UGC NET CSE | September 2013 | Part 3 | Question: 12

Question

Given the IP address 201.14.78.65 and the subset mask 255.255.255.224. What is the subset address?

• A. 201.14.78.32
• B. 201.14.78.64
• C. 201.14.78.65
• D. 201.14.78.224

Answer 1

Answer : 201.14.78.64

At every router basically we have  3 entries in a routing table 

1. Network Id / Subnet address

2. Subnet Mask

3 .Interface

So with the help of these we can figure out where to send a packet.

IP address 201.14.78.65                   subset mask 255.255.255.224

IP address	11111111.11111111.11111111.11100000
Subnet Mask	11001001.00001110.01001110.01000001
Subnet address	11001001.00001110.01001110.01000000
	201 . 14 . 78 . 64

It is a Bitwise ANDing in above operation.

Answer 2

        201.14.78.65               = 201.14.78.01000001

        255.255.255.224        =  255.255.255.11100000

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                                                       201.14.78.01000000 = 201.14.78.64