Infomax Computer Academy

Suppose computers A and B have IP addresses 10.105.1.113 and 10.105.1.91 respectively and they both use the same net mask N. Which of the values of N given below should not be used if A and B should belong to the same network?




Solution
D. 255.255.255.224



Explanation

 Given: 10.105.1.113 and 10.105.1.91
When these are in same network, then AND with netmask give the address of same ID otherwise these are in different class in these only AND with 255.255.255.224 are in different class
This is 96 and 64. Then these are different ID means 10.105.1.96 and 10.105.1.64 are different ID. So this is not in same network.
Alternately

When we do the similar operation with 2nd IP
it gives 10.105.1.64
Here, it gives different IP
but for the rest it gives same IP.