OSI & TCP/IP Model
Question
Which OSI layer does UDP operate in?
A. Layer 1
B. Layer 2
C. Layer 3
D. Layer 4
E. Layer 5
Answer: D
Explanation
User Datagram Protocol (UDP) and Transmission Control Protocol (TCP) operate in Transport Layer (Layer 4). UDP provides a connectionless (a communication session between hosts is not established before exchanging data), unreliable transport service. UDP is often used in real-time services such as voice or video.
Question
Which layer in the TCP/IP model is responsible for sending packets to the destination?
A. Application Layer
B. Session Layer
C. Internet Layer
D. Network Layer
E. Transport Layer
Answer: C
Explanation
The Internet Layer of the TCP/IP model is similar to the Network Layer (Layer 3) of the OSI Model so it is responsible for sending packets to the destination.
Question
Which term is used to describe data in Layer 4 of the OSI model?
A. Packet
B. Frame
C. Bit
D. Segment
E. LSU
Answer: D
Explanation
Layer 4 of the OSI Model is the Transport Layer and the unit of the data in this layer is called “Segment”. In Layer 3 (Network Layer) it is called “Packet”, in Layer 2 (Data Link Layer) it is called “Frame” and in Layer 1 (Physical Layer) it is called “Bit”.
Question
PC1 discarded a frame because it was corrupted. Which OSI layer is responsible for this elimination?
A. Layer 4
B. Layer 3
C. Layer 2
D. Layer 1
E. Layer 5
Answer: C
Explanation
When the unit of a data is called “Frame”, we will know it is proceeding in the Data Link Layer (Layer 2).
Question
What are the OSI layer names from Layer 3 to Layer 5? (Choose three)
A. Application
B. Transport
C. Network
D. Presentation
E. Session
Answer: B C E
Question
What are the layer names of the TCP/IP model?
A. Network, Application, Data Link, Physical
B. Application, Transport, Internet, Data Link
C. Internet, Application, Network Interface, Transport
D. Application, Network, Internet, Transport
E. Data Link, Network, Physical, Transport
Answer: C
Explanation
The name of the TCP/IP model and OSI model is shown below:
Question
Which of the following protocols use TCP? (Choose three)
A. FTP
B. SNMP
C. TFTP
D. SMTP
E. DNS
Answer: A D E
Explanation
Note: DNS uses both TCP and UDP
Question
Which of the following protocols operate over UDP? (Choose two)
A. HTTP
B. SNMP
C. SQL
D. Telnet
E. TFTP
Answer: B E
Question
Which transport protocol requires a three-way handshake before establishing a connection?
A. UDP
B. TCP
C. IP
D. ARP
E. Gracious ARP
Answer: B