Fig 1.
System framework.
Fig 2.
Testbed 3D model – automated box sorting plant.
Fig 3.
Testbed logic flowchart.
Fig 4.
AWS Node-RED flow with WebSocket-Out node.
Fig 5.
AWS Node-RED flow with WebSocket-In node.
Fig 6.
Local Node-RED flow with WebSocket-In node and S7 node.
Fig 7.
Local Node-RED flow with WebSocket-Out node and S7 node.
Table 1.
Summary statistics of elapsed time per variable condition.
Fig 8.
WebSocket round-trip latency analysis.
(a) WebSocket round-trip latency distribution. (b) WebSocket summary statistics of elapsed time.
Fig 9.
Modbus round-trip latency analysis.
(a) Modbus round-trip latency distribution. (b) Modbus summary statistics of elapsed time.
Fig 10.
MQTT round-trip latency analysis.
(a) MQTT round-trip latency distribution. (b) MQTT summary statistics of elapsed time.
Fig 11.
OPC UA round-trip latency analysis.
(a) OPC UA round-trip latency distribution. (b) OPC UA summary statistics of elapsed time.
Fig 12.
WebSocket complete time TIA Portal long-term trace.
Fig 13.
MQTT complete time TIA Portal long-term trace.
Fig 14.
OPC UA complete time TIA Portal long-term trace.
Fig 15.
Modbus complete time TIA Portal long-term trace.
Table 2.
Summary of CPU frame time.
Fig 16.
CPU usage analysis captured in Unity Profiler.
Table 3.
Network traffic data captured by Wireshark.
Fig 17.
Bandwidth usage over time.
Fig 18.
Distribution of bytes transmitted by protocols.
Table 4.
Load analysis statistic summary.
Fig 19.
Average response time by user load.
Fig 20.
EC2 instance CPU utilization by user load.
Fig 21.
EC2 instance memory utilization by user load.
Fig 22.
EC2 instance average network IN traffic by user load.
Table 5.
Comparison of local and AWS round-trip time (RTT) statistics and latency differences.
Fig 23.
Comparison of mean RTT for each protocol in local and cloud setups.
Table 6.
Protocol comparison and trade-offs.