The Multicast Manager sends a streamlined copy of its multicast topology—instances of the MulticastService, MulticastGroup, MulticastTree, MulticastSource, MulticastRedundancyGroup, MSDPSession, IGMPNetwork, and PIMHop classes—to the Global Manager. The Global Manager combines this topology with the underlying transport network topology received from the IP Availability Manager.

The Global Console presents the topology information in a variety of dynamically updated formats that show the status of the multicast and network elements and their many relationships. One of those formats is the topology map, which is a graphical representation of the topology that shows multicast connectivity. The map shows the multicast connectivity between sources, routers and receiving networks. Devices that perform special functionality for multicast are labeled; for example, DR indicates a designated router.

Launching the Multicast map

The Multicast map can be launched by selecting Multicast Map on the right-click menu:
  • From an object in the Topology Browser
  • From an icon in a map
The Multicast map can be launched from the following classes of objects:
  • MulticastTree
  • MulticastGroup
  • MulticastSource
  • MulticastService
  • IGMPNetwork
  • Router
  • Switch

After the Multicast map is launched

When the map opens, it is centered on the object that it was launched from. Initially, the map will show the objects that are one hop away from the starting object (except when launched from a MulticastTree object when all the elements of the tree are shown).

To expand the map, select Expand Node from the right-click menu for objects that have an expansion “plus” icon to their lower right.

Connections in the Multicast map

Following describes the connections between icons in the Multicast map represent different relationships or objects depending on the two endpoints.

Start End Arrow Description
MulticastSource Router or Switch Sources relationship between the MulticastSource and the Router or Switch
Router or Switch Router or Switch Represents the PIMHop between MulticastService instances running on each device for one MulticastGroup
Router or Switch GMPNetwork ReportedByNetwork relationship between the MulticastService running on Router or Switch and the IGMPNetwork
Icons for devices that perform specialized roles in multicast networks have a label displayed next to them in the Multicast map. Following table shows the roles for which labels are displayed.
Multicast role for device Label
Designated router DR
Rendezvous point RP
Bootstrap router BSR

Highlighting a multicast group

When a map shows the paths for more than one multicast group, you can highlight the path for one specific group by selecting it from the combo box above the top left corner of the map. The connections for the selected group are the highlighted using an animated highlight feature which indicates the data flow along the connections.