### Leveraging Software-Defined Networking (SDNs) in the Design of IIoT-Edge Networks
[84] ranked the Maestro SDN controller as the best performer, having compared it against a wider array of SDN controllers, namely ODL, Floodlight, Beacon, Maestro, IRIS, Ryu, POX, NOX, ONOS, MUL, and Libfluid-based controllers. [PERSON] et al. [86] observed that ODL, despite experiencing memory leakages, had a shorter response time than Floodlight. [PERSON] et al. [102] observed that Ryu and ODL outperformed the ONOS and Floodlight SDN controllers. [PERSON] et al. [103] compared Ryu, POX, ONOS, and Floodlight in an emulated Mininet-Wifi simulation wireless network. An analysis of the four SDN controllers revealed notable differences in performance. Floodlight exhibited superior performance compared to the others, showcasing the low \begin{table}
\begin{tabular}{l l l l l l l l l l l l} \hline \hline Sensors & Controller & Organization & Programming Language & Open Source & Flow/Second & Mod/entity & Probability & Consistency & Fault & Architecture \\ \hline
[84] & CNOS & CNLIab & Java & Java & Java & 1M & High- & Flow & Work- Strong & Vis & Flat-distributed \\ \hline
[99] & OpenFlowLight & Linux Foundation & Java & Java & 10M & High- & Flow & Work & No & Flat-distributed \\ \hline
[99] & Floodlight & Big-Wish Networks & Java & Java & Java & - & Fair & Fair & No & No & Centralized \\  & & & & & & & & & & & & Multi-threaded \\ \hline
[73] & ONNL & Noise Networks & Python & Java & 2.2M & Fair & Fair & Strong & Vis & Distributed \\
[74] & Buscom & Stanford University & Java & Java & 12.8M & Fair & Fair & No & No & Centralized \\  & & & & & & & & & & & & Multi-threaded \\ \hline
[77;200] & Hyperfilter & University of Toronto & C++ & & & 30K & Fair & Fair & Work & Vis & Distributed \\
[84;85] & Maestro & Bio University & Java & Java & 4.8M & Fair & Fair & No & No & Centralized \\  & & & & & & & & & & & Multithreaded \\ \hline
[94] & OpenRLL & KudCloud & C & Java & & & Fair & Fair & No & No & Centralized \\  & & & & & & & & & & & Multithreaded \\ \hline
[91] & RVU & NTT & Python & Java & & 1.8M & Low & Fair & No & No & Centralized \\  & & & & & & & & & & & \\  & & & & & & & & & & & \\  & & & & & & & & & & & \\ \hline
[94] & NOK & Noise & Python & Java & 1.8M & Low & Fair & No & No & Centralized \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Comparison of open-source SDN controllers based on common architectural and operational design features. est delay and jitter. Conversely, Ryu displayed the poorest results in jitter tests, while ONOS exhibited the worst delay performance. Moreover, all controllers performed similarly well in throughput tests. Lastly, [PERSON] et al. [101] qualitatively compared nine SDN controllers, finding that multi-threaded and centralized (Floodlight, OpenMUL, Beacon, Maestro) and distributed (e.g., ODL, ONOS) SDN controllers outperformed the centralized and single-threaded ones (e.g., NOX, POX, Ryu). **For the throughput benchmark:** Experimental studies have assessed the SDN controller's ability to efficiently handle and manage data traffic. According to [PERSON] et al. [84], MUL and Libfluid-based SDN controllers outperformed ODL, Floodlight, Beacon, Maestro, IRIS, Ryu, POX, NOX, and ONOS. Further, [PERSON] et al. [102] and [PERSON] et al. [104] observed that Ryu and ONOS outperformed ODL and Floodlight. **For the architectural and network load benchmark:** Controllers have four key architectural features: multicore support, switch partitioning, packet batching, and packet processing. [PERSON] et al. [92] compared four leading open-source SDN controllers (NOX, Beacon, Maestro, and Floodlight), analyzing their architectural designs. They concluded that controllers aiming for high throughput should use static switch partitioning and packet backing. Controllers focused on delay-sensitive applications should employ adaptive packet and task batching to minimize per-packet latencies. Additionally, sending each control message individually can further enhance latency performance. Further, [PERSON] et al.