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PIM Sparse-Mode (PIM-SM)
Protocol-independent multicast sparse-mode (PIM-SM) is supported on Dell Networking OS.
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.
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
.
• 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.
• Dell Networking OS reduces the number of control messages sent between multicast routers by
bundling Join and Prune requests in the same message.
• Dell Networking OS supports PIM-SM on physical, virtual local area network (VLAN), and port-channel
interfaces.
NOTE: Multicast routing is supported across default and non-default VRFs.
Protocol Overview
PIM-SM initially uses unidirectional shared trees to forward multicast traffic; that is, all multicast traffic
must flow only from the rendezvous point (RP) to the receivers.
After a receiver receives traffic from the RP, PM-SM switches to SPT to forward multicast traffic. Every
multicast group has an RP and a unidirectional shared tree (group-specific shared tree).
Requesting Multicast Traffic
A host requesting multicast traffic for a particular group sends an Internet group management protocol
(IGMP) Join message to its gateway router.
The gateway router is then responsible for joining the shared tree to the RP (RPT) so that the host can
receive the requested traffic.
1.
After receiving an IGMP Join message, the receiver gateway router (last-hop DR) creates a (*,G) entry
in its multicast routing table for the requested group. The interface on which the join message was
received becomes the outgoing interface associated with the (*,G) entry.
2.
The last-hop DR sends a PIM Join message to the RP. All routers along the way, including the RP,
create an (*,G) entry in their multicast routing table, and the interface on which the message was
received becomes the outgoing interface associated with the (*,G) entry. This process constructs an
RPT branch to the RP.
PIM Sparse-Mode (PIM-SM)
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Содержание Z9000
Страница 1: ...Dell Configuration Guide for the Z9000 System 9 7 0 0 ...
Страница 80: ...grub reboot 80 Management ...
Страница 128: ... 0 Te 1 1 Te 1 2 rx Flow N A N A 128 Access Control Lists ACLs ...
Страница 436: ...Figure 50 Inspecting Configuration of LAG 10 on ALPHA 436 Link Aggregation Control Protocol LACP ...
Страница 439: ...Figure 52 Inspecting a LAG Port on BRAVO Using the show interface Command Link Aggregation Control Protocol LACP 439 ...
Страница 440: ...Figure 53 Inspecting LAG 10 Using the show interfaces port channel Command 440 Link Aggregation Control Protocol LACP ...
Страница 491: ...Figure 70 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 491 ...
Страница 492: ...Figure 71 Configuring PIM in Multiple Routing Domains 492 Multicast Source Discovery Protocol MSDP ...
Страница 496: ...Figure 73 MSDP Default Peer Scenario 1 496 Multicast Source Discovery Protocol MSDP ...
Страница 497: ...Figure 74 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 497 ...
Страница 498: ...Figure 75 MSDP Default Peer Scenario 3 498 Multicast Source Discovery Protocol MSDP ...
Страница 760: ...Figure 100 Single and Double Tag TPID Match 760 Service Provider Bridging ...
Страница 761: ...Figure 101 Single and Double Tag First byte TPID Match Service Provider Bridging 761 ...