1-11 MPLS L3VPN ConfigurationWhen configuring MPLS L3VPN, go to these sections for information you are interested in:z MPLS L3VPN Overviewz MPLS L3VPN Configuration Task Listz Displaying and Maintaining MPLS L3VPNz MPLS L3VPN Configuration Examplesz The term router in this document refers to a router in a generic sense or a Layer 3 switch.z This chapter covers only introduction to and configuration of MPLS L3VPN. For information aboutMPLS basics, BGP, and VPN, refer to the relevant manuals or volumes.MPLS L3VPN OverviewThis section covers these topics:z Introduction to MPLS L3VPNz MPLS L3VPN Conceptsz MPLS L3VPN Packet Forwardingz MPLS L3VPN Networking Schemesz MPLS L3VPN Routing Information Advertisementz Multi-AS VPNz Carrier’s Carrierz Nested VPNz HoVPNz OSPF VPN Extensionz BGP AS Number SubstitutionIntroduction to MPLS L3VPNMPLS L3VPN is a kind of PE-based L3VPN technology for service provider VPN solutions. It uses BGPto advertise VPN routes and uses MPLS to forward VPN packets on service provider backbones.MPLS L3VPN provides flexible networking modes, excellent scalability, and convenient support forMPLS QoS and MPLS TE. Hence, it is widely used.The MPLS L3VPN model consists of three kinds of devices:z Customer edge device (CE): A CE resides on a customer network and has one or more interfacesdirectly connected with service provider networks. It can be a router, a switch, or a host. It neithercan "sense" the existence of any VPN nor needs to support MPLS.
