H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – Multicast
H3C S7500E Series Ethernet Switches Chapter 2 IGMP Snooping Configuration
2-2
Multicast packet transmission
without IGMP Snooping
Source
Multicast router
Host A
Receiver
Host B
Host C
Receiver
Multicast packets
Layer 2 switch
Multicast packet transmission
when IGMP Snooping runs
Source
Multicast router
Host A
Receiver
Host B
Host C
Receiver
Layer 2 switch
Figure 2-1 Before and after IGMP Snooping is enabled on the Layer 2 device
2.1.2 Basic Concepts in IGMP Snooping
I. IGMP Snooping related ports
As shown in Figure 2-2, Router A connects to the multicast source, IGMP Snooping
runs on Switch A and Switch B, Host A and Host C are receiver hosts (namely, multicast
group members).
Router A Switch A
Switch B
Eth1/0/1 Eth1/0/2
Eth1/0/3
Eth1/0/1
Eth1/0/2
Receiver
Receiver
Host A
Host B
Host C
Host D
Source
Multicast packets
Router port
Member port
Figure 2-2 IGMP Snooping related ports
Ports involved in IGMP Snooping, as shown in
Figure 2-2, are described as follows: