-A testbed is a large evaluation tool. However, to construct a suitable tool with capable architecture, the information about wanted requirement is required. Many existing testbeds are developed without obvious definition of requirements. Therefore, the research efforts may be halted due to the lack of the precisely defined requirements~\cite{ref186}. The tests and experiments on a large number of sensor nodes lead to a scalability challenge, and a large amount of data for logging, debugging, and measurement output. There are no enough tools so as to deal (semi-)automatically with the amount of data and supporting the researchers to evaluate their systems.
+A testbed is a large hardware evaluation tool. However, to construct a suitable tool with capable architecture, the information about the desired requirements is required. For instance, table \ref{Tablex:ch3} presents each research topic and the required abilities and provisions for a specialized testbed in the corresponding field of study~\cite{ref186}. Many existing testbeds are developed without obvious definition of requirements. Therefore, the research efforts may be halted due to the lack of the precisely defined requirements~\cite{ref186}. The tests and experiments on a large number of sensor nodes lead to a scalability challenge, and a large amount of data for logging, debugging, and measurement output. Another drawback is that there are no enough tools to deal (semi-)automatically with the amount of data and supporting the researchers to evaluate their systems.
+
+
+\begin{table}[h]
+\caption{WSN research topics vs testbed requirements}
+\label{Tablex:ch3}
+\resizebox{\textwidth}{!}{%
+\begin{tabular}{|c|c|}
+\hline
+\textbf{WSN research topic} & \textbf{Testbed requirement} \\ \hline
+Energy efficiency & Energy consumption estimation and measurement \\ \hline
+Mobile sensor nodes & Mobile nodes and localization infrastructure \\ \hline
+Realistic WSN context & Deployment in target environments \\ \hline
+Scalability and performance in WSNs & simulations and hybrid testbeds, large network size \\ \hline
+Sensor node design & Development of sensor nodes, monitoring, measurement, debugging \\ \hline
+Interoperability and platform support & Support for different platforms, heterogeneity \\ \hline
+Application and protocol design & Tool support for development,debugging and deployment \\ \hline
+\end{tabular}
+}
+\end{table}