H3C Technologies H3C S3100 Series Switches - Manual (Page 240)

Operation Manual – Multicast
H3C S3100-52P Ethernet Switch Chapter 2 IGMP Snooping Configuration
2-3
Packet normally
Timeout action
Timer Setting received before
on the switch
timeout
Query response
timer
Query response
timeout time
IGMP report
message
Remove the port
from the member
port list of the
multicast group.
II. Layer 2 multicast with IGMP Snooping
The switch runs IGMP Snooping to listen to IGMP messages and map the host, the port
corresponding to the host, and the corresponding multicast MAC address.
Figure 2-2
IGMP Snooping implementation
To implement Layer 2 multicast, the switch processes four different types of IGMP
messages it received, as shown in Table 2-3.
Table 2-3
IGMP Snooping messages
Mes
sage
Sen
der
Recei
ver
Purpo
se
Switch action
If yes, reset the aging
timer of the router port
IGM
P
gene
ral
quer
y
mess
age
Mult
icast
rout
er
and
mult
icast
swit
ch
Multic
ast
memb
er
switch
and
host
Query
if the
multica
st
groups
contain
any
membe
r
Check if the message
comes from the original
router port
If not, notify the
multicast router that a
member is in a
multicast group and
start the aging timer for
the router port