PLANET VC-810S - Manual (Page 66)

User’s Manual of VC-810S / VC-810S48
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The Multicast table is combined with a Layer 2 MAC table with maximum of 8k entries. For a
given multicast entry, the valid port member bit will auto age out after 300 seconds if the port
does not receive a corresponding group address IGMP report packet.
Enabling IGMP Snooping allows the ports to detect IGMP queries and report packets and manage IP multicast traffic
through the switch. IGMP have three fundamental types of message as follows:
Message Description
Query
A message sent from the querier (IGMP router or switch) asking for a response
from each host belonging to the multicast group.
Report
A message sent by a host to the querier to indicate that the host wants to be or is a
member of a given group indicated in the report message.
Leave Group
A message sent by a host to the querier to indicate that the host has quit to be a
member of a specific multicast group.