The subnet mask for a particular network is 255.255.31.0.
Which of the following IP address belongs to this network?
- 172.57.88,62 & 126.96.36.199
- 10.35.28.2 & 10.35.29.4
- 188.8.131.52 & 184.108.40.206
- 220.127.116.11 & 18.104.22.168
Little bit confuse about 3rd octet of SM ( i.e .31 ) But got the point that 5 bit was hired from 3rd octet for subnetting.
The principle : convert the dotted-quad IP addresses and mask to 32-bit unsigned integers and AND each address with the mask. If the results are the same, they're in the same subnet.
By using above principle Ans is D.
But Can I do it directly ?
- By looking at SM it is clear that , it belongs to class B.
- Option A and C are 2 different networks.( there 2nd octet is different i.e. 172.57 and 172.56 and 191.203 and 191.234 )
- Option B is Class A network.( so cant be the answer)
- Option D is class B network , and its 1st two octet are also same i.e. 128.8 and 128.8 so now no problem to apply above principle to final check.
Can I think like this before applying principle ? ( just to save time )