NG-MVPN architecture (mLDP-based)

The following figure illustrates an MVPN architecture that uses mLDP as the provider tunnel for transporting multicast traffic.

Figure 1. NG-MVPN with PIM, IGMP/MLD and mLDP signaling

At the access layer, Central Units (CUs) and Distributed Units (DUs) act as multicast hosts and use MLD for IPv6 group membership signaling. DUs serve as downstream receivers.

Both run a combined MVPN and Routed Virtual Private LAN Service (R-VPLS) stack to integrate Layer 2 and Layer 3 services. These access nodes connect to core routers that act as PE devices, where mLDP trees are originated or joined. Traffic passes through the MPLS core.

Core routers forward multicast streams along mLDP-built P2MP label switched paths, indicated by red arrows. This implementation eliminates the need for PIM in the core. E-LER (Egress Label Edge Router) PEs connect to the multicast source and inject traffic into the MVPN domain, initiating tree establishment toward the receivers.