Ericsson ECN330, User Manual

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Configuring the ECN330-switch
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• SPT Threshold – Prevents the last-hop PIM-SM router from switching
to Shortest Path Source Tree (SPT) mode. (Default: Disabled)
• The default path for packets from a multicast source to a receiver is
through the RP. However, the path through the RP is not always the
shortest path. Therefore, the router uses the RP to forward only the
first packet from a new multicast group to its receivers. Afterwards,
it calculates the shortest path tree (SPT) directly between the
receiver and source, and then uses the SPT to send all subsequent
packets from the source to the receiver instead of using the shared
tree.
• Enable the SPT threshold to force the router to use the shared tree
for all multicast groups, or just for the specified multicast groups.
• SPT Group – The IP address for a multicast group which must use the
shared tree. If a group address is not specified, the shared tree is used
for all multicast groups.
• SPT Group Mask – Subnet mask that is used for the group address.
Web – Click Routing Protocol, PIM-SM, Global Settings. Modify any of the
protocol parameters as required, and click Apply.
Figure 229 PIM-SM Global Settings