H3C Technologies H3C S7500E Series Switches - Manual (Page 28)

1-11
The high-order 16 bits of an IPv6 multicast MAC address are 0x3333, and the low-order 32 bits are
the low-order 32 bits of a multicast IPv6 address. Figure 1-7 shows an example of mapping an IPv6
multicast address, FF1E::F30E:101, to a MAC address.
Figure 1-7 An example of IPv6-to-MAC address mapping
Multicast Protocols
z Generally, we refer to IP multicast working at the network layer as Layer 3 multicast and the
corresponding multicast protocols as Layer 3 multicast protocols, which include IGMP/MLD,
PIM/IPv6 PIM, MSDP, and MBGP/IPv6 MBGP; we refer to IP multicast working at the data link
layer as Layer 2 multicast and the corresponding multicast protocols as Layer 2 multicast
protocols, which include IGMP Snooping/MLD Snooping, and multicast VLAN/IPv6 multicast
VLAN.
z IGMP Snooping, IGMP, multicast VLAN, PIM, MSDP, and MBGP are for IPv4, MLD Snooping,
MLD, IPv6 multicast VLAN, IPv6 PIM, and IPv6 MBGP are for IPv6.
z This section provides only general descriptions about applications and functions of the Layer 2
and Layer 3 multicast protocols in a network. For details of these protocols, refer to the related
configuration manuals in the IP Multicast Configuration Guide.
Layer 3 multicast protocols
Layer 3 multicast protocols include multicast group management protocols and multicast routing
protocols. Figure 1-8 describes where these multicast protocols are in a network.