3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring PIM-DM 575
■ If so, the DR sends a subscribe message for channel subscription hop by hop
toward the multicast source S. An (Include S, G) is created on all routers on the
path from the DR to the source. Thus, an SPT is built in the network, with the
source S as its root and receivers as its leaves. This SPT is the transmission
channel in PIM-SSM.
■ If not, the PIM-SM process is followed: the DR needs to send a (*, G) join
message to the RP, and a multicast source registration process is needed.
n
In PIM-SSM, the "channel" concept is used to refer to a multicast group, and the
"channel subscription" concept is used to refer to a join message.
Protocols and Standards PIM-related specifications are as follows:
■ RFC 2362: Protocol Independent Multicast-sparse Mode (PIM-SM): Protocol
Specification
■ RFC 3973: Protocol Independent Multicast-Dense Mode (PIM-DM): Protocol
Specification(Revised)
■ draft-ietf-pim-sm-v2-new-06: Protocol Independent Multicast-Sparse Mode
(PIM-SM)
■ draft-ietf-pim-dm-new-v2-02: Protocol Independent Multicast-Dense Mode
(PIM-DM)
■ draft-ietf-pim-v2-dm-03: Protocol Independent Multicast Version 2 Dense
Mode Specification
■ draft-ietf-pim-sm-bsr-03: Bootstrap Router (BSR) Mechanism for PIM Sparse
Mode
■ draft-ietf-ssm-arch-02: Source-Specific Multicast for IP
■ draft-ietf-ssm-overview-04: An Overview of Source-Specific Multicast (SSM)
Configuring PIM-DM
PIM-DM Configuration
Task L is t
Complete these tasks to configure PIM-DM:
Configuration
Prerequisites
Before configuring PIM-DM, complete the following task:
■ Configure any unicast routing protocol so that all devices in the domain are
interoperable at the network layer.
Before configuring PIM-DM, prepare the following data:
■ The interval between state refresh messages
■ Minimum time to wait before receiving a new refresh message
Task Remarks
“Enabling PIM-DM” on page 576 Required
“Enabling State Refresh” on page 576 Optional
“Configuring State Refresh Parameters” on page 576 Optional
“Configuring PIM-DM Graft Retry Period” on page 577 Optional
“Configuring PIM Common Information” on page 587 Optional