Configuring Layer 2 Multicast
Layer 2 Multicast
Configuration Guide
267
Demonstrated as below:
Figure 1-1
IGMP Snooping
Source
Multicast router
Layer 2 switch
Host A
Host B
Host C
Receiver
Receiver
Multicast packets transmission with
IGMP Snooping
Source
Multicast router
Layer 2 switch
Host A
Host B
Host C
Receiver
Receiver
Multicast packets transmission
without IGMP Snooping
Multicast packets
1.2 Supported Layer 2 Multicast Protocols
Layer 2 Multicast protocol for IPv4: IGMP Snooping
On the Layer 2 device, IGMP Snooping transmits data on demand on data link layer by
analyzing IGMP packets between Layer 3 devices and users, to build and maintain Layer 2
multicast forwarding table.
Layer 2 Multicast protocol for IPv6: MLD Snooping
On the Layer 2 device, MLD Snooping (Multicast Listener Discovery Snooping) transmits
data on demand on data link layer by analyzing IGMP packets between Layer 3 devices and
users, to build and maintain Layer 2 multicast forwarding table.