Configuring L2 Multicast Features 703
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Configuring L2 Multicast Features
This chapter describes the layer 2 multicast features on the PowerConnect 
7000 Series switches. The features this chapter describes include bridge 
multicast filtering, Internet Group Management Protocol (IGMP) snooping, 
Multicast Listener Discovery (MLD) snooping, and Multicast VLAN 
Registration (MVR).
The topics covered in this chapter include:
• L2 Multicast Overview
• Snooping Switch Restrictions
• Default L2 Multicast Values
• Configuring L2 Multicast Features (Web)
• Configuring L2 Multicast Features (CLI)
• Case Study on a Real-World Network Topology
L2 Multicast Overview
Multicast traffic is traffic from one source that has multiple destinations. The 
L2 multicast features on the switch help control network flooding of Ethernet 
multicast and IP multicast traffic by keeping track of multicast group 
membership. It is essential that a multicast router be connected to a 
PowerConnect layer 2 multicast switch for IGMP/MLD snooping to operate 
properly. The presence of a multicast router allows the snooping switch to 
relay IGMP reports to the router and to forward multicast data sources to the 
multicast router as well as restrict flooding of multicast sources in a VLAN.
What Are the Multicast Bridging Features?
The PowerConnect 7000 Series switches support multicast filtering and 
multicast flooding. For multicast traffic, the switch uses a database called the 
Layer 2 Multicast Forwarding Database (MFDB) to make forwarding