128. 15 . 4 .0
255.255.255.0
256 (254) addresses
128. 15 . 4 .0
255.255.255.128
128 (126) addresses
I Need Half that Number of Addresses !
128. 15 . 4 .0
255.255.255.192
64 (62) addresses
128. 15 . 4 .0
255.255.255.224
32 (30) addresses
128. 15 . 4 .0
255.255.255.240
16 (14) addresses
128. 15 . 4 .0
255.255.255.248
8 (6) addresses
We can do this in either direction and we can keep doing it until we run out of bits
1111 1111 . 1111 1111 . 1111 1111 . 0000 0000
1111 1111 . 1111 1111 . 1111 1111 . 1000 0000
1111 1111 . 1111 1111 . 1111 1111 . 1100 0000
1111 1111 . 1111 1111 . 1111 1111 . 1110 0000
1111 1111 . 1111 1111 . 1111 1111 . 1111 0000
1111 1111 . 1111 1111 . 1111 1111 . 1111 1000
Oh and BTW I am still going easy on you the 1's and 0's do not have to be contiguous