Cisco Cisco IOS Software Release 12.0(22)S
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Cisco IOS Release 12.0(22)S
Bidirectional PIM
Feature History
This feature module describes the Bidirectional PIM (bidir-PIM) feature. It includes the following
sections:
sections:
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Feature Overview
Bidir-PIM is a variant of the Protocol Independent Multicast (PIM) suite of routing protocols for IP
multicast. In PIM, packet traffic for a multicast group is routed according to the rules of the mode
configured for that multicast group. The Cisco IOS implementation of PIM supports three modes for a
multicast group:
multicast. In PIM, packet traffic for a multicast group is routed according to the rules of the mode
configured for that multicast group. The Cisco IOS implementation of PIM supports three modes for a
multicast group:
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Bidirectional mode
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Dense mode
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Sparse mode
A router can simultaneously support all three modes or any combination of them for different multicast
groups. In bidirectional mode, traffic is routed only along a bidirectional shared tree that is rooted at the
rendezvous point (RP) for the group. In bidir-PIM, the IP address of the RP acts as the key to having all
routers establish a loop-free spanning tree topology rooted in that IP address. This IP address need not
be a router, but can be any unassigned IP address on a network that is reachable throughout the PIM
domain. Using this technique is the preferred configuration for establishing a redundant RP
configuration for bidir-PIM.
groups. In bidirectional mode, traffic is routed only along a bidirectional shared tree that is rooted at the
rendezvous point (RP) for the group. In bidir-PIM, the IP address of the RP acts as the key to having all
routers establish a loop-free spanning tree topology rooted in that IP address. This IP address need not
be a router, but can be any unassigned IP address on a network that is reachable throughout the PIM
domain. Using this technique is the preferred configuration for establishing a redundant RP
configuration for bidir-PIM.
Release
Modification
12.1(2)T
This feature was introduced.
12.0(18)ST
This feature was integrated into Cisco IOS Release 12.0(18)ST.
12.0(22)S
This feature was integrated into Cisco IOS Release 12.0(22)S.