VLSM with Class B

theNoob

Hi Guys,

I am just starting out and learning about VLSM, I am confident when I have to design IP Scheme with class c but class b gets to me.. I was wondering if someone can help me with the problem below? or even give me some tips on where I could began or if they have any resources or videos that I can watch that may help me understand VLSM better?

IP Address: 172.16.0.0 /24

IT Students: 180
Engineering: 72
Mathematics: 66
Aviation: 60
Chemistry: 60
Biology: 20
Geography: 20
Physics: 9

How do i figure out an IP scheme for this? I mean except for IT students every other hosts fits in the Class C.

Jon_Cisco

If your being asked to use vlsm then your instructor wants to see you split up the network space. Not just fit it in.

Are you sure the subnet mask is correct for the example?
IP Address: 172.16.0.0 /24
172.16.0.1 - 172.16.0.255 is all you have to work with?


Just looking quickly you need to figure out your minimum blocks.

IT Students: 180 /24
Engineering: 72 /25
Mathematics: 66 /25
Aviation: 60 /26
Chemistry: 60 /26
Biology: 20 /27
Geography: 20 /27
Physics: 9 /28

Show us what you got so far and well try to help you through it.

Good Luck!

mikeybinec

Basically. VLSM allows you to tailor the subnet mask to your needs. In the olden days, or with RIP ver1, you had to use classful sizes. I like to call them equal sizes for each network. If you had three routers connected to each other, the link from router 1 to router 2 would realistically only need 2 hosts, but with classful definitions, you might have 62 hosts per network. So VLSM allows you to make network sizes that are realistic. It appears to me you might have to go to a /23 instead of a /24. Go from your largest block size to your smallest like Jon has outlined