Help with a subnet address

mileage1969

I'm having trouble with network addressing question. I've been given the task of subnetting an address of 130.10.0.0/24 to provide 32 hosts per subnet. I need to work out the first 10 subnets, then use the fourth subnet and assign the highest address to a router interface. I cannot use subnet zero. So far I've got the correct subnet mask which is 255.255.255.192 but am stuck to work out the address as I don't know how to get 10 subnets when I'm working in multiples of 64.

Empathy

Well you've got the mask figured out correctly, but that's actually a /26, not /24.

since you're borrowing all 8 bits from the 3rd octet, your block size is one in that octet (256-255). So your first 10 networks (not counting subnet zero) will be:

130.10.0.64
130.10.0.128
130.10.0.192
130.10.1.0
130.10.1.64
130.10.1.128
130.10.1.192
130.10.2.0
130.10.2.64
130.10.2.128

The fourth network is 130.10.1.0. Since your block size is 64, your broadcast address will be 130.10.1.63. That makes your last valid host 130.10.1.62.