Underwater Routing Protocols Research Articles

RECAR: Robust and efficient collision-avoiding routing for 3D underwater named data networking

Internet of Underwater Things (IoUT) has important application prospects in fields of both scientific research and commercial business. As a future network architecture, Named Data Networking (NDN) is starting to be applied to IoUT. Although Underwater Named Data Networking (UNDN) has unique advantages in dealing with bandwidth usage, multi-path forwarding, and node mobility, there is still no specific routing protocol for UNDN. The existing underwater routing protocols are either difficult to combine with NDN, or are limited by channel collision and redundant forwarding, especially broadcast suppression routing. In this paper, we propose a routing method named Robust and Efficient Collision-Avoiding Routing (RECAR) for 3D UNDN. RECAR consists of three combined forwarding modes: Directive Mode (DM), Directive Flooding Mode (DFM), and Flooding Mode (FM). In DFM, we propose Segmentation Suppression for Optimal Position (SSOP), an elaborate waiting time algorithm of broadcast suppression which can effectively reduce channel collisions and redundant forwarding. For DM, failure path recovery and unreliable path elimination are proposed to address failure paths. Additionally, several forwarding efficient mechanisms are designed including flexible mode shift, unified data forwarding and scope control. Simulation results show that RECAR has excellent and robust performance, even in the cases of node failure and void hole. Compared with a recent underwater routing method (adaptive location-based routing protocol), RECAR improves the average interest satisfied rate by 19.57% while reducing the request time, collisions, redundant forwarding, total traffic, and energy consumption by 19.5%, 91.7%, 71.4%, 78.4%, and 27.3%, respectively.

Three-Dimensional Iterative Enhancement for Coverage Hole Recovery in Underwater Wireless Sensor Networks

The efficient coverage of underwater wireless sensor networks (UWSNs) has become increasingly important because of the scarcity of underwater node resources. Complex underwater environments, water flow forces, and undulating seabed reduce the coverage effect of underwater nodes, even leading to coverage holes in UWSNs. To solve the problems of uneven coverage distribution and coverage holes, a three-dimensional iterative enhancement algorithm is proposed for UWSN coverage hole recovery using intelligent search followed by virtual force. Benefiting from biological heuristic search algorithms, improved particle swarm optimization is applied for node pre-coverage. With the change in iteration times, the adaptive inertia weight, acceleration factor, and node position are constantly updated. To avoid excessive coverage holes caused by search falling into local optimum, underwater nodes are considered as particles in the potential field whose virtual forces are calculated to guide nodes towards higher coverage positions. In addition, based on the optimal node location obtained by the proposed algorithm, the monitoring area is divided based on the clustering idea. The underwater routing protocol DBR based on depth information is subsequently used to optimize node residual energy, and its average is calculated comprehensively and compared with the other three coverage algorithms using the DBR routing protocol. Based on the experimental data, after 100 iterations, the coverage rates for BES, 3D-IVFA, DABVF, and the proposed algorithm are 83.28%, 88.85%, 89.31%, and 91.36%, respectively. Moreover, the proposed algorithm is further verified from the aspects of different node numbers, coverage efficiency, node movement trajectory, coverage hole, and average residual energy of nodes, which provides conditions for resource development and scientific research in marine environments.

WLQRP: A Weighting Link-Quality-Based Routing Protocol for Underwater Sensor Networks

Due to challenges posed by long propagation distances, high mobility, limited bandwidth, multipath propagation, and Doppler effects in underwater acoustic sensor networks (UASNs), the design of routing protocols faces numerous complexities. To enhance reliability in sparse node regions and reduce network energy consumption, this paper proposes a dependable and energy-efficient routing protocol termed WLQRP for weighting link-quality-based routing protocol. WLQRP leverages link quality information between nodes for data forwarding. When computing the link quality between nodes, it considers not only the historical transmission success ratio between nodes and their immediate relay but also incorporates the link quality between the relay and the relay’s next-hop nodes. This approach effectively reduces the likelihood of encountering void regions. Moreover, the protocol judiciously selects the next-hop node to improve transmission success rates, thereby minimizing data packet retransmissions and reducing energy consumption. We conduct MATLAB simulations to evaluate the WLQRP protocol, comparing it against the VBF (vector-based forwarding) and the HH-VBF (hop-by-hop vector-based forwarding) underwater routing protocol. Experimental results demonstrate that WLQRP enhances network performance in terms of data transmission rate, energy consumption, and end-to-end delay. These findings validate the efficacy of the proposed protocol.

HCAR: A Hybrid-Coding-Aware Routing Protocol for Underwater Acoustic Sensor Networks

Because of the characteristics of the underwater acoustic sensor networks (UASNs), such as long propagation delay, narrow bandwidth, limited resources, and intermittent connectivity, the design of the routing protocol has always been the focus and difficulty in UASNs research. Most of the existing coding-based underwater routing protocols only use the error correction function of network coding to improve the reliability of data transmission, ignoring that the network coding can effectively optimize the performance of packet transmission. In this paper, we propose a hybrid coding-aware routing protocol (HCAR). HCAR introduces inter-flow network coding and designs a new routing framework that combines reactive routing with opportunistic routing. It exhaustively explores potential coding opportunities in the network and proactively creates coding opportunities during the entire routing process, which enables HCAR to take full advantage of the broadcast nature of the wireless medium, thereby effectively reducing the number of transmissions. In addition, we design a new encoding method that does not rely on opportunistic listening, and thus avoids introducing excessive delay and overhead. The simulation results show that HCAR can effectively optimize the routing problem of the networks with multiple source nodes and a single sink node, further reducing the transmission overhead while ensuring reliability. We also implemented the key mechanism of HCAR protocol to verify its feasibility through sea tests.

Overview of Underwater Wireless Communication Routing Protocols

Underwater wireless communication is the use of acoustic, optical, electromagnetic waves and other technologies to send information underwater. This article reviews existing routing protocols for underwater wireless communication network design. Particular attention is paid to their performance in terms of communication efficiency, data rate, latency, and packet loss. The different types of routing protocols are discussed in detail, highlighting their respective strengths and weaknesses. This article also covers issues related to security and scalability and how they affect the performance of the entire network. Finally, this paper discusses the future trend of underwater routing protocols and proposes promising research directions.

PDDQN-HHVBF Routing Protocol Based on Empirical Priority DDQN to Improve HHVBF

Reinforcement learning (RL) has been successfully applied to underwater routing protocols due to its powerful ability of distributed decision making. However, the traditional RL has slow convergence speed and low learning efficiency in underwater. Meanwhile, too many studies focus on using RL to find low hop paths rather than short distance paths in underwater routing, while the long distance of ocean communication is the significant reason for the packets collision and energy loss in underwater. Based on the above problems, this paper proposes the PDDQN-HHVBF (Empirical Priority DDQN to Improve Hop-by-Hop Vector-Based Forwarding) protocol for M-UWSNs (Mobile source node Underwater Wireless Sensor Networks), in which AUV (Autonomous Underwater Vehicle) is used as source node to collect data and transmit data hop-by-hop to Sink node through underwater nodes. The proposed protocol is adopt to find the optimal relay nodes in pipeline referred HHVBF protocol by requesting the max Q value according to three states of the residual energy of nodes, the number of candidate relay nodes and the geographical location information of all candidate relay nodes in time. This because PDDQN-HHVBF avoids the strong correlation between data samples, and its playback samples will not be too concentrated or lead to over fitting. It can converge rapidly in underwater environment. In addition, the requesting Q value mechanism related to the geographical location information can find the optimal relay node with short distance propagation in large-scale networks, which will reduce the number of packets collision, and then saving energy and improving network lifetime. In addtion, the in-time requesting for Q value can cope with the nodes drift affected by ocean current movement. In addition, the Q value related to the residual energy of nodes and the number of candidate relay nodes will effectively load balancing nodes, prolong network lifetime and avoid routing holes. Finally, the “Store-Carry-Forward” mechanism proposed for AUV, this mechanism store and carry packets when facing routing holes until find the optimal relay node for forwarding, which will improve PDR and save energy of AUV significantly. The simulation results show that, the proposed PDDQN-HHVBF protocol converges about 30% faster than DQELR. Although its delay is higher than DQELR and ROEVA for requesting Q value. It outperforms VBF, HHVBF, DQELR, and ROEVA in terms of energy efficency, PDR, and lifetime, which are analyzed by varying speed of nodes from 0 m/s to 3 m/s with 1000 nodes and varying number of nodes from 500 to 3000 with speed in 1 m/s.

Securing localization-free underwater routing protocols against depth-spoofing attacks

Localization-free depth-based opportunistic routing protocols are an energy efficient choice for underwater wireless sensor networks (UWSNs). However, most depth-based routing protocols are vulnerable to sinkhole attacks caused by depth spoofing. In this paper, we propose an energy-efficient depth-based probabilistic routing protocol (DPR) that is resilient against depth spoofing. By encouraging unqualified (suboptimal) relay nodes to randomly forward data packets, the adversarial effects of depth-spoofing can be mitigated. As the randomized forwarding probability increases, a better packet delivery ratio can be achieved when under depth-spoofing attacks. To keep energy consumption in check, we propose a simulation-based methodology for finding the optimal forwarding probability. By adjusting the unqualified node forwarding probability, the proposed DPR protocol can effectively resist depth-spoofing attacks with a reasonably efficient energy overhead. A delivery ratio exceeding 90% can be achieved under attack with energy overhead as low as 35% under normal conditions. In comparison with relevant existing protocols, the proposed protocol achieves better energy efficiency, resilience efficiency, and scalability.

Energy efficient and link reliable routing (E2LR) scheme for underwater sensor networks

Underwater Sensor Network (USN) is the wireless network infrastructure applicable in deep ocean to detect, collect, and transmit information to a remote data acquisition location on shore. Underwater routing protocols are used to provide route information in addition to ensuring efficient data and information collection and transmission. Some routing strategies for USNs are linked to high energy consumption, high end-to-end delay and shorter network lifetime. These issues are due to unnecessary packet flooding especially during route establishment, improper selection of next hop neighbor and frequent communication for route maintenance. Considering these challenges, this paper presents a localization free energy efficient and link reliable (E2LR) routing protocol that controls unnecessary flooding of hello packets to reduce energy consumption in the information distribution phase. Further, E2LR calculates the link quality using a composite metric for next hop selection which ultimately reduces end-to-end delay and regularly updates the energy status in order to achieve optimization during routing operations. Simulation results show that E2LR exhibit higher performance than both H2-DAB and R-ERP2R in terms of energy efficiency during information distribution phase and data forwarding phase. Moreover, E2LR also shows superior performance regarding end-to-end delay, network lifetime and packet delivery ratio than compared protocols.

Reinforcement Learning-Based Opportunistic Routing Protocol for Underwater Acoustic Sensor Networks

Due to the problems of high bit error rate and delay, low bandwidth and limited energy of sensor nodes in underwater acoustic sensor network (UASN), it is particularly important to design a routing protocol with high reliability, strong robustness, low end-to-end delay and high energy efficiency which can flexibly be employed in dynamic network environment. Therefore, a reinforcement learning-based opportunistic routing protocol (RLOR) is proposed in this paper by combining the advantages of opportunistic routing and reinforcement learning algorithm. The RLOR is a kind of distributed routing approach, which comprehensively considers nodes’ peripheral status to select the appropriate relay nodes. Additionally, a recovery mechanism is employed in RLOR to enable the packets to bypass the void area efficiently and continue to forward, which improves the delivery rate of data in some sparse networks. The simulation results show that, compared with other representative underwater routing protocols, the proposed RLOR performs well in end-to-end delay, reliability, energy efficiency and other aspects in underwater dynamic network environments.

A Survey of Routing Protocols for Underwater Wireless Sensor Networks

Underwater wireless sensor network (UWSN) is currently a hot research field in academia and industry with many underwater applications, such as ocean monitoring, seismic monitoring, environment monitoring, and seabed exploration. However, UWSNs suffer from various limitations and challenges: high ocean interference and noise, high propagation delay, narrow bandwidth, dynamic network topology, and limited battery energy of sensor nodes. The design of routing protocols is one of the solutions to address these issues. A routing protocol can efficiently transfer the data from the source node to the destination node in the network. This article presents a review of underwater routing protocols for UWSNs. We classify the existing underwater routing protocols into three categories: energy-based, data-based, and geographic information-based protocols. In this article, we summarize the underwater routing protocols proposed in recent years. The proposed protocols are described in detail and give advantages and disadvantages. Meanwhile, the performance of different underwater routing protocols is analyzed in detail. Besides, we also present the research challenges and future directions of underwater routing protocols, which can help the researcher better explore in the future.

Design of Algorithms and Protocols for Underwater Acoustic Wireless Sensor Networks

Nowadays, with the recent advances of wireless underwater communication and acoustic sensor devices technology, we are witnessing a surge in the exploration and exploitation of the ocean’s abundant natural resources. Accordingly, to fulfill the requirements of the exploration of the ocean, researchers have focused their work toward the design of methods and algorithms for the underwater acoustic sensor networks (UASNs). Although considerable research effort has been devoted to the development of a variety of UASN-based applications, very limited work has addressed the algorithmic design and analysis for UASN. To this end, we propose to provide a comprehensive design, development, and analysis of algorithms and protocols for UASNs. We discuss each of the fundamental UASN building blocks, such as (i) underwater acoustic communication channel modeling, (ii) sustainable coverage and target detection, (iii) Medium Access Control (MAC-layer design and time synchronization, (iv) localization algorithms design, and (v) underwater routing protocol. Then, we illustrate the different protocols from each category and compare their benefits and drawbacks. Finally, we discuss a few potential directions for future research related to the design of future generations of UASNs.

USPF: Underwater Shrewd Packet Flooding Mechanism through Surrogate Holding Time

The selection of optimal relay node ever remains a stern challenge for underwater routing. Due to a rigid and uncouth underwater environment, the acoustic channel faces inevitable masses that tarnish the transmission cycle. None of the protocols can cover all routing issues; therefore, designing underwater routing protocol demands a cognitive coverage that cannot be accomplished without meticulous research. An angle-based shrewd technique is being adopted to improve the data packet delivery, as well as revitalize the network lifespan. From source to destination, one complete cycle comprises three phases indeed; in the first phase, the eligibility of data packet belonging to the same transmission zone is litigated by Forwarder Hop Angle (FHA) and Counterpart Hop Angle (CHA). If FHA value is equal or greater than CHA, it presages that the generated packet belongs to the same transmission zone; otherwise, it portends that packet is maverick from other sectors. The second phase picks out the best relay node by computing a three-state link quality with prefix values using the Additive-Rise and Additive-Fall method. Finally, the third phase renders a decisive solution regarding exorbitant overhead fistula; a packet holding time is contemplated to prevent the packet loss probability. Simulation results using NS2 have been analyzed, regarding packet delivery ratio, packet error rate, communication overhead, and end-to-end delay. Comparing to HHVBF and GEDAR, USPF indeed has outperformed, leading into the evidence of applicability’s favor.

Collaborative Functioning for Underwater Acoustic Sensor Communication using AURP (AUV-Assisted Underwater Routing Protocol)

Security has become one of the most essential requirements in any application domain of wireless sensor networks. It is highly required so that we can send data to an authenticated person on a secure channel ensuring all the aspects of security features like confidentiality, integrity, authentication, etc. are provided. But it is more essential in a domain like underwater acoustic sensor networks where the bandwidth is severely limited, the energy of sensors is limited and the propagation delay is very high and hence we have limited resources that must be utilized efficiently. In order to address these challenges, the proposed work focuses on a mobile agents based architecture consisting of secure co-operation of AURP (An AUV-aided underwater routing protocol) with the objective of providing maximum data delivery and minimum energy consumption. Further these mobile agents are encrypted and embedded in the AUV’s in their buffer for the data capturing process as these mobile agents can travel throughout the network via controlled AUV's. This work uniquely contributes a mobile agent based periodic approach for collecting data from various gateway nodes (cluster heads) of different clusters as specified in its itinerary using travelling sales person so that it covers all of them using an optimal amount of energy & processing them one by one and completing its itinerary and depositing the data to a sink and then repeating the same process again periodically when these AUV’s gets charged exploiting a solar energy. Each cluster has some members within one hop distance that have sensed some data which needs to be sent to a gateway node using encrypted mobile agents and only when some AUV's services are provided to that particular gateway node.

Underwater routing protocols: Analysis of link selection challenges

The sensor nodes deployed in underwater environment has different routing mechanism in contrast to the terrestrial network. Getting underwater data on pollution detection, control of the ecosystem, marine mining, catastrophe avoidance and strategic surveillance thereby demands smooth packet transmission which can only be possible through a stable and astute communication link between sensor nodes. Therefore, selecting best link between source and destination node is a key challenge. The meticulous research has been conducted to search out the best link selection mechanism of bodacious underwater routing protocol EnOR, SURS‐PES and USPF; and recommended the protocol that offers a shrewd communication link. The performance has been evaluated through NS2 simulation for packet delivery ratio, end-to-end delay, network lifespan and network energy consumption.

Evaluation of the Performance of Underwater Wireless Sensor Networks Routing Protocols under High-density Network

Nowadays, research and development of Underwater Wireless Sensor Networks (UWSNs) widely supporting various available application such as oil/gas monitoring system, tsunami monitoring, disaster prevention, and environmental monitoring has become increasingly popular among academicians and industries. However, to develop efficient communication in UWSNs is a difficult duty due to the irregular nature of the underwater environment. In our previous review [14], we did an elaborate theoretical survey on UWSNs routing protocols. In this work, we are going to evaluate the performance of some of the UWSNs routing protocols under high-density network condition. To simulate a high-density UWSNs, we are placing hundreds of underwater nodes in a small three-dimensional topographical area and study the behavior of the routing protocol and the network. We have chosen to evaluate some of the frequently addressed underwater routing protocols such as Underwater Flooding (UWFlooding), Vector-Based Forwarding (VBF), and Hop by Hop Vector-Based Forwarding (HH-VBF) under this high-density network scenarios. The result of our study shows that VBF and HH-VBF perform better in term of the number of packets received, dropped packets and PDR, while UWFlooding performs better in term of cumulative delay.

Fuzzy based energy efficient underwater routing protocol

The routing protocol in the underwater wireless sensor network is very challenging over the traditional network. Sensor nodes are placed in a specified location with their limited energy and hence the performance of the networks is affected like network lifetime and successful packet delivery. Most of the time idle sensor nodes are emitted battery power and when any target is found at that time nodes are not capable of sense and forward ability. To overcome this situation, we proposed a model for fuzzy based cluster head selection that enhances the lifetime of the network. After that we have designed a fuzzy based routing protocol which improves the packet delivery rates significantly. In compared with the existing routing protocol, we have proper utilization of energy consumption and hens it extends the overall performance of the network to overcome challenges in underwater.

Underwater Internet of Things in Smart Ocean: System Architecture and Open Issues

The development of the smart ocean requires that various features of the ocean be explored and understood. The Underwater Internet of Things (UIoT), an extension of the Internet of Things (IoT) to the underwater environment, constitutes powerful technology for achieving the smart ocean. This article provides an overview of the UIoT with emphasis on current advances, future system architecture, applications, challenges, and open issues. The UIoT is enabled by the most recent developments in autonomous underwater vehicles, smart sensors, underwater communication technologies, and underwater routing protocols. In the coming years, the UIoT is expected to bridge diverse technologies for sensing the ocean, allowing it to become a smart network of interconnected underwater objects that has self-learning and intelligent computing capabilities. This article first provides a horizontal overview of the UIoT. Then, we present a five-layer system architecture for the future UIoT, which consists of a sensing, communication, networking, fusion, and application layer. Finally, we suggest the current challenges and the future UIoT research trends, in which cloud computing, fog computing, and artificial intelligence are combined.

A Comprehensive Comparative Analysis of Two Novel Underwater Routing Protocols

The most unmanned area of this planet is sheltered with water; that is roughly 71.9% of the total area of this planet. A large quantity of marine life is present in this area. That is the reason underwater research is bounded due to unexplored benefits. Due to the addition of sensors and growing interests in the exploration and monitoring of marine life Underwater Wireless Sensor Network (UWSN) can play an important role. A variety of routing protocols has been deployed in order to get information between deployed nodes. Providing stable data transmission, maximum throughput, minimum consumption of the energy and delay are challenging tasks in the UWSN. These routing protocols can be Layer-by-Layer Angle-Based Flooding (L2-ABF) and Diagonal and Vertical Routing Protocol (DVRP). In order to get stable data transmission, the node density plays our role in shallow and deep water. Several parameters are employed to evaluate the output efficiency of these routing protocols. In this paper, like an end to end delay, loss of data packets during transmission and data delivery ratio within communication are considered the major parameters for evaluation. For this, the network simulator is used with the aqua sim package. The results, we have produced during this study; guides us about the best routing protocol for data transmission. It finally reveals that the L2-ABF performs better then DVRP in a different situation, further the tradeoffs relationship is achieved against multiple situations.

A Stateless Opportunistic Routing Protocol for Underwater Sensor Networks

Routing packets in Underwater Sensor Networks (UWSNs) face different challenges, the most notable of which is perhaps how to deal with void communication areas. While this issue is not addressed in some underwater routing protocols, there exist some partially state‐full protocols which can guarantee the delivery of packets using excessive communication overhead. However, there is no fully stateless underwater routing protocol, to the best of our knowledge, which can detect and bypass trapped nodes. A trapped node is a node which only leads packets to arrive finally at a void node. In this paper, we propose a Stateless Opportunistic Routing Protocol (SORP), in which the void and trapped nodes are locally detected in the different area of network topology to be excluded during the routing phase using a passive participation approach. SORP also uses a novel scheme to employ an adaptive forwarding area which can be resized and replaced according to the local density and placement of the candidate forwarding nodes to enhance the energy efficiency and reliability. We also make a theoretical analysis on the routing performance in case of considering the shadow zone and variable propagation delays. The results of our extensive simulation study indicate that SORP outperforms other protocols regarding the routing performance metrics.

AREP: An asymmetric link-based reverse routing protocol for underwater acoustic sensor networks

Routing protocol design is one of the fundamental requirements of Underwater Acoustic Sensor Networks (UASNs). However, traditional underwater routing protocols focus on the particularities of underwater environment, while ignoring the features of underwater nodes that influence route establishment. In this study, the impact of the directional beam width of underwater nodes on communication links was fully explored. The presented case studies indicate that for fixed beam width of directional antennas, the relative position change of two geographically adjacent nodes is prone to generate asymmetric links. To ensure bidirectional data communication between source nodes and destination nodes, an asymmetric link-based reverse routing (AREP) is proposed. In AREP, each node maintains a neighbor table in which items are used to analyze the link state. Routing paths are established by prioritizing the utilization of symmetric links. When an asymmetric link is required to be introduced into a routing path, a three-hop-constrained circuitous route will be established for ease of reverse routing search. The routing void problem is addressed in AREP through eliminating void nodes. A routing update is periodically conducted to dynamically adjust previous routing paths to the change of network topology caused by node mobility. Simulation results demonstrated that AREP improves network performance in terms of transmission delay, packet delivery ratio, as well as energy consumption.