Cisco Cisco IOS Software Release 12.2(27)SBC
Multicast VPN—IP Multicast Support for MPLS VPNs
Information About Multicast VPN—IP Multicast Support for MPLS VPNs
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Cisco IOS Release: Multiple releases (see the Feature History table)
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Extranet multicast is not supported. Multicast routes cannot be imported or exported between VRFs.
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Multicast VPNs cannot span multiple BGP autonomous systems.
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Cisco 10000 series routers using the PRE-1 and Cisco 12000 series routers do not support
bidirectional PIM. Cisco 10000 series routers using the PRE-2 support bidirectional PIM.
bidirectional PIM. Cisco 10000 series routers using the PRE-2 support bidirectional PIM.
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Cisco 10000 series routers do not support the BGP Multipath Load Sharing for eBGP and iBGP
feature.
feature.
Information About Multicast VPN—IP Multicast Support for
MPLS VPNs
MPLS VPNs
To configure the Multicast VPN—IP Multicast Support for MPLS VPNs feature, you must understand
the following concepts:
the following concepts:
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IP Multicast VPNs
The Multicast VPN feature in Cisco IOS software provides the ability to support the multicast feature
over a Layer 3 VPN. As enterprises extend the reach of their multicast applications, service providers
can accommodate these enterprises over their MPLS core network. IP multicast is used to stream video,
voice, and data to an MPLS VPN network core.
over a Layer 3 VPN. As enterprises extend the reach of their multicast applications, service providers
can accommodate these enterprises over their MPLS core network. IP multicast is used to stream video,
voice, and data to an MPLS VPN network core.
A VPN is network connectivity across a shared infrastructure, such as an Internet service provider (ISP).
Its function is to provide the same policies and performance as a private network, at a reduced cost of
ownership, thus creating many opportunities for cost savings through operations and infrastructure.
Its function is to provide the same policies and performance as a private network, at a reduced cost of
ownership, thus creating many opportunities for cost savings through operations and infrastructure.
Historically, IP in IP generic routing encapsulation (GRE) tunnels was the only way to connect through
a service provider network. Although such tunneled networks tend to have scalability issues, they
represent the only means of passing IP multicast traffic through a VPN.
a service provider network. Although such tunneled networks tend to have scalability issues, they
represent the only means of passing IP multicast traffic through a VPN.
MPLS was derived from tag switching and various other vendor methods of IP-switching support
enhancements in the scalability and performance of IP-routed networks by combining the intelligence
of routing with the high performance of switching. MPLS is now used for VPNs, which is an appropriate
combination because MPLS decouples information used for forwarding of the IP packet (the label) from
the information carried in the IP header.
enhancements in the scalability and performance of IP-routed networks by combining the intelligence
of routing with the high performance of switching. MPLS is now used for VPNs, which is an appropriate
combination because MPLS decouples information used for forwarding of the IP packet (the label) from
the information carried in the IP header.
A Multicast VPN allows an enterprise to transparently interconnect its private network across the
network backbone of a service provider. The use of a Multicast VPN to interconnect an enterprise
network in this way does not change the way that enterprise network is administered, nor does it change
general enterprise connectivity.
network backbone of a service provider. The use of a Multicast VPN to interconnect an enterprise
network in this way does not change the way that enterprise network is administered, nor does it change
general enterprise connectivity.