EC-Council ICS-SCADA Exam - Topic 3 Question 39 Discussion

Actual exam question for EC-Council's ICS-SCADA exam

Question #: 39
Topic #: 3

[All ICS-SCADA Questions]

What type of communication protocol does Modbus RTU use?

AUDP

BICMP

CSerial

DSSTP

Show Suggested Answer

Suggested Answer: C

Modbus RTU (Remote Terminal Unit) is a communication protocol based on a master-slave architecture that uses serial communication. It is one of the earliest communication protocols developed for devices connected over serial lines. Modbus RTU packets are transmitted in a binary format over serial lines such as RS-485 or RS-232. Reference:

Modbus Organization, 'MODBUS over Serial Line Specification and Implementation Guide V1.02'.

by Devora at Mar 08, 2026, 01:47 PM

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Stephane

25 days ago

Definitely C) Serial. It's widely used in industrial settings.

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Marnie

1 month ago

I was torn between A and C, but C makes more sense for Modbus.

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Lili

1 month ago

Agreed! Serial is the right choice. It's simple and effective.

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Tomas

1 month ago

I think it's C) Serial. Modbus RTU is all about serial communication.

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Alecia

2 months ago

Yeah, C is definitely it. UDP is for different types of protocols.

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Kallie

2 months ago

I was torn between C and A, but C makes more sense for Modbus.

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Margret

2 months ago

Agreed! Serial is the right choice. It's simple and effective.

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Ressie

2 months ago

I think it's C) Serial. Modbus RTU is all about serial communication.

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Kassandra

2 months ago

Definitely C) Serial. It’s widely used in industrial settings.

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Latricia

2 months ago

I feel confident about that too. It's a classic protocol.

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Wade

3 months ago

Agreed! Serial communication is its backbone.

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Marla

3 months ago

I think it's C) Serial. Modbus RTU is known for that.

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Barabara

3 months ago

C) Serial is correct, no doubt!

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Lucina

3 months ago

Wait, are you sure about that?

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Kimbery

5 months ago

100% agree, it's Serial!

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Ahmed

5 months ago

I thought it was UDP?

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Mirta

5 months ago

It's definitely C) Serial.

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Abel

5 months ago

I thought Modbus was over Ethernet, this is surprising!

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Louvenia

5 months ago

C is correct, but I thought it was outdated.

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Meaghan

5 months ago

Wait, are you sure it's not UDP?

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Josephine

6 months ago

Definitely C) Serial, no doubt about it.

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Lizette

6 months ago

Modbus RTU uses serial communication!

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Amina

6 months ago

I vaguely recall that Modbus RTU is used in serial communication, but I should double-check that before answering.

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Melda

6 months ago

I feel like I might confuse Modbus with something else, but I want to say it's not UDP or ICMP.

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Carlene

6 months ago

I remember practicing a question about Modbus, and I think it was definitely related to serial communication.

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Corazon

6 months ago

I think Modbus RTU uses a serial communication protocol, but I'm not entirely sure.

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