D-Link TM DES-6500, Manual

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DES-6500 Chassis-based Layer 3 Ethernet Switch Manual
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PIM-DM Interface Configuration
The Protocol Independent Multicast - Dense Mode (PIM-DM) protocol should be used in networks with a low delay (low
latency) and high bandwidth as PIM-DM is optimized to guarantee delivery of multicast packets, not to reduce overhead.
The PIM-DM multicast routing protocol is assumes that all downstream routers want to receive multicast messages and
relies upon explicit prune messages from downstream routers to remove branches from the multicast delivery tree that do
not contain multicast group members.
PIM-DM has no explicit ‘join’ messages. It relies upon periodic flooding of multicast messages to all interfaces and then
either waiting for a timer to expire (the
Join/Prune Interval ) or for the downstream routers to transmit explicit ‘prune’
messages indicating that there are no multicast members on their respective branches. PIM-DM then removes these
branches (‘prunes’ them) from the multicast delivery tree.
Because a member of a pruned branch of a multicast delivery tree may want to join a multicast delivery group (at some
point in the future), the protocol periodically removes the ‘prune’ information from its database and floods multicast
messages to all interfaces on that branch. The interval for removing ‘prune’ information is the
Join/Prune Interval .
PIM-DM Configuration
To enable PIM-DM globally on the Switch, go to Configuration > Layer 3 IP Networking > IP Multicast Routing
Protocol > PIM > PIM-DM Configuration . This will give the user access to the following screen:
Figure 6- 146. PIM-DM Global Settings window
Use the pull down menu, choose Enabled , and click Apply to set the PIM-DM function on the Switch.
PIM-DM Interface Configuration
To view the PIM-DM Table , click Configuration > IP Multicast Routing Protocol > PIM > PIM-DM Interface
Settings. This window allows the PIM-DM to be configured for each IP interface defined on the Switch. Each IP interface
configured on the Switch is displayed in the below PIM-DM Interface Settings dialog box. To configure PIM-DM for a
particular interface, click the corresponding hyperlink for that IP interface. This will open the PIM-DM Interface Settings
window:
Figure 6- 147. PIM-DM Interface Settings window
To view the configuration window for a specific entry, click its hyperlinked name, revealing the following window.