Figure 5-2 shows the format of a typical IGMP snooping version 1 message that is received after an IGMP snooping query in a multicast group has been completed.
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Figure 5-2 Format of an IGMP Version 1 Message
When IGMP snooping is running on a CoreBuilder® 5000 hub, it allows multicast traffic to ports where:
■IGMP Report packets for that multicast group have been observed.
■Multicast routing protocols have been observed.
Figure 5-3 shows a typical multicast packet path after snooping has occurred.
Multicast
Router
Host 3
Host 1
Host 3 sends a |
| CoreBuilder® 5000 Hub |
Multicast Packet |
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