# OSI Layer

 Question 1
In the following pairs of OSI protocol layer/sub-layer and its functionality, the INCORRECT pair is
 A Network layer and Routing B Data Link Layer and Bit synchronization C Transport layer and End-to-end process communication D Medium Access Control sub-layer and Channel sharing
GATE CSE 2014 SET-3   Computer Network
Question 1 Explanation:
 Question 2
An IP machine Q has a path to another IP machine H via three IP routers R1, R2, and R3.
Q---R1---R2---R3---H
H acts as an HTTP server, and Q connects to H via HTTP and downloads a file. Session layer encryption is used, with DES as the shared key encryption protocol. Consider the following four pieces of information:
[I2] The TCP port numbers at Q and H
[I3] The IP addresses of Q and H
Which of I1, I2, I3, and I4 can an intruder learn through sniffing at R2 alone?
 A Only I1 and I2 B Only I1 C Only I2 and I3 D Only I3 and I4
GATE CSE 2014 SET-2   Computer Network
Question 2 Explanation:
 Question 3
Match the following:
 (P) SMTP     (1) Application layer
(Q) BGP      (2) Transport layer
(R) TCP      (3) Data link layer
(S) PPP      (4) Network layer
(5) Physical layer 
 A P - 2 Q - 1 R - 3 S - 5 B P - 1 Q - 4 R - 2 S - 3 C P - 1 Q - 4 R - 2 S - 5 D P - 2 Q - 4 R - 1 S - 3
GATE CSE 2007   Computer Network
Question 3 Explanation:
 Question 4
Choose the best matching between Group 1 and Group 2
$\begin{array}{|l|l|}\hline \textbf{Group-1} & \textbf{Group-2} \\\hline \text{P. Data link layer} & \text{1. Ensures reliable transport of data over a physical point-}\\ & \text{to-point link} \\\hline \text{Q. Network layer} & \text{2. Encodes/decodes data for physical transmission} \\\hline \text{R. Transport layer} & \text{3. Allows end-to-end communication between two }\\ & \text{processes} \\\hline \text{} & \text{4. Routes data from one network node to the next} \\\hline \end{array}$
 A P - 1, Q - 4, R - 3 B P- 2, Q - 4, R - 1 C P - 2, Q - 3, R - 1 D P-1, Q - 3, R - 2
GATE CSE 2004   Computer Network
Question 4 Explanation:
There are 4 questions to complete.

### 2 thoughts on “OSI Layer”

1. In Question no. 4 Group 2 point no. 4 Missing pease update