Deep Reinforcement Learning Methods for Energy-Efficient Underwater Wireless Networking

The wireless sensor networks have been developed and extended to more expanded environments, and the underwater environment needs to develop more applications in different fields, such as sea animals monitoring, predict the natural disasters, and data exchanging between underwater and ground environments. The underwater environment has almost the same infrastructure and functions with ground environment with some limitations, such as processing, communications, and battery limits. In terms of battery limits, many techniques have been proposed; in this chapter, the authors will focus in deep reinforcement learning techniques.

Machine Learning Techniques for Underwater Wireless Sensor Networks

With the enormous growth of sensor networks, information seeking from such networks has become an invaluable source of knowledge for various organizations to enhance the comprehension of people interests. Not only wireless sensor networks (WSNs) but its various classes also remain the hot topics of research. In this chapter, the primary focus is to understand the concept of sensor network in underwater scenario. Various mechanisms are used to recognize the activities underwater using sensor which examines the real-time events. With these features, a few challenges are also associated with sensor networks, which are addressed here. Machine learning (ML) techniques are the perfect key of success to resolve such issues due to their feasibility and adaption in complex problem environment. Therefore, various ML techniques have been explained to enhance the operational performance of WSNs, especially in underwater WSNs (UWSNs). The main objective of this chapter is to understand the concepts of UWSNs and role of ML to address the performance issues of UWSNs.

Error Control and Reliable Data Delivery in UWSNs

Underwater wireless sensor networks (UWSNs) contains many components such as vehicles and sensors that are deployed for cooperative monitoring and data collection tasks in a particular acoustic environment various nodes and ground-based stations use these networks interactively. Presently, UWSNs face the problems and obstacles regarding limited bandwidth, high propagation delay, 3D topology, media access control, routing, resource utilization, and power constraints. The research community has developed different methodologies over the past few decades to address these issues and challenges; but, due to complex characteristics of the underwater environment, some of them are still open to research. The main drawback of the traditional approach is the lack of direct interaction between different ends, recorded information can never be accessed during any mission, and data recorded will be lost in the event of any failure.

Underwater Localization Techniques

Underwater acoustic communication uses sound waves to trans-receive information, diving deep inside water, environment scanning, undersea explorations, disaster prevention, etc. In this chapter, an attempt has been made to cover stationary and mobile localization algorithm. They are further subdivided into distributed and centralized. Each one is further subcategorized into estimation-based and prediction-based schemes. The category therefore extends on the basis of ranging method, communication, and synchronization, some of which are area localization, sensor-based localization, forming a sensor array, motion-aware self-localization, silent localization. Each one will be discussed in detail in this chapter. At last, hybrid technique is also discussed, which combines stationary and mobile techniques. The discussion includes various nodes including anchor node, unknown node, sink node, and reference node. Various methods to follow the techniques are also discussed, which include anchor-based method, ranging method, and message communication.

Firewall in Underwater Wireless Sensor Networks

In this technological arena, a firewall is a major tool for network security system to predetermine its basic rules so that it can control and monitor incoming and outgoing network traffic. The firewall generally restricts the faulty and unusual data entering the system. It can be categorized as host-based firewalls and network-based firewalls. There are various applications of firewall and how these firewalls can help the underwater wireless sensor network (UWSN) in protecting the sensor nodes where a huge amount of sensitive data is communicated among different countries. Firewall mainly aims to secure the network from different attacking devices and the attackers in a very efficient way. Firewall creates a barrier in which only the authorized data can be passed through after continuously checking by the firewall policies. To protect a local system and network of system from threats which are generally network based firewall is the most effective way. The design of the firewall is required to be accurate as it acts as a filter at higher protocol layer and some levels of IP-packets.

Congestion Control Protocols for UWSNs

UWSN is a grid of many purposes of self-operating nodes with various applications related to various disciplines such as hydrographic surveys, tactical surveillance, disaster prevention, and bathymetry. The process of transmission and reception of messages by propagating sound in an underwater environment is known as acoustic communication. Transmission of acoustic waves is the only method to communicate underwater, as radio waves get attenuated severely and there is severe scattering in optical transmission. Underwater wireless sensor networks (UWSN) have important applications in the exploration of underwater. UWSNs have various applications like in exploration of the sea, collection of data, monitoring of pollution, surveillance of tactics, prevention of disaster, in applications of ministry and surveying of mines.

Smart City in Underwater Wireless Sensor Networks

The earth is covered 71% by water and the human utilizes the remaining 29% for their shelter and living. The idea of living under the water is possible only in fiction movies for our ancestors. But in this century, the idea of living in an underwater city has become a reality with the development of the existing technology. The exploration of the undersea is booming in the science community, which shows the path for underwater cities, underwater museum, and underwater hotels. This chapter contributes the information related to underwater smart cities in three folds: (1) discusses the major challenges in developing the underwater infrastructure, (2) introduces the internet of underwater things components involved in interconnecting the devices for underwater acoustic communication, (3) list the examples of the existing masterpiece architecture constructed underwater.

Secure Communication Techniques for Underwater WSNs

Earth is solitary among the rocky planets revolving in the solar system. It is the only planet that is 3/4 covered with oceans of liquid water. In today's era, wireless sensor network is used in almost places and also is an interesting topic for researchers too. But with the advancement in technology, a network similar to wireless sensor network can be deployed under the water with acoustic signals for data transmission. Because of harsh environment and some more challenges, underwater communication becomes tricky. Underwater wireless sensor networks (UWSNs) is an advanced technology for underwater explorations and have demonstrated their quality in underwater applications. UWSN is a blend of wireless technology with sensor technology that has some extraordinary features like smart sensing, intelligent computing, and communication capabilities. Further, to maintain the secure communication underwater, it becomes more and more tricky. This chapter presents an expansive analysis of challenges, attacks, and security techniques of UWSNs.

Recent and Future Node Deployment Strategies in the Underwater Sensor Network (UWSN)

The chapter focuses on the recent development in the field of the sensor node deployment in the UWSN (under water wireless sensor network). In the chapter, the technical challenges during the node deployment of the sensor nodes in the UWSN (under water wireless sensor network) are represented with prefacing the background. The chapter focuses on the different methods of node deployment and presents a generalized model for ensure the reliability. A view of analyzing the deployment of sensor nodes is also shown in the example by following the recent researches in the domain. Finally, the future scope and conclusion is represented with the idea of new paradigms in the deployment of sensor nodes in the UWSN.

Quality Enhancement in Underwater Sensor Networks Through Node Deployment Plans

Due to widespread applications and an orientation towards dimensionality enhancement, the underwater sensor networks (UWSNs) are going to be in demand for today's researchers. The core idea to design a strong and reliable build under the water revolves around the master plan of sensor deployment. The quality parameters like coverage, connectivity, and network lifespan, etc. are considered as main pillars for these deployment plans. There is always a trade-off between these quality parameters. So, it is quite necessary to maintain a balance among these parameters in order to establish a successful communication system. In this chapter, the authors have categorized the node deployment plans on the basis of the above-stated quality parameters. During this categorization, the view of dimensionality enhancement from two dimensions to three dimensions is also kept in the mind.