## 1 Introduction
The remotely operated underwater vehicles (ROVs) collects data from Tx anchor nodes and deliver it to a central station which makes up the mobile UWSNs [6; 32]. Each underwater sensor node can be autonomous in transmitting data directly to the ROV, depending on how close it is to ROV. Sensors with large amounts of data and proximity to the ROV can use radio links, whereas sensors with small amounts of data and a long distance from the ROV can use acoustic links [33; 34]. Table 1 shows the relevant surveys and their key contributions, scopes and limitations. \begin{table}
\begin{tabular}{c c c c} \hline
**Ref. No** & **Year** & **Key Contribution** & **Scope** & **Limitation** \\ \hline \multirow{7}{*}{[35]} & \multirow{7}{*}{2016} & All the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm-based routing protocol. & \multirow{7}{*}{Energy-efficiency was not the core focus of this work.} \\  & & & \\ \cline{1-1}  
[PERSON] et al. in [36] their review article made an emphasized discussion on routing protocols with respect to node's mobility, which is influenced by factors including vector, depth, clustering, AUW performance, and the path that a sensor node should take. [PERSON] et al. in [37] had held a conversation about localization-based and localization-free routing protocols during which they also discussed some of the relevant issues pertaining to UWSNs, [PERSON] et al. in [35] classified their research into several categories, including the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. [PERSON] et al. in [40] had worked on the concept of data collecting in the UWSN, its classification that is based on routing service parameters, as well as some of the existing difficulties encountered when gathering data. Communication in wireless sensor networks or more specifically we can say in UWSNs requires a lot of power to complete a simple task of establishing a communication live link. However, in the UWSNs it is not possible to reach out very frequently to the power sources that are keeping the system alive so that communication may happen between anchor TX and sensor Rx nodes. In addition, this battery source is drained due to the large amount of energy consumption by the processing unit of a node present in UWSNs. Therefore, we either have to design new processing unit that will have the capacity to perfume tasks using as much less processing energy so that it may help to retain the battery source power for a long time, or take the second option, which is to design and implement efficient protocols that will help in maximum efficient energy consumption on processor level. In addition, through this study we are trying to address the 2 nd aforementioned scenario to make the system more energy efficient which was abandoned by all the aforementioned review articles. This article is unique from other survey articles, because it gives a comprehensive overview of current development of the most recent ALOHA-based, TDMA-based and routing protocols from recent publications for UWSN by highlights the advantages and drawbacks of each. The purpose of this study is to assist research individuals/groups in overcoming the challenges, faced in designing a UWSNs MAC and routing protocol,  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Ref. No** & **Year** & **Key Contribution** & **Scope** & **Limitation** \\ \hline
[37] & 2017 & Provides a comprehensive survey on localization based and localization-free routing protocols. & Covers routing issues and in its associated protocols for UWSNs. & Energy-efficiency was not the core focus of this work.