Sardorbek Muminov

A Focus on Practical Assessment of MAC Protocols for Underwater Acoustic Communication with Regard to Network Architecture

Abstract Underwater acoustic communication is a rapidly growing research area nowadays and many related studies have already been conducted in recent decades. Underwater acoustic communication can be easily applied to many fields, such as oceanic data collection, undersea exploration, disaster prevention, underwater environmental monitoring, and tactical surveillance. However, there are many challenges associated with underwater communication, including bandwidth limitations, multi-path propagation, padding, long end-to-end propagation delay, high bit error, temporary loss of connectivity, and limited battery power. To overcome these problems, existing implementable MAC protocols need to be classified in terms of network topology. To improve network mobility, two kinds of network topologies, which include cluster-head-based and ad-hoc-based MAC protocols, are considered. In this paper, we summarize some selected MAC protocols and analyze their performance by comparing a number of factors. We obtain experimental results by developing and simulating the existing numerical models of each protocol practically using simulation tools.

A Focus on Comparative Analysis: Key Findings of MAC Protocols for Underwater Acoustic Communication According to Network Topology

Underwater acoustic communication can be applicable to many fields, such as oceanic data collection, undersea exploration and development, disaster prevention, underwater environmental monitoring and tactical surveillance. However, it has several challenges to design underwater acoustic sensor networks, for instance, limited bandwidth, multi-path, padding, long propagation delay, high bit error, temporary losses of connectivity and limited battery power. Nowadays many studies are being conducted to overcome abovementioned problems. In this paper, various MAC protocols for underwater acoustic communication are classified by network topology, one is cluster head based MAC protocols and the other one is ad-hoc based MAC protocols. In recent researches, there were not comparative analyses of MAC protocols for underwater acoustic communication according to network topology. So, we summarize and analyze these protocols through comparing each other with some factors. In the future, MAC protocols for underwater acoustic communication will be designed with consideration for each advantage of cluster head and ad-hoc MAC protocols, considering the mobility of nodes to improve underwater acoustic communication, which can be applied to lots of underwater applications.

Security in Underwater Acoustic Sensor Network: Focus on Suitable Encryption Mechanisms

Underwater acoustic sensor network (UWASN) technology is advancing recently, and research is increasing rapidly. UWASN can be applicable to many fields such as underwater monitoring, underwater resource exploration, ocean data collection, and military purposes. Existing terrestrial wireless sensor network security mechanisms have not been applied to UWASNs due to interference such as multipath propagation, signal fading, limited bandwidth, slow data rates, and long transmission delays. UWASNs also require security mechanisms and algorithms to maintain data confidentiality and integrity. Security-related research is being actively conducted, but it is still in its nascent stages. Therefore, when considering a UWASN protocol stack, the application layer, when sending data to its sub-layer, needs to encrypt the payload for information security. In this paper, we consider the requirements and security issues of UWASNs. We also discuss applicable security algorithms that are suitable for UWASN.

A Reliable Error Detection Mechanism in Underwater Acoustic Sensor Networks

Underwater Acoustic Sensor Networks (UWASNs) are not secure due to various characteristics of underwater environments. The error rate is very high in underwater environment due to factors such as long propagation delay, fading, multi-path and noises. Moreover, malicious attacks to the network add one more threat to reliable data transport problems. With respect to terrestrial sensor network, UWASNs are very different in nature. Reliable and faster data communication is our main issue. As the signal has to travel inside a noisy wireless acoustic channel so the processing of the signal is also take to measure. Moreover, we know the error rate is always high in underwater, so detecting the error and correcting them is the main key to secure the communication among nodes. The energy efficiency as well as the performance of any mechanism depends on collusion free data transmission and reception among sensors. Data link layer plays a crucial part in the Media Access Control (MAC) operation by detecting errors. For secure communication it is necessary to detect the errors during the transmission and reception. Especially in data link layer, the error detection and correction used some techniques like Cyclic Redundancy Check (CRC), checksum, parity bit, Forward Error Correction (FEC) and different error-correcting codes like Humming code, Reed Solomon code, binary convolution code and others tailored made program. In UWASNs data throughput depends on the packet size and the MAC protocols, where different protocols perform differently. A valid packet size has a great effect on the network. The ideal packet sizes depend on the specific application and the pattern of message it generates. We have to use small size packets which do help faster communication and higher data throughput in UWASNs. In this paper, depends on our practical experience, instead of using any kind of FEC techniques, we used CRC-8 because the process of data transmission usually contains the risk of unwanted modification as the channel is open. Signals arrive to the physical layer at different power and delay due to acoustic effects. So packets need to recheck for reliable data communication in UWASNs.

A Standard Error Detection Mechanism for Underwater Acoustic Sensor Networks

Underwater Acoustic Sensor Networks (UWASNs) have some constant factors like energy limitations and node mobility. Energy is a very crucial issue as any kind of recharging is not possible in underwater environment. Energy consumption in each section is important. Saving a small amount of energy helps the life span of the sensor nodes as well as the lifetime of the networks. Especially for static UWASNs, long-term non-time critical application energy efficiency is of major concern. Beside energy efficient protocol design, error control is important in communication as the issue of data integrity is becoming increasingly important. Allowable error rate and undetected error probability in a network is also calculated for noisy channel. Error control is a system design technique that can fundamentally change the trade-offs in a communication system design. An error detection mechanism with low power consumption is also important for saving energy. In this paper, we have tried to find out how we can save our precious energy during communication among sensor nodes and bio mimetic fish-robots. Especially in security and error checking operation in underwater environment based on different error detection and correction mechanisms.

Biomimetic fish robot controlling system by using underwater acoustic signal

This paper demonstrates Biomimetic fish robot controlling system using by underwater acoustic signal. All the information, results and technical data were collected during implementation in real environment. Through this paper we have focused to create Biomimetic fish robot controlling system with an enhanced design.