An MPLS service provider is offering a standard EoMPLS-based VPLS service to Customer A, providing Layer 2 connectivity between a central site and approximately 100 remote sites. Customer A wants to u

EoMPLS VPLS treats multicast as BUM traffic and floods it across all pseudowires to every site, consuming 100 Mb/s of replicated bandwidth per site and making the design extremely unscalable at 100 remote sites.

Replicating multicast on P routers does not eliminate the flooding behavior of VPLS; traffic would still be sent to all sites regardless of group membership, providing no scalability benefit.

Layer 3 MVPN uses PIM-based Multicast Distribution Trees (MDTs) to route multicast traffic only to sites that have joined specific groups, rather than flooding to all 100 remote sites. This avoids the BUM (Broadcast, Unknown unicast, Multicast) flooding behavior inherent in VPLS, where 20 groups at 5 Mb/s each would be replicated across every pseudowire. MVPN is the industry-standard scalable design for carrying multicast traffic across MPLS VPN networks.

GRE tunnels create point-to-point overlays that require the source to individually replicate each stream per tunnel, providing no multicast-awareness and no scalability improvement over standard VPLS flooding.