Installation guide

Network Infrastructure for EtherNet/IP™
6-79
Infrastructure Application Scenarios
6.5 Application Summary
Characterizing network traffic on EtherNet/IP helps determine which type of network will provide the
best balance of performance and installed cost. The recommendations provided here are aimed at
optimizing network—and ultimately control system—performance. They are based on the use of switches
with the increasing levels of functionality needed to handle more devices with more traffic and short,
implicit I/O control response times. Routers are used to selectively link these systems with enterprise or
plant networks without disrupting any of the networks. Table 6-1 summarizes the relative degree that the
application considerations discussed here are factors in the four general system types.
Table 6-1 Application Factors for System Types
System Type
Isolated System
Single Controller
Isolated System
Multiple Controllers
Enterprise
Network
Connected
Enterprise
Network
Integrated
Application Factors
Isolation of control
system vs. plant
network traffic and
prevention of
multicast traffic
overload of control
devices
Use of lower-cost
unmanaged switches
possible.
Added traffic design
calculations if
unmanaged switches
are used.
Requires managed
(IGMP snooping)
switches.
VLAN functionality
may optionally be
needed.
PC with 2 NICs
possible; use of a
CIP gateway
preferred.
Requires managed
(IGMP snooping)
switches.
VLAN functionality
may optionally be
needed.
Requires managed
switches with
IGMP snooping
and VLAN
functionality.
Will likely require
Layer 3 switches or
routers at the join
points.
Appendix A Recommendations for Ethernet Switches in EtherNet/IP Systems summarizes the required and
desirable switch features for the various system types described here.