Rockwell Automation 1734-AENT POINT I/O EtherNet/IP Adapter Module - Manual (Page 33)

Publication 1734-UM011D-EN-P - May 2011
Configure the Adapter for Your EtherNet/IP Network 17
IP Address
The IP address identifies each node on the IP network (or system of
connected networks). Each TCP/IP node on a network (including the
1734-AENT adapter) must have a unique IP address.
The IP address is 32 bits long and has a net ID part and Host ID part.
Networks are classified A, B, C, (or other). The class of the network
determines how an IP address is formatted.
You can distinguish the class of the IP address from the first integer in its
dotted-decimal IP address as follows:
Each node on the same physical network must have an IP address of the same
class and must have the same net ID. Each node on the same network must
have a different Host ID thus giving it a unique IP address.
IP addresses are written as four decimal integers (0…255) separated by periods
where each integer gives the value of one byte of the IP address.
Gateway Address
This section applies to multi-network systems. If you have a single network
system, refer to the next section.
The Gateway Address is the default address of a network. It provides a single
domain name and point of entry to the site. Gateways connect individual
physical networks into a system of networks.
Class A
Class B
Class C
Net ID
Net ID
Net ID Host ID
Host ID
Host ID
0
0
0
10
0
110
7 8
31
31
31
15 16
23 24
Range of first integer Class Range of first integer Class
0 …127 A 192 … 223 C
128 …191 B 224 … 255 other
EXAMPLE
For example, the 32-bit IP address:
10000000 00000001 00000000 00000001 is written as
128.1.0.1