Waters Network Systems
User’s Manual
Page 17
GSM-2116 and GSM-2124
Class A:
Address is less than 126.255.255.255. There are a total of 126 networks can be defined
because the address 0.0.0.0 is reserved for default route and 127.0.0.0/8 is reserved for
loopback function.
0
Class B:
IP address range between 128.0.0.0 and 191.255.255.255. Each class B network has a 16-bit
network prefix followed 16-bit host address. There are 16,384 (2^14)/16 networks able to be
defined with a maximum of 65534 (2^16 –2) hosts per network.
10
Class C:
IP address range between 192.0.0.0 and 223.255.255.255. Each class C network has a 24-bit
network prefix followed 8-bit host address. There are 2,097,152 (2^21)/24 networks able to be
defined with a maximum of 254 (2^8 –2) hosts per network.
110
Class D and E:
Class D is a class with first 4 MSB (most significance bit) set to 1-1-1-0 and is used for IP
Multicast. See also RFC 1112. Class E is a class with first 4 MSB set to 1-1-1-1 and is used for
IP broadcast.
According to IANA (internet assigned numbers authority), there are three specific IP address
blocks reserved and able to be used for extending internal networks. This is referred to as
Private IP address and listed below:
Class A
10.0.0.0 --- 10.255.255.255
Class B
172.16.0.0 --- 172.31.255.255
Class C
192.168.0.0 --- 192.168.255.255
Please refer to RFC 1597 and RFC 1466 for more information.
Subnet mask:
Bit # 0 1 7 8 31
Network address Host address
Bit # 01 2 15 16 31
Network address Host address
Bit # 0 1 2 3 23 24 31
Network address Host
