Rockwell Automation Ethernet Design Considerations Reference Manual User Manual
Page 82
 
82
Rockwell Automation Publication ENET-RM002C-EN-P - May 2013
Chapter 5
Predict System Performance
Part Two: Predict Maximum input or Output Times for 
CIP Connections
A CIP connection is an efficient communication path used for high 
performance. The following are basic types of CIP connections:
•
Rack-optimized
•
Input or output data
•
Produced tag
A CIP connection is bi-directional. During every RPI, each end of a connection 
initiates a packet of information. A packet of information represents a 
connection.
The type of data packet produced by each end of the connection depends on the 
connection type as described below.
To predict the maximum input (I/O to controller) or output (controller to I/O) 
times for CIP connections, complete the following steps.
1.
Estimate the maximum time intervals for each CIP connection types 
used in the control system.
2.
If necessary, modify your system to get more throughput by performing 
one or more of the adjustments described under 
step 5
on
page 81
.
3.
If you have made modifications, verify that the modified system works by 
recounting the connections and recalculating the packet rate capacity 
loading.
Connection Type
Scanner
Adapter
Producer 
Controller
Consumer 
Controller
Rack-optimized
Output data
Input data
N/A
N/A
Input data
Heartbeat
Input data
N/A
N/A
Output data
Output data
Output data echo
N/A
N/A
Produced tag
N/A
N/A
Tag data
Heartbeat