173
Figure 51
Scenario where the Level 2 carrier is an MPLS L3VPN service provider
NOTE:
If equal cost routes exist between the Level 1 carrier and the Level 2 carrier, HP recommends that you
establish equal cost LSPs between them.
Nested VPN
The nested VPN technology exchanges VPNv4 routes between PEs and CEs of the ISP MPLS L3VPN and
allows a customer to manage its own internal VPNs.
shows a nested VPN network. On the
service provider's MPLS VPN network, there is a customer VPN named VPN A. The customer VPN
contains two sub-VPNs, VPN A-1 and VPN A-2.
The service provider PEs consider the customer's network as a common VPN user and do not join any
sub-VPNs. The service provider CE devices (CE 1 and CE 2) exchange VPNv4 routes including sub-VPN
routing information with the service provider PEs, which implements the propagation of the sub-VPN
routing information throughout the customer network.
The nested VPN technology supports both symmetric networking and asymmetric networking. Sites of the
same VPN can have the same number or different numbers of internal VPNs. Nested VPN also supports
multiple-level nesting of internal VPNs.