Networking - Subnetting - Discussion
Discussion Forum : Subnetting - Subnetting (Q.No. 5)
5.
You need to subnet a network that has 5 subnets, each with at least 16 hosts. Which classful subnet mask would you use?
Answer: Option
Explanation:
You need 5 subnets, each with at least 16 hosts. The mask 255.255.255.240 provides 16 subnets with 14 hosts-this will not work. The mask 255.255.255.224 provides 8 subnets, each with 30 hosts. This is the best answer.
Discussion:
26 comments Page 3 of 3.
Manikandan said:
8 years ago
I need formula 2^16=32 value of network.
So I taken 128.64.32. value mention after another 0.0.0.0.0 calculate 128+64+32=224.
Ans 255.255.255.224.
So I taken 128.64.32. value mention after another 0.0.0.0.0 calculate 128+64+32=224.
Ans 255.255.255.224.
Czar said:
6 years ago
5 subnets 16 hosts
First, you have to meet the number of the host which is 16. By borrowing 4 bits we will meet 16 hosts but there will be no room for the network and broadcast address so we will use 5 bits that has 32 hosts. Using the 2^5 -2 will give us 30 which satisfy our required number of hosts.
Secondly, we will use the formula an actual number of network = 32 (by default) minus no. of borrowed bits so 32-5 equals 27.
Our new subnet mask is /27 which is equivalent to 255.255.255.224.
First, you have to meet the number of the host which is 16. By borrowing 4 bits we will meet 16 hosts but there will be no room for the network and broadcast address so we will use 5 bits that has 32 hosts. Using the 2^5 -2 will give us 30 which satisfy our required number of hosts.
Secondly, we will use the formula an actual number of network = 32 (by default) minus no. of borrowed bits so 32-5 equals 27.
Our new subnet mask is /27 which is equivalent to 255.255.255.224.
(3)
Pollob basak said:
4 years ago
4 subnets, each with at least 20 hosts. Which subnet mask? Please explain about it.
Jayden said:
4 years ago
16 hosts < 32, 32 = 2^5, so it takes 5 bits, and each subnet has 30 hosts.
32 " 5 = 27, it means the subnet-mask has /27 bits.
5 subnets < 8, 8 = 2^3,
therefore, 27 " 3 = 24 bits,
= 255.255.255.0.
8 subnets x 32 IPs " 2 = 254, the answer should be 255.255.255.0.
For example class c IP, 192.168.1.1/24 with subnet-mask 255.255.255.224.
32 " 5 = 27, it means the subnet-mask has /27 bits.
5 subnets < 8, 8 = 2^3,
therefore, 27 " 3 = 24 bits,
= 255.255.255.0.
8 subnets x 32 IPs " 2 = 254, the answer should be 255.255.255.0.
For example class c IP, 192.168.1.1/24 with subnet-mask 255.255.255.224.
Abhishek Jha said:
3 years ago
16 hosts < 32, 32 = 2^5, so it takes 5 bits, and each subnet has 30 hosts.
32 " 5 = 27, it means the subnet-mask has /27 bits.
5 subnets < 8, 8 = 2^3,
therefore, 27 " 3 = 24 bits,
= 255.255.255.0.
8 subnets x 32 IPs " 2 = 254, the answer should be 255.255.255.0.
For example class c IP, 192.168.1.1/24 with subnet-mask 255.255.255.224.
32 " 5 = 27, it means the subnet-mask has /27 bits.
5 subnets < 8, 8 = 2^3,
therefore, 27 " 3 = 24 bits,
= 255.255.255.0.
8 subnets x 32 IPs " 2 = 254, the answer should be 255.255.255.0.
For example class c IP, 192.168.1.1/24 with subnet-mask 255.255.255.224.
Nabahani kisiwa said:
3 days ago
Good, Thanks all.
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