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Port mirroring – D-Link DES-3326 User Manual

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DES-3326 Layer 3 Fast Ethernet Switch User’s Guide

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.

The following fields can be set:

Parameter

Description

Interface Name

Allows the entry of the name of the
IP interface for which PIM-DM is to
be configured. This must be a
previously defined IP interface.

IP Address

Displays the IP address for the IP
interface named above.

Hello Interval <30

>

This field allows an entry of between
1 and 18724 seconds and
determines the interval between
sending Hello packets to other
routers on the network. The default
is 30 seconds.

Join/Prune
Interval <
60 >

This field allows an entry of between
0 and 18724 seconds. The default is
60 seconds.

State <Disabled>

This field can be toggled between
Enabled and Disabled using the pull-
down menu, and is used to enable or
disable PIM-DM for the IP interface.
The default is Disabled.

Port Mirroring

To configure a port for port mirroring:

Click the Mirroring link and then the Target Port Selection link:

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