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Table of Contents 
1 Multicast Overview····································································································································1-1 
Multicast Overview··································································································································1-1 
Information Transmission in the Unicast Mode···············································································1-1 
Information Transmission in the Broadcast Mode···········································································1-2 
Information Transmission in the Multicast Mode·············································································1-2 
Roles in Multicast ····························································································································1-3 
Advantages and Applications of Multicast·······················································································1-4 
Multicast Models ·····································································································································1-4 
Multicast Architecture······························································································································1-5 
1.1.1 Multicast Protocols ·················································································································1-8 
Multicast Packet Forwarding Mechanism ·····························································································1-10 
Implementation of the RPF Mechanism ························································································1-10 
RPF Check ····································································································································1-11 
2 IGMP Snooping Configuration ·················································································································2-1 
IGMP Snooping Overview·······················································································································2-1 
Principle of IGMP Snooping ············································································································2-1 
Basic Concepts in IGMP Snooping ·································································································2-1 
Work Mechanism of IGMP Snooping ······························································································2-2 
IGMP Snooping Configuration ················································································································2-4 
1.1.1 Enabling IGMP Snooping·······································································································2-5 
Configuring the Version of IGMP Snooping ····················································································2-5 
Configuring Timers ··························································································································2-6 
Configuring Fast Leave Processing ································································································2-6 
Configuring a Multicast Group Filter································································································2-7 
Configuring the Maximum Number of Multicast Groups on a Port··················································2-8 
Configuring IGMP Querier···············································································································2-9 
Suppressing Flooding of Unknown Multicast Traffic in a VLAN····················································2-10 
Configuring Static Member Port for a Multicast Group··································································2-10 
Configuring a Static Router Port····································································································2-11 
Configuring a Port as a Simulated Group Member ·······································································2-12 
Configuring a VLAN Tag for Query Messages··············································································2-13 
Configuring Multicast VLAN ··········································································································2-13 
Displaying and Maintaining IGMP Snooping·························································································2-15 
IGMP Snooping Configuration Examples ·····························································································2-15 
Configuring IGMP Snooping··········································································································2-15 
Configuring Multicast VLAN ··········································································································2-17 
Troubleshooting IGMP Snooping··········································································································2-20 
3 Common Multicast Configuration············································································································3-1 
Common Multicast Configuration············································································································3-1 
Configuring a Multicast MAC Address Entry ···················································································3-1 
Configuring Dropping Unknown Multicast Packets ·········································································3-2 
Displaying Common Multicast Configuration ··························································································3-2