SEW-Eurodrive DFE32B PROFINET IO, Manual

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Manual – DFE32B Fieldbus Interface PROFINET IO
4
TCP/IP addressing and subnetworks
Assembly and Installation Notes
4.7 TCP/IP addressing and subnetworks
Introduction The settings for the address of the IP protocol are made using the following parameters:
• IP address
• Subnet mask
• Standard gateway
The addressing mechanisms and subdivision of the IP networks into subnets are ex-
plained in this chapter to help you set the parameters correctly.
IP address The IP address is a 32-bit value that uniquely identifies a node in the network. An IP ad-
dress is represented by four decimal numbers separated by decimal points.
Example: 192.168.10.4
Each decimal number stands for one byte (= 8 bits) of the address and can also be rep-
resented using binary code (
→ following table).
The IP address comprises a network address and a node address ( → following table).
The part of the IP address that denotes the network and the part that identifies the node
is determined by the network class and the subnet mask.
Node addresses cannot consist of only zeros or ones (binary) because they represent
the network itself or a broadcast address.
Network classes The first byte of the IP address determines the network class and as such represents
the division into network addresses and node addresses.
This rough division is not sufficient for a number of networks. They also use an explicit,
adjustable subnet mask.
Subnet mask A subnet mask is used to divide the network classes into even finer sections. Like the
IP address, the subnetwork mask is represented by four decimal numbers separated by
decimal points. Every decimal number stands for one byte.
Example: 255.255.255.128
Each decimal number stands for one byte (= 8 bits) of the subnetwork mask and can
also be represented using binary code (
→ following table).
If you compare the IP addresses with the subnet masks, you see that in the binary rep-
resentation of the subnet mask all ones determine the network address and all the zeros
Byte 1 Byte 2 Byte 3 Byte 4
11000000 . 10101000 . 00001010 . 00000100
Network address Node address
192.168.10 4
Value range
Network class
Complete network address
(Example)
Meaning
Byte 1
0 ... 127 A 10.1.22.3 10 = Network address
1.22.3 = node address
128 ... 191 B 172.16.52.4 172.16 = Network address
52.4 = node address
192 ... 223 C 192.168.10.4 192.168.10 = Network address
4 = node address
Byte 1 Byte 2 Byte 3 Byte 4
11111111 . 11111111 . 11111111 . 10000000