Cisco Nexus 7000 Series Configuration Manual page 23

Overview
Figure 6: PIM Domains in an IPv4 Network
• The lines with arrows show the path of the multicast data through the network. The multicast data
originates from the sources at hosts A and D.
• The dashed line connects routers B and F, which are Multicast Source Discovery Protocol (MSDP) peers.
MSDP supports the discovery of multicast sources in other PIM domains.
• Hosts B and C receive multicast data by using the Internet Group Management Protocol (IGMP) to
advertise requests to join a multicast group.
• Routers A, C, and D are designated routers (DRs). When more than one router is connected to a LAN
segment, such as C and E, the PIM software chooses one router to be the DR so that only one router is
responsible for putting multicast data on the segment
Router B is the rendezvous point (RP) for one PIM domain and router F is the RP for the other PIM domain.
The RP provides a common point for connecting sources and receivers within a PIM domain.
This figure shows two PIM6 domains in an IPv6 network. In an IPv6 network, receivers that want to receive
multicast data use the Multicast Listener Discovery (MLD) protocol to advertise requests to join a multicast
group. MSDP, which allows for discovery of multicast sources in other PIM domains, is not supported for
Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide
Cisco NX-OS PIM and PIM6
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