Classes
    Ranges
				octets
	         netid  hostid   masks
A - 0-127      1     2-4     255.0.0.0
B - 128-191    1,2   3,4     255.255.0.0
C - 192-223    1-3   4       255.255.255.0
D - 224-239
E - 240-255


Number  Number   Netmasks 
IP      subnets
address
  2      128     255.255.255.254
  4       64     255.255.255.252
  8       32     255.255.255.248
 16       16     255.255.255.240
 32        8     255.255.255.224
 64        4     255.255.255.192
128        2     255.255.255.128