## 4 Comparison and Discussion
### MAC Approach
Therefore, the signal QoS constraint is ensured at the receiver. However, the end-to-end delay of signals is high because the sensor nodes can transmit in only one slot and then must wait for their turn. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Interference** & & & & & & & & \\
**Mitigation** & **Throughput** & **Spatial** & **Colaborative** & **QoS** & **Channel** & **Channel** & **Channel** & **End-to-** & **Number** \\
**Scheme** & & **Reuse** & **Method** & **Guarantees** & **Parameters** & **Access** & **Delay** & **of** \\ \hline DCM [1] & High & No & No & No & Beacon, data & TDMA [13] & Low & High \\ InterACS [2] & Medium & Low & No & No & SINR & TDMA & High & Very low \\ LRIM [3] & High & No & No & No & BDR [18], TE [19] &
\begin{tabular}{c} CSMA/CA \\ 14 \\ \end{tabular} & High & Medium \\ DRA [4] & High & High & Yes & No & SINR & TDMA & Medium & High \\ Service-based scheduling & Medium & Medium & No & Yes & sensing idle & TDMA & High & Low \\
[29] & & & & & channel & & \\ AIIA [5] & High & Medium & Yes & No & Superframe & TDMA, \\  & & & & time offset & CSMA/CA & High & Low \\ CFT [6] & Medium & No & No & No & CCA [15] & TDMA & High & Medium \\ RIC [7] & Medium & Medium & Yes & No &
\begin{tabular}{c} Coloring \\ message \\ \end{tabular} & TDMA & High & High \\
2L-MAC [3] & High & No & No & Yes & SIFS [16] period & TDMA & High & Medium \\ IMF [9] & High & No & No & No & SINR & TDMA & High & Low \\ CBWS [10] & High & High & Yes & Yes & Group ID & TDMA & Medium & High \\ CS [11] & High & High & Yes & No & SINR [17] & TDMA & High & High \\ AIM [12] & High & Low & Yes & Yes & SINR & TDMA & High & High \\ \hline \hline \end{tabular}  
* Dynamic Coexistence Management; \({}^{2}\) Interference-Aware Channel Switching; \({}^{3}\) Lightweight and Robust Interference Mitigation scheme; \({}^{4}\) Dynamic Resource Allocation; \({}^{5}\) Asynchronous Inter-network Interference Avoidance; \({}^{6}\) Continuous Frame Transmission; \({}^{7}\) Random Incomplete Coloring; \({}^{8}\) Two Layer MAC; \({}^{9}\) Interference Mitigation Factor; \({}^{10}\) Clique-Based WBASN Scheduling; \({}^{11}\) Cooperative Scheduling; \({}^{12}\) Adaptive Internetwork interference Mitigation; \({}^{13}\) Time Division Multiple Access; \({}^{14}\) Carrier Sensing Multiple Access with Collision Avoidance; \({}^{15}\) Clear Channel Assessment; \({}^{16}\) Short Inter-Frame Space; \({}^{17}\) Signal to Interference plus Noise Ratio; \({}^{18}\) Beacon delivery ratio; \({}^{19}\) Transmission Efficiency.  
\end{table} 
Table 2: Comparison of the interference mitigation schemes in the MAC approach. The CS algorithm [36] applies the scheduling scheme and the graph coloring algorithm to mitigate interference at WBASN sensor nodes. The graph coloring algorithm is more effective than DRA [28]. According to the performance study, spatial reuse in the CS algorithm is high because clusters with different colors do not collide. However, the priority of the sensor nodes and the mobility of WBASNs are not considered. Mobility may lead to change in the network topology. As a result, the coloring algorithm and cluster formation may take more time to converge. In summary, the purpose of MAC approach schemes is to reschedule the operating channel of the working WBASN to another channel in time or frequency domain. Some MAC algorithms are acceptable to mitigate interference. The throughput is the most important factor and has been thoroughly investigated to prove the efficiency of interference mitigation. In addition, some requirements are not explored in those schemes, including power consumption, QoS constraint, and end-to-end delay. System performance must be analyzed in terms of those requirements. A comparison of these MAC approach schemes is presented in Table 2.