subnetting help

mpca1

Hey,

found this site using google, and by far has a lot of good information. I am practicing my subnetting, and came across this question, and im having a hard time getting the answer.

The IP address space of 128.107.7.0/24 has been allocated for all devices on this network. All
devices must use the same subnet mask and all subnets are usable.
Which subnet mask is required to apply the allocated address space to the configuration that is
shown?

any ideas how to tackle this?

cheers

mpca1

I think I might of figured it out,

/24 so we know that 8 bits are left for the host.
32-24= 8

2^n - 2 = how many hosts we need.
2^8 - 2 = 6, so we need 6 host bits



if we write out

255 | 255 | 1 1 1 1 1 1 1 1 | 1 1 0 0 0 0 0 0 |

/24 + 2 = /26 which ends up being 255.255.255.192

am I right? if anyone can confirm this?

dynamik

Is that the entire question? It doesn't specify how many hosts you need per subnet or anything like that? What is the "configuration that is shown" that it mentions at the end? Is there a diagram?

r_durant

Yea, I'm with dynamik...Is there a diagram or something, the question did state "...the configuration that is shown?"

shednik

Yea I think there is something missing there??

Netstudent

I think the question is trying to get you to figure out what a /24 is. IN which case it would be 255.255.255.0


That would be the subnet mask entered for all the hosts in that range. You may have overcomplicated the question.

But it does say 'Configuration that is shown" so who knows.