Terminology for Rosen MVPN

PIM

Protocol Independent Multicast. A multicast routing protocol.

Reachable unicast routes are the basis of PIM forwarding. PIM uses the existing unicast routing information to perform RPF check on multicast packets, to create multicast routing entries, and to set up an MDT.

SPT

Shortest path tree. A multicast tree with a multicast source at the root and group members at the leaves. An SPT applies to PIM-DM, PIM-SM, and PIM-SSM.

share-group

A multicast group that all VPN instances on PEs in the same multicast domain join.

Currently, one VPN instance can be configured with only one share-group, so one VPN instance can join only one MD.

share-MDT

An MDT that is set up when PIM C-instances on PEs join a share-group. A share-MDT transmits PIM protocol packets and low-rate data packets in a VPN to other PEs within the same VPN. A share-MDT is considered as a multicast tunnel (MT) within an MD.

MTI

Multicast tunnel interface. An outbound or inbound interface of an MT or MD. An MTI connects a local PE to a remote PE to implement communication between two PEs.

MTIs are used by PEs to define transmission processes on MTs and set up communication channels between public network instances and VPN instances. An MTI connects a PE to an MT, so that the PE is connected to a shared network segment. MTIs are also used by PEs to set up PIM neighbor relationships for VPN instances in the same MD.

switch-group

A group that PEs that have multicast VPN receivers join after a share-MT is set.

switch-MDT

Switch-multicast distribution tree. An on-demand MDT that is set up after PEs that have multicast VPN receivers join a switch-group. A switch-MDT prevents multicast data packets from being transmitted to unnecessary PEs and transmits high-rate data packets to other PEs in the same VPN.

AS

autonomous system

ASBR

autonomous system boundary router

PIM-SM

Protocol Independent Multicast-Sparse Mode

RP

rendezvous point