# Conceptual Framework for Future WSN-MAC Protocol to Achieve Energy Consumption Enhancement
## 3 State-of-the-Art Approaches for MAC-Protocols Optimization
### MAC Scheduling in Cross Layer Design  
The concept of Cross Layer Design (CLD) was proposed in the research of WSNs compared with classical networks. It refers to modifying the traditional OSI standard of layers of networks and customization according to the application's need. As we can observe in Figure 3, there is intercommunication between layers in a cross-layer design, making it more efficient in fulfilling the application requirements than a classical layered network. Figure 3 shows a conceptual design of a cross-layer network. Many researchers have had proposals for CLD that involve changing the layers and the architecture from one to another to support the application requirements. In some systems, these might be latency constraints, throughput, or emergency limitations. The survey of [58] provides a thorough discussion of CLD and the various related challenges. [PERSON] et al. [59] proposed a cross-layer design for a multi-hop, self-healing, and self-forming tactical network that minimizes the time of call setup, delivering collision-free communication and reusing the Time Division Multiple Access (TDMA) protocol empty slots. However, this can result in high delay and low throughput. [PERSON] et al. [60] proposed a cross-layer MAC design with transmit antenna selection (TAS) and transmit power adaptation (TPA). As an implementation of vehicle-to-vehicle (V2V) communication, we are \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Reference Paper** & **Approach** & **Type** & **Contribution** & **Results** \\ \hline \multirow{8}{*}{[54]} & \multirow{8}{*}{Resaltime scheduling and power allocation using deep neural networks} & \multirow{8}{*}{Asynch} & An allocation was carried out for the channel resources among multiple small cells in order to enable an uplink or downlink for each cell at a time-slot. A deep Q-network (DQN) estimates a suitable schedule; then, a DNN allocates power corresponding schedule & Decreases end-to-end delay and packet loss \\ \cline{1-1} \cline{2-5}  & \multirow{2}{*}{Realtime scheduling and power allocation allocation using deep neural networks} & \multirow{2}{*}{Asynch} & Frequency and time-slot resources are allocated for sensors based on an NN trained to predict the best channel–slot pair for transmission & \multirow{2}{*}{Decreases the number of collisions} \\ \cline{1-1} \cline{2-5}  & \multirow{2}{*}{A} & \multirow{2}{*}{Synch-TMDA} & \multirow{2}{*}{Synch-TMDA} & \multirow{2}{*}{Synch-TMDA} \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & \multirow{2}{*}{A} & \multirow{2}{*}{Synch-TMDA} & \multirow{2}{*}{Synch-TMDA} & \multirow{2}{*}{Decreases the number of collisions} \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & \multirow{2}{*}{Cognitive radio and machine learning for intelligent wireless communications} & \multirow{2}{*}{Asynch} & Spectrum sensing and access of supervised, unsupervised, and reinforcement learning for wireless communication & \multirow{2}{*}{Enhances spectrum efficiency and energy efficiency} \\ \hline \multirow{8}{*}{[56]} & \multirow{8}{*}{Hybrid MAC Protocol data collection in WSN} & \multirow{8}{*}{Asynch-CSMA} & In the UAV-based wireless network, a hybrid medium access protocol (MAC) is used to collect data. There are two important times in the frame: traction and gathering. CSMA/CA is employed throughout the registration procedure, and the likely notice schedule is assigned to each node recorded during the collection period & \multirow{8}{*}{Increases network throughput and data packet delivery} \\ \cline{1-1} \cline{2-5}  & \multirow{2}{*}{Hybrid MAC Protocol data collection in WSN} & \multirow{2}{*}{Asynch-CSMA} & \multirow{2}{*}{Asynch-CSMA} & \multirow{2}{*}{Synch-TMDA} \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & & & & \\ \cline{1-1} \cline{2-5}  & & & & \\ \hline \hline \end{tabular}
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