Configuring PIM Tunnels

PIM tunnels are enabled automatically on routers that have a tunnel PIC and on which you enable PIM sparse mode. You do not need to configure the tunnel interface.

PIM tunnels are unidirectional.

In PIM sparse mode, the first-hop router encapsulates packets destined for the rendezvous point (RP) router. The packets are encapsulated with a unicast header and are forwarded through a unicast tunnel to the RP. The RP then de-encapsulates the packets and transmits them through its multicast tree. To perform the encapsulation and de-encapsulation, the first-hop and RP routers must be equipped with Tunnel PICs.

The JUNOS software creates two interfaces to handle PIM tunnels:

• pe—Encapsulates packets destined for the RP. This interface is present on the first-hop router.
• pd—De-encapsulates packets at the RP. This interface is present on the RP.

  Note: The pe and pd interfaces do not support class-of-service (CoS) configurations.