EtherNet/IP Network Communication

The

EtherNet/IP™

network offers control, configuration, and data collection services by layering the Common Industrial Protocol (

CIP™

) over the standard Internet protocols, such as TCP/IP and UDP. This combination of standards provides full support for information data exchange and control applications.

The controller supports 10 Mbps/100 Mbps/1 Gbps port speeds and provides double data rate (DDR) capability across the

ControlLogix®

backplane.

Network performance in the controller system is optimal if the 1 Gbps speed is used. However, legacy Ethernet devices do not support the 1 Gbps speed. Instead, they support a maximum rate of 100 Mbps.

The difference in maximum link speeds impacts your controller system and, in some applications, restricts you from using the 1 Gbps link speeds on a controller.

When you design a controller system and consider using the 1 Gbps rate on the controller, remember the following:

You can use the 1 Gbps speed on the controller port when all network devices support 1 Gbps.
When switches are used in a star topology, configure the controller ports to use Auto Negotiate.

You can use the 1 Gbps speed on the controller port when some network devices support a maximum link speed of 100 Mbps. However, the controller must be connected to those devices through a managed switch.

Do not mix 1 Gbps and 100 Mbps port speeds within one DLR network or linear network.
IMPORTANT:
To help prevent bursts of traffic and DLR traffic reversal due to a ring break, do not use different speeds on device ports in the same
EtherNet/IP™
network without a managed switch.
If you use two or more of these components with a legacy Ethernet device in a ring or linear topology, set all devices to a fixed speed of 100 Mbps and full-duplex:
ControlLogix®
or
GuardLogix®
controllers
Compact GuardLogix®
5380 controllers
5069 communication adapters
5094 communication adapters