Cisco CCNA OSI and TCP/IP Models 2

Question 1

A network engineer needs to troubleshoot why two hosts can ping each other but cannot establish a Telnet session. Which OSI layer should be investigated first?

Accepted Answer

Layer 4 - Transport

Answer

Ping operates at Layer 3, so if ping works, Layers 1-3 are functional; Telnet failures point to Layer 4 (TCP port 23) or above.

Question 2

Which TCP/IP model layer is responsible for logical addressing and routing between networks?

Accepted Answer

Internet

Answer

The Internet layer of the TCP/IP model handles IP addressing and routing, equivalent to the OSI Network layer.

Question 3

What is the term for the data unit at the OSI Data Link layer?

Accepted Answer

Frame

Answer

The Data Link layer (Layer 2) encapsulates data into frames, which include MAC addressing and error detection (FCS).

Question 4

Which OSI layer converts data between formats such as encryption, compression, and character encoding?

Accepted Answer

Presentation (Layer 6)

Answer

The Presentation layer (Layer 6) handles data translation, encryption/decryption, and compression between the application and network.

Question 5

In which scenario does the OSI Session layer play a critical role?

Accepted Answer

Managing dialog control between two applications in a video conference

Answer

The Session layer (Layer 5) establishes, manages, and terminates communication sessions, including dialog control for applications like video conferencing.

Cisco CCNA Practice Test

Cisco CCNA Practice Test

Cisco CCNA OSI and TCP/IP Models 2