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Interview Question
- Thread starter WANDr
- Start date
DanielBowen
Technical User
I think what they mean is how many class C networks will be available if you use a /22 mask (supernetting)
Using a /22 mask you can get 4 class C networks/1022 hosts
by shortening the mask by 2 bits, you are creating three more networks, hence 4 class C's
Its a badly worded question because a /24 and /22 address are two totally different things.
Hope this helps
Using a /22 mask you can get 4 class C networks/1022 hosts
by shortening the mask by 2 bits, you are creating three more networks, hence 4 class C's
Its a badly worded question because a /24 and /22 address are two totally different things.
Hope this helps
Taraporter
Technical User
If I am understanding your question correctly, they want to know how many /24 networks can you get from a /22. So, if I put this into a working example it would be:
You are Company A with a network ID of 10.10.16.0/22. Without subnetting, you have 1 network with 1022 hosts.
11111111.11111111.11111100.00000000 = 255.255.252.0
However, you want to subnet this down to be a /24 network. That is borrowing 2 bits from the host side. Borrowing 2 bits gives you 4 subnets.
11111111.11111111.11111111.00000000 - 255.255.255.0
And now there are 254 hosts per subnet (8 bits left over as opposed to 10).
Your available subnets with this new mask would be:
10.10.16.0/24
10.10.17.0/24
10.10.18.0/24
10.10.19.0/24
You will not be able to go higher then 10.10.19.255 because that would cut into someone else's subnet. (10.10.19.255 being a braodcast is not assignable anyways)
This is my answer if I understand the wording of your question. Supernetting (the opposite of subnetting) would be if you have multiple subnets and want them to be advertised as 1 line instead of 10 (random number). For example:
You have a network consisting of 200.140.0.0/28. That gives you 16 subnets. Instead of advertising 200.140.0.16/28; 200.140.0.32/28; 200.140.0.48/28; 200.140.0.64/28; etc.... you could advertise 200.140.0.0/24. (Notice the amount of subnets had decresed.
I hope this helps you and didn't confuse you.
Tara
You are Company A with a network ID of 10.10.16.0/22. Without subnetting, you have 1 network with 1022 hosts.
11111111.11111111.11111100.00000000 = 255.255.252.0
However, you want to subnet this down to be a /24 network. That is borrowing 2 bits from the host side. Borrowing 2 bits gives you 4 subnets.
11111111.11111111.11111111.00000000 - 255.255.255.0
And now there are 254 hosts per subnet (8 bits left over as opposed to 10).
Your available subnets with this new mask would be:
10.10.16.0/24
10.10.17.0/24
10.10.18.0/24
10.10.19.0/24
You will not be able to go higher then 10.10.19.255 because that would cut into someone else's subnet. (10.10.19.255 being a braodcast is not assignable anyways)
This is my answer if I understand the wording of your question. Supernetting (the opposite of subnetting) would be if you have multiple subnets and want them to be advertised as 1 line instead of 10 (random number). For example:
You have a network consisting of 200.140.0.0/28. That gives you 16 subnets. Instead of advertising 200.140.0.16/28; 200.140.0.32/28; 200.140.0.48/28; 200.140.0.64/28; etc.... you could advertise 200.140.0.0/24. (Notice the amount of subnets had decresed.
I hope this helps you and didn't confuse you.
Tara
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