# A Unified Vendor-Agnostic Solution for Big Data Stream Processing in a Multi-Cloud Environment
## 4 MC-BDP Prototype Evaluation
### Experimental Results
#### 4.1.6 Container Network Utilisation (GB Received by Workers)  
Based on the summary results presented in Table 8 for the total number of GB received over the network, the following conclusions were drawn: (i) total number of GB received over the network by velocity for scalability--means of three or six workers (single and multiple) are significantly different from each other for all combinations except for three workers (single, multiple). The same conclusion is drawn for almost all possible combinations of three workers (single and multiple) x six workers (single and multiple), except for three workers (single) x six workers (multiple); (ii) total number of GB received over the network by velocity for fault tolerance -there is no significant difference in the means for all combinations, except for six workers (single x multiple); (iii) total number of GB received over the network by velocity for technology agnosticism--all means for three or six workers (Beam) x (single, multiple) are not significantly different from each other. There is a significant difference for three workers (Flink) (single x multiple) and (Flink) [three workers (single) x six workers (single, multiple)], while the rest of the combinations show no significant difference. The means of different numbers of workers (three, six, ten) are significantly different from each other, while the number of containers per node (one, two, four) are not significantly different from each other for the total number of GB received over the network by windowing rate. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{Velocity} & \multicolumn{3}{c}{
\begin{tabular}{c} Three Workers \\ (n = 3) \\ \end{tabular} } & \multicolumn{3}{c}{Six Workers (n = 6)} & \multicolumn{3}{c}{Mann–Whitney U Test Results} \\ \hline  & Single & Multi & Single & Multi & Three Workers and Three Workers (Single and Multi) \\ \hline
1 min & 3.91 & 3.53 & 7.94 & 5.17 & \(p\)-value = 0.4857, accept Ho \\ \hline
1 sec & 4.80 & 4.17 & 7.57 & 5.18 & Three Workers and Six Workers ([S,S] x [M,M]) \\ \hline
100 ms & 3.32 & 3.58 & 7.38 & 4.84 & \(p\)-value = 0.01587, reject Ho (S,S) \\  & & & & & \(p\)-value = 0.02684, accept Ho (S,M) \\  & & & & & \(p\)-value = 0.01587, reject Ho (M,S) \\ \hline
10 ms & 4.84 & 3.36 & 5.72 & 5.73 & \(p\)-value = 0.01587, reject Ho (M,M) \\ \hline
1 ms & NA & NA & 9.64 & 12.49 & Six Workers and Six Workers (Single and Multi) \\ over the Network by Velocity & & & & & \(p\)-value = 0.2222, reject [PERSON] \\ \hline \multirow{2}{*}{Velocity} & \multicolumn{3}{c}{
\begin{tabular}{c} Three Workers (n = 3 ) \\ \end{tabular} } & \multicolumn{3}{c}{Six Workers (n = 6)} & \multicolumn{3}{c}{Mann–Whitney U Test Results} \\ \hline  & Single & Multi & Single & Multi & Three Workers and Three Workers (Single and Multi) \\ \hline
1 min & 1.91 & 2.02 & 5.52 & 5.58 & \(p\)-value = 0.8857, accept [PERSON] \\ \hline
1 sec & 1.66 & 1.94 & 6.34 & 4.71 & Three Workers and Six Workers ([S,S] x [M,M]) \\ \hline
100 ms & 2.95 & 1.90 & 4.64 & 4.75 & \(p\)-value = 0.02857, accept Ho (S,S) \\  & & & & & \(p\)-value = 0.02857, accept Ho (S,M) \\  & & & & & \(p\)-value = 0.02857, accept Ho (M,S) \\ \hline
10 ms & 1.46 & 1.62 & 5.27 & 5.64 & \(p\)-value = 0.02857, accept Ho (M,M) \\ \hline
1 ms & NA & NA & NA & NA & Six Workers and Six Workers (Single and Multi) \\ \hline Average & & & & & \(p\)-value = 0.2222, reject Ho \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Network utilisation (gigabytes received over the network)—graphs and regression models. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multicolumn{11}{c}{\multirow{2}{*}{Velocity}} & \multicolumn{4}{c}{\ \begin{tabular}{c} Three Workers \\ (n = 3) \\ \end{tabular}