Administrator Guide
PIM Sparse-Mode (PIM-SM)
Dell Networking OS supports protocol-independent multicast sparse-mode (PIM-SM).
PIM-SM is a multicast protocol that forwards multicast traffic to a subnet only after a request using a PIM Join
message; this behavior is the opposite of PIM-Dense mode, which forwards multicast traffic to all subnets
until a request to stop.
Topics:
• Implementation Information
• Protocol Overview
• Configuring PIM-SM
• Enable PIM-SM
• Configuring S,G Expiry Timers
• Configuring a Static Rendezvous Point
• Configuring a Designated Router
• Creating Multicast Boundaries and Domains
• Enabling PIM-SM Graceful Restart
Implementation Information
Be aware of the following PIM-SM implementation information.
• The Dell Networking implementation of PIM-SM is based on IETF Internet Draft draft-ietf-pim-sm-v2-
new-05.
• FN IOM supports a maximum of 31 PIM interfaces and 2K multicast entries including (*,G), and (S,G)
entries. There is no limit on the number of PIM neighbors FN IOM can have.
• The SPT-Threshold is zero, which means that the last-hop designated router (DR) joins the shortest path
tree (SPT) to the source after receiving the first multicast packet.
• The Dell Networking operating system (OS) reduces the number of control messages sent between
multicast routers by bundling Join and Prune requests in the same message.
• The Dell Networking OS supports PIM-SM on physical, virtual local area network (VLAN), and port-
channel interfaces.
• The Dell Networking OS supports 2000 IPv6 multicast forwarding entries, with up to 128 PIM-source-
specific multicast (SSM) neighbors/interfaces.
• IPv6 Multicast is not supported on synchronous optical network technologies (SONET) interfaces.
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