Administrator Guide

Table Of Contents
Layer-2 Multicast Features 867
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Layer-2 Multicast Features
Dell Networking N1500, N2000, N3000, and N4000 Series Switches
This chapter describes the layer-2 (L2) multicast features on the Dell
Networking N-Series switches. The features this chapter describes include
bridge multicast flooding and forwarding, 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 Dell
Networking 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.
Multicast Flooding and Forwarding
Flooding behavior is to send incoming multicast packets to all ports in the
VLAN other than the ingress port. Forwarding behavior is to send incoming
multicast packets to selected ports in the VLAN. Forwarding behavior is