighbors is designed for channel competition, which can avoid flooding overhead in the network. This scheme could also effectively address the long propagation delay problem and the collisions among long control packets in underwater acoustic communications. Protocol performance in terms of throughput and energy efficiency is evaluated via simulations which show significant improvements over handshaking based and random access based MIMO MAC approaches.
Underwater acoustic communications (UAC) features frequency-dependent signal attenuation, long propagation delay, and doubly-selective fading. Thus, the design of reliable and efficient UAC protocols is very challenging. On the other hand, cooperative relay communications, which can provide reliable data transmission, is a very attractive technology for UAC. In our recent work, we proposed a practical asynchronous relaying protocol tailored for UAC: Asynchronous Amplify-and-forward relaying with Precoded OFDM (AsAP). This protocol resolves both the time synchronization difficulty and the frequency-selective issue of UAC channels. However, the AsAP protocol adopts fixed amplification and uniform power allocation among the source and the relays, which limits the system performance. Thus, in this paper, we design a modified AsAP system with an instantaneous amplification scheme, and investigate the optimum power allocation based on the criteria of maximum average SNR at the destination. Assuming statistical channel state information (CSI) is available, we analyze the average SNR at the destination and perform the power optimization on the AsAP system. The analytical results suggest a selective relaying scheme, where only the relay with best average SNR forwards the source information. Therefore, we propose an AsAP protocol with selective relaying (SR-AsAP). Finally, the performance of the new SR-AsAP scheme is simulated, and the benefits are illustrated through comparison with the direct-link system and the AsAP protocol.
This article presents a contemporary overview of underwater acoustic communication (UWAC) and investigates physical layer aspects on cooperative transmission techniques for future UWAC systems. Taking advantage of the broadcast nature of wireless transmission, cooperative communication realizes spatial diversity advantages in a distributed manner. The current literature on cooperative communication focuses on terrestrial wireless systems at radio frequencies with sporadic results on cooperative UWAC. In this article, we summarize initial results on cooperative UWAC and investigate the performance of a multicarrier cooperative UWAC considering the inherent unique characteristics of the underwater channel. Our simulation results demonstrate the superiority of cooperative UWAC systems over their point-to-point counterparts.
In this paper, we investigate the use of cooperative communications for high performance data dissemination in dense wireless
sensor networks. We first identify the limitations of existing cooperative schemes. While we previously proposed a multi-hop
cooperative data dissemination scheme, REER, to address these limitations, the construction of such structure relies on a
pre-established reference path. The partially centralized approach makes REER unscalable when encountering network dynamics.
To address this issue, this paper proposes a novel distributed multi-hop cooperative communication scheme (DMC), which is
fully distributed and consists of two operation phases: (1) cooperative mesh structure (CMS) construction, and (2) CMS-based
data dissemination, which includes random value-based scheme and distance-based scheme for forwarding node selection. Simulation
results show that DMC performs well in terms of a number of QoS metrics, and fits well in large-scale networks and highly dynamic environments.
KeywordsCooperative communication–Wireless sensor networks–Data dissemination
Multi-path fading, one of the key factors that deteriorate quality of service (QOS) in Underwater Acoustic Networks (UANs), is investigated under different underwater scenarios in this paper. To improve the Bit Error Rate (BER) performance, the techniques of cooperative diversities are applied. Considering realistic physical model and cooperative diversity techniques, two asynchronous forwarding schemes, namely Underwater Amplify-and-Forward (UAF) and Underwater Decode-and-Forward (UDF), are proposed and analyzed. The results show that both UDF and UAF have better performance than direct transmission. Furthermore, an adaptive and hybrid forwarding scheme is proposed based on UAF and UDF.
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.
In underwater acoustic communications (UAC), frequency-dependent signal attenuation, long propagation delay and doubly-selective fading channels render reliable communications a challenging problem, especially at long distances. To enhance reliability and to extend range, relay communications have been extensively studied in terrestrial environments. However, their application to UAC has not been thoroughly explored. In this paper, we analyze the capacity of relay-aided (RA- )UAC. The result shows a prominent capacity increase in RA-UAC systems, when compared with traditional direct-link UAC. In addition, effects of various system parameters on capacity are also evaluated. These parameters include source-to-destination distance, transmit power allocation and relay location. To realize the benefits of RA-UAC, special considerations are to be taken in practical RA-UAC system designs. To account for and to take advantage of the unique characteristics of UAC channels, we develop a practical asynchronous amplify-and-forward (AF) relay system for UAC. To collect the ample multipath energy and diversity enabled by this relaying protocol, we also employ the precoded orthogonal frequency division multiplexing (OFDM) as the basic physical layer module. Our system resolves both the time synchronization difficulty and frequency selectivity of UAC. Simulations and comparisons are presented to verify our analysis and design.
Reliable delivery of sensory data to a sink node in large scale sensor networks is a challenging problem. We tackle this problem by assuming dense deployment of sensors, which allows us to exploit diversity in choosing intermediate nodes for reliability and energy-efficiency. The proposed reliable and Energy-Efficient Routing (REER) protocol is based on the geographic routing approach. The central idea of REER is the notion of Reference Nodes (RNs), which means the nodes closest to the ideal locations between the source and to the sink. The multiple Cooperative Nodes (CNs) around RNs will contend to relay data packets; thus, there is no overhead of route discovery and REER is resilient to node failures and transmission errors. By adjusting the distances between RNs, we can control the trade-off between reliability and energy-efficiency, which is validated by both analysis and simulation.
DBR: depth-based routing for underwater sensor networks, NETWORKING Ad Hoc and Sensor Networks, Wireless Networks
- H Yan
- Z J Shi
- J H Cui
H. Yan, Z. J. Shi and J. H. Cui, DBR: depth-based routing for underwater sensor networks, NETWORKING Ad Hoc and Sensor Networks,
Wireless Networks, Next Generation Internet, 2008, Springer Berlin
Heidelberg p.72-86.
AM-CTD: Adaptive Mobility of Courier nodes in Threshold-optimized DBR Protocol for Underwater Wireless Sensor Networks
- M R Jafri
- S Ahmed
- N Javaid
- Z Ahmad
- R J Qureshi
M. R. Jafri, S. Ahmed, N. Javaid, Z. Ahmad and R. J. Qureshi, AM-CTD: Adaptive Mobility of Courier nodes in Threshold-optimized DBR
Protocol for Underwater Wireless Sensor Networks. Eighth International
Conference on Broadband and Wireless Computing, Communication and
Applications (BWCCA), 2013.