CyberCertPrepOT Security FundamentalsOT Fundamentals: Network Architecture & ProtocolsHARDFree question
An IDS flags function code 43 with sub-function 14 from an unknown workstation to many PLCs in sequence. What is the most likely intent?
- A.A restart request that reboots each PLC one after the other
- B.A time update that sets the clock on each PLC unit
- C.Reconnaissance that harvests vendor strings from each PLC
- D.A write sweep that changes the pressure setpoint on each PLC
Why C is correct
Function 43 (0x2B) with MEI type 14 is Read Device Identification, returning vendor name, product code, and revision. It changes nothing, so it points to asset discovery or reconnaissance rather than writes, restarts, or time changes.
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