GATE CSE 2025 | Set 1 | Question: 6

Question

Identify the ONE CORRECT matching between the OSI layers and their corresponding functionalities as shown.

$$\begin{array}{|l|l|} \hline & \textbf{OSI Layers} && \textbf{Functionalities} \\ \hline (a) & \text{Network Layer} & (I) & \text{Packet Routing} \\ \hline (b) & \text{Transport Layer} & (II) & \text{Framing and error handling} \\ \hline (c) & \text{Datalink layer} & (III) & \text{Host to host communication} \\ \hline \end{array}$$

• A. $\text{(a)-(I), (b)-(II), (c)-(III)}$
• B. $\text{(a)-(I), (b)-(III), (c)-(II)}$
• C. $\text{(a)-(II), (b)-(I), (c)-(III)}$
• D. $\text{(a)-(III), (b)-(II), (c)-(I)}$

Comments

Answer = B,,,https://correctbrain.com/buy/

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none of the options are correct, since host to host is done by network layer , not by the transport layer

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@Arjun sir but transport layer is responsible for Process to process delivery and host to host is dont by network layer

Answer 1

(B) a-i, b-iii, c-ii

Network layer is responsible for Packet Routing
Transport layer is responsible for Host to host communication (or Port to Port)
Data Link Layer is responsible for framing and error handling

Comments

how network layer? @LewisHamilton

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Anything with an IP address is a HOST. and IP provides the facility for HOST to HOST delivery.. that is WHOLE purpose of IP
moreover you can see forouzan it is mentioned there

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@Dev_Ops did you find any resource?

Answer 2

Packet Routing is the responsibility of Network Layer. (a) → I. 

Framing and error (bit level) handling is the responsibility of Data Link Layer. Hence, (c) → II 

Host to Host communication (end to end Communication) is the responsibility of Transport Layer. Hence, (b) → III 

Hence, Option (b) is correct.

Answer 3

Functionalities 

◼ Packet Routing is performed by the Network Layer within the Network Protocol stack. Therefore (a) Network Layer → (i) Packet Routing

◼ Host-to-Host communication is managed by the Transport Layer. Therefore (b) Transport Layer → (iii) Host to Host Communication

◼ Framing and Error handling are managed at the Data Link Layer in a Network Protocol stack. Therefore (c) Datalink Layer → (ii) Framing and Error Handling 

So the answer is B. (a) - (i), (b) - (iii), (c) - (ii)

Answer 4

Network Layer (Host-to-Host): This layer is responsible for host-to-host delivery of individual packets (datagrams) from the original source to the final destination.

Transport Layer (Process-to-Process): This layer is responsible for process-to-process delivery—the delivery of a message from one running application process on one host to another on the destination host.

which means none of the options are correct

Can refer forouzan book for the layers in OSI Model