MVPN is a standards-based feature that transmits IPv4 multicast traffic across an MPLS VPN cloud. MVPN on Catalyst 6500 series switches uses the existing PFC hardware support for IPv4 multicast traffic to forward multicast traffic over VPNs at wire speeds. MVPN adds support for IPv4 multicast traffic over Layer 3 IPv4 VPNs to the existing IPv4 unicast support.
MVPN routes and forwards multicast packets for each individual VPN routing and forwarding (VRF) instance, as well as transmitting the multicast packets through VPN tunnels across the service provider backbone.
MVPN is an alternative to IP-in-IP generic route encapsulation (GRE) tunnels. GRE tunnels are not a readily scalable solution and they are limited in the granularity they provide to customers.
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