CompTIA Network+ Network+ OSI Model and Data Encapsulation 2

Question 1

A network engineer is troubleshooting a connectivity issue and finds that MAC addresses are not being resolved correctly. Which OSI layer is responsible for MAC address resolution?

Accepted Answer

Data Link layer

Answer

The Data Link layer (Layer 2) handles MAC addresses and frame delivery on the local network segment.

Question 2

During data encapsulation, what term describes the data unit at the Transport layer?

Accepted Answer

Segment

Answer

At the Transport layer (Layer 4), the data unit is called a segment (for TCP) or datagram (for UDP).

Question 3

Which OSI layer is responsible for establishing, managing, and terminating sessions between applications?

Accepted Answer

Session layer

Answer

The Session layer (Layer 5) manages dialog control and session establishment, maintenance, and termination.

Question 4

A packet is received with a TTL value of 0. Which OSI layer processes TTL and causes the packet to be discarded?

Accepted Answer

Network layer

Answer

The Network layer (Layer 3) processes TTL; when it reaches 0, the router discards the packet and sends an ICMP Time Exceeded message.

Question 5

Which layer of the OSI model converts data into a format suitable for transmission, including encryption and compression?

Accepted Answer

Presentation layer

Answer

The Presentation layer (Layer 6) handles data translation, encryption, and compression to ensure data is in a usable format.

CompTIA Practice Test

CompTIA Practice Test

CompTIA Network+ Network+ OSI Model and Data Encapsulation 2