84 • Fieldbus CommunicationETHERNETWAGO-I/O-SYSTEM 750ETHERNET TCP/IP• Class B: (Net-ID: Byte1 - Byte2, Host-ID: Byte3 - Byte4)e.g.: 181 . 16 . 232 . 2210110101 00010000 11101000 0001011010 Net-ID Host-IDThe 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 alwaysbetween 128 and 191.• Class C: (Net-ID: Byte1 - Byte3, Host-ID: Byte4)e.g.: 201 . 16 . 232 . 2211000101 00010000 11101000 00010110110 Net-ID Host-IDThe 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 alwaysbetween 192 and 223.Additional network classes (D, E) are only used for special tasks.Key dataAddress range of the Possible number ofsubnetwork networks Subscribers per networkClass A 1.XXX.XXX.XXX -126.XXX.XXX.XXX127(2 7)Ca. 16 Million(2 24)Class B 128.000.XXX.XXX -191.255.XXX.XXXCa. 16 thousand(2 14)Ca 65 thousand(2 16)Class C 192.000.000.XXX -223.255.255.XXXCa. 2 million(2 21)254(2 8)Each WAGO ETHERNET (programmable) fieldbus coupler or controller canbe easily assigned an IP address via the implemented BootP protocol. Forsmall internal networks we recommend selecting a network address fromClass C.AttentionNever set all bits to equal 0 or 1 in one byte (byte = 0 or 255). These arereserved for special functions and may not be allocated. Therefore, the address10.0.10.10 may not be used due to the 0 in the second byte.
