CompTIA Network+ Network+ OSI Model and Data Encapsulation 3

Question 1

Which OSI layer is responsible for flow control and error recovery using mechanisms like windowing and acknowledgments?

Accepted Answer

Transport layer

Answer

The Transport layer (Layer 4) provides flow control through windowing and ensures reliable delivery via acknowledgments and retransmission.

Question 2

A frame is received with a bad FCS value. At which OSI layer is this error detected?

Accepted Answer

Data Link layer

Answer

The Frame Check Sequence (FCS) is a Data Link layer field used to detect transmission errors in received frames.

Question 3

Which of the following best describes the role of the Physical layer in the OSI model?

Accepted Answer

Converts data to electrical, optical, or radio signals

Answer

The Physical layer (Layer 1) defines the transmission of raw bits over a physical medium as electrical, optical, or wireless signals.

Question 4

An application developer needs to ensure data is formatted consistently for exchange between different systems. Which OSI layer addresses this concern?

Accepted Answer

Presentation layer

Answer

The Presentation layer (Layer 6) handles data syntax and semantics, ensuring data is in a common format regardless of the source system.

Question 5

What does a switch primarily use to make forwarding decisions at OSI Layer 2?

Accepted Answer

MAC addresses

Answer

Switches operate at the Data Link layer and use MAC address tables to forward frames to the correct port.

CompTIA Practice Test

CompTIA Practice Test

CompTIA Network+ Network+ OSI Model and Data Encapsulation 3