Allied Telesis AT-9724TS PIM-DM Interface Configuration, PIM-DM Configuration, Probe Interval

The following fields can be set:
	Parameter	Description
	Interface Name	Displays the name of the IP interface for which DVMRP is to be configured.This must be a previously defined IP
	IP Address	interface.
		Displays the IP address corresponding to the IP Interface name entered above.
	Neighbor Timeout Interval	This field allows an entry between 1 and 65,535 seconds and defines the time period for DVMRP will hold
(1-65535)
	Probe Interval (1-65535)	Neighbor Router reports before issuing poison route messages.The default is 35 seconds.
		This field allows an entry between 1 and 65,535 seconds and defines the interval between ‘probes’.The default
	Metric (1-31)	is 10.
		This field allows an entry between 1 and 31 and defines the route cost for the IP interface.The DVMRP route
		cost is a relative number that represents the real cost of using this route in the construction of a multicast
	State	delivery tree. It is similar to, but not defined as, the hop count in RIP.The default cost is 1.
		This field can be toggled between Enabled and Disabled and enables or disables DVMRP for the IP interface.
		The default is Disabled.

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 > IP Multicast Routing Protocol > PIM > PIM-DM Configuration.This will give the user access to the following screen:

Figure 6- 135. PIM DM Global Settings window

Use the pull down menu, choose Enabled, and click Apply to set the PIM-DM function on the Switch.

Allied Telesyn AT-9724TS High-Density Layer 3 Stackable Gigabit Ethernet Switch 131