Installation guide

Network Infrastructure for EtherNet/IP™
6-73
Infrastructure Application Scenarios
• If workstation and remote I/O performance are affected, a switch with IGMP snooping
should be used. In isolated networks, one of the switches will be required to have the
IGMP query function to manage the multicast process as shown in Figure 6-6.
Figure 6-6 Isolated Network with One Controller and a Main Switch with Query Function.
EXAMPLE 4
Figure 6-7 depicts a “daisy chain” configuration similar to and operating under the same conditions as the
one shown in Figure 6-5.
Figure 6-7 Isolated Network with One Controller and a Daisy Chain Configuration.
Here, each producer establishes one connection with the controller with 10-ms RPIs. Each producer
will generate 100 multicast packets per second and will receive 2300 unwanted multicast packets per
second. The workstation will receive 2400 unwanted multicast packets per second and each switch will
process 2400 multicast packets per second.
Switch 1
P1
Programmable
Controller
Workstation
Switch 2
Switch 3 Switch 4
P6 P7 P12 P13 P18 P19 P24
24-port Layer 3
Switch
Producer 1
Programmable
Controller
Workstation
8-port Switch 1 8-port Switch 4
Producer 6 Producer 19 Producer 24
24 Port Switch
• IGMP Query
•
IGMP Snoo
p
in
g
Switches with IGMP
Snooping