The basic BGP/MPLS IP VPN refers to a VPN that is established on one SP's MPLS backbone network that does not span multiple ASs. The role of each PE, P, or CE of the basic BGP/MPLS IP VPN is unique. For example, a router cannot function as both a PE and a CE.
The system selects LSP tunnels for VPN data transmission and implements no load balancing by default. To implement tunnel load balancing or select other types of tunnels, configure a tunnel policy to select tunnels based on priorities and then apply the tunnel policy.
In the Hub and Spoke networking, an access control device is specified in the VPN, and users communicate with each other through the access control device.
In inter-AS VPN Option B through MP-EBGP, two ASBRs receive VPNv4 routes from PEs in their respective ASs and exchange the VPNv4 routes with each other.
After LDP LSPs are established for the labeled BGP routes of the public network, EBGP connections in multi-hop mode are established between PEs of different ASs to exchange VPNv4 routes.
This section describes how to configure the routes that traverse the MPLS VPN backbone network to be the routes of the OSPF area. After the configuration, traffic between sites of the same VPN in the same OSPF area need not be forwarded through routes of the OSPF area.
Generally, users within a VPN can communicate only with each other, but cannot communicate with Internet users because VPN users cannot access the Internet. If each VPN site needs to access the Internet, configure the interconnection between the VPN and the Internet.