Multicast provides an efficient way to send data to an interested set of receivers to only one copy of data from the source, by letting the intermediate multicast-routers in the network replicate packets to reach multiple receivers based on a group subscription.

Multicast clients (aka receivers) use the Internet Group Management Protocol (IGMP) to propagate membership information from hosts to Multicast enabled routers and PIM to propagate group membership information to Multicast servers via Multicast routers.

config-profile-device-multicast-topology

Multicast support includes:

  • Multicast support on both overlay and underlay
  • Protocol-Independent Multicast - Sparse Mode (PIM-SM) on VCE
  • Internet Group Management Protocol (IGMP) version 2 on VCE
  • Static Rendezvous Point (RP) configuration, where RP is enabled on a 3rd party router.

Configure Multicast Globally

There are two steps to enable and configure Multicast (globally and at the interface level), in which both can be overridden at the Edge Level. The steps below provide instructions on how to enable the Multicast globally.

To configure Multicast globally:

  1. From Configure > Profile > Devices, go to the Multicast Settings area.
  2. If the Multicast Settings button is in the Off position, click the Off button to turn On Multicast Settings.

    The RP Selection is set to Static by default.

    config-profile-device-multicast-settings
  3. In the appropriate textboxes for the RP Selection, type in the RP Address and Multicast Group. (See the table below for a description of RP Address and Multicast Group ).
  4. If applicable, select the Enable PIM on Overlay checkbox and enter the IP Source Address.
  5. Set Advanced Settings, if necessary. Refer to the table that follows for a description of each setting. In the appropriate text boxes, enter PIM Timers for Join Prune Send Interval (default 60 seconds) and Keep Alive Timer (default 60 seconds).

Multicast Settings

The following table describes Multicast settings.

Multicast Setting Description
RP Selection Configure RP for multicast groups. Static RP is the default and supported mechanism in 3.2 release.
Enable PIM on Overlay Enable PIM peering on SD-WAN Overlay, for example when enabled on both branch VCE and hub VCE. Branch VCE and hub VCE will form a PIM peer. By default, the source IP address for the overlays is derived from one of the multicast-enabled underlay interfaces and it is recommended to leave the default. Users can optionally change the source IP by specifying Source IP Address, which will be a virtual address and will be advertised over the overlay automatically.
PIM Timers
Join Prune Send Interval The Join Prune Interval Timer. Default value is 60 seconds.
Keep Alive Timer PIM keep alive timer. Default value is 60 seconds.