10.0.0.1 16 8 10.0.0.1/16 Host Address 0A000001 167772161 00001010.00000000.00000000.00000001 255.255.0.0 16 0.0.255.255 10.0.0.0 10.0.255.255 10.0.0.1 - 10.0.255.254 10.0.0.1 10.0.255.254 256 10.0.0.0 - 10.255.0.0 65536 65534 A Class A (first octet 0-127) B Class B (/16) Address class is A from the first octet. Shop-floor slang: Class A=/8, Class B=/16, Class C=/24. This /16 is called Class B. private