HP 3500YL - Manual (Page 70)

PIM-DM (Dense Mode)
PIM-DM Operation
8212zl #1
8212zl #2
ProCurve
8212zl #3
8212zl #4
Other
Multicast
Router
Other
Multicast
Router
Indicates Paths Requiring
Periodic Flood-Prune Cycles
for a Given Multicast Group
These multicast routers do
not have the state refresh
feature and thus require
periodic flood-prune
cycles to advertise active
multicast group. In this
case it may be better to
group these routers on the
same multicast tree to
avoid the additional flood/
prune cycles on the routers
that do support state
refresh.
These multicast switches support
the state refresh feature but must
handle periodic flood-prune cycles
for the downstream routers that
lack this feature.
These multicast switches support
the state refresh feature and do not
require periodic flood-prune cycles
for a given multicast group, which
frees up bandwidth for other uses.
Video
Server
Video
Server
Video
Server
Figure 3-2. Example of Bandwidth Conservation in Switches with PIM-DM State Refresh
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