Block sizes

Hi,

How would I go by working out the block size for a ip address which shows a different value in the third octet?

1.1.128.1
1.1.130.178
1.1.129.174
1.1.130.101
1.1.134.169
1.1.135.174

Thanks

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Comments

ehnde

lon21 wrote: »

Hi,

How would I go by working out the block size for a ip address which shows a different value in the third octet?

1.1.128.1
1.1.130.178
1.1.129.174
1.1.130.101
1.1.134.169
1.1.135.174

Thanks

You can't - not without knowing how many network bits you have. The 1.0.0.0 network has over 16 million addresses.

If you're talking about subnets ranging in the 3rd octet, we're talking about multiple different subnet masks. There is a big difference between 255.255.128.0 and 255.255.224.0

luisYme

hi-
if the question is to find a subnet mask that would create a network which would encompass all of those subnets then this would work:

255.255.248.0

so, 1.1.128.0/21

that's a range from 1.1.128.0 - 1.1.135.255

i love subnetting

Ltat42a

lon21 wrote: »

Hi,

How would I go by working out the block size for a ip address which shows a different value in the third octet?

1.1.128.1
1.1.130.178
1.1.129.174
1.1.130.101
1.1.134.169
1.1.135.174

Thanks

Starting at 1.1.128.1 - 1.1.135.x all seem to fit into a block size of 8. What block size mask equals 8? 248.
So your mask would be 255.255.248.0
The entire range would be 1.1.128.0 - 1.1.135.255,
the next subnet would be 1.1.136.0.