Bidir; Ssm; Rpf Routes For Multicast; Igmp And Mld - Cisco Nexus 7000 Series Configuration Manual

Overview
attached to each source that is an active sender. The ASM mode requires an RP for a group range. An RP can
be configured statically or learned dynamically by the Auto-RP or BSR group-to-RP discovery protocols. If
an RP is learned and is not known to be a Bidir-RP, the group operates in ASM mode.
The ASM mode is the default mode when you configure RPs.

Bidir

Bidirectional shared trees (Bidir) is a PIM mode that, like the ASM mode, builds a shared tree between
receivers and the RP, but does not support switching over to a source tree when a new receiver is added to a
group. In the Bidir mode, the router that is connected to a receiver is called the designated forwarder because
multicast data can be forwarded directly from the designated router (DR) to the receiver without first going
to the RP. The Bidir mode requires that you configure an RP.
The Bidir mode can reduce the amount of resources required on a router when there are many multicast sources
and can continue to operate whether or not the RP is operational or connected.

SSM

Source-Specific Multicast (SSM) is a PIM mode that builds a source tree that originates at the designated
router on the LAN segment that receives a request to join a multicast source. Source trees are built by sending
PIM join messages in the direction of the source. The SSM mode does not require you to configure RPs.
The SSM mode allows receivers to connect to sources outside the PIM domain.

RPF Routes for Multicast

You can configure static multicast RPF routes to override what the unicast routing table uses. This feature is
used when the multicast topology is different than the unicast topology.

IGMP and MLD

By default, the Internet Group Management Protocol (IGMP) for PIM and Multicast Listener Discovery
(MLD) for PIM6 are running on the system.
IGMP and MLD protocols are used by hosts that want to receive multicast data to request membership in
multicast groups. Once the group membership is established, multicast data for the group is directed to the
LAN segment of the requesting host.
You can configure IGMPv2 or IGMPv3 on an interface. You will usually configure IGMPv3 to support SSM
mode. By default, the software enables IGMPv2.
You can configure MLDv1 or MLDv2 on an interface. You will usually configure MLDv2 to support SSM
mode. By default, the software enables MLDv2.

IGMP Snooping

IGMP snooping is a feature that limits multicast traffic on VLANs to the subset of ports that have known
receivers. By examining (snooping) IGMP membership report messages from interested hosts, multicast traffic
is sent only to VLAN ports that interested hosts reside on. By default, IGMP snooping is running on the
system.
Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide
Bidir
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