Technical data

Fieldbus Communication • 179
ETHERNET
WAGO-I/O-SYSTEM 750
BACnet/IP Controller
Class A: (Net-ID: Byte1, Host-ID: Byte2 - Byte4)
e.g.:
101 . 16 . 232 . 22
01100101 00010000 11101000 00010110
0 Net-ID Host-ID
The highest bit in Class A networks is always ‘0’.
Meaning the highest byte can be in a range of
’0 0000000’ to ‘0 1111111’.
Therefore, the address range of a Class A network in the first byte is always
between 0 and 127.
Class B: (Net-ID: Byte1 - Byte2, Host-ID: Byte3 - Byte4)
e.g.:
181 . 16 . 232 . 22
10110101 00010000 11101000 00010110
10 Net-ID Host-ID
The highest bits in Class B networks are always ’10’.
Meaning the highest byte can be in a range of
’10 000000’ to ‘10 111111’.
Therefore, the address range of Class B networks in the first byte is always
between 128 and 191.
Class C: (Net-ID: Byte1 - Byte3, Host-ID: Byte4)
e.g.:
201 . 16 . 232 . 22
11000101 00010000 11101000 00010110
110 Net-ID Host-ID
The highest bits in Class C networks are always ‘110’.
Meaning the highest byte can be in a range of
’110 00000’ to ‘110 11111’.
Therefore, the address range of Class C networks in the first byte is always
between 192 and 223.
Additional network classes (D, E) are only used for special tasks.
Key data
Address range of the Possible number of
subnetwork networks Subscribers per network
Class A
1.XXX.XXX.XXX -
126.XXX.XXX.XXX
127
(2
7
)
Ca. 16 Million
(2
24
)
Class B
128.000.XXX.XXX -
191.255.XXX.XXX
Ca. 16 thousand
(2
14
)
Ca 65 thousand
(2
16
)
Class C
192.000.000.XXX -
223.255.255.XXX
Ca. 2 million
(2
21
)
254
(2
8
)
Each WAGO ETHERNET (programmable) fieldbus coupler or controller can
be easily assigned an IP address via the implemented BootP protocol. For
small internal networks we recommend selecting a network address from
Class C.