Exhibit:
What is the interaction between a super-backbone and Area 3?
A.
The super-backbone appears as a NSSA to the non-backbone OSPF routers of Area 3.
B.
The super-backbone appears as BGP domain to the non-backbone OSPF routers of Area 3.
C.
The super-backbone appears as another OSPF area to the non-backbone OSPF routers of
Area 3.
D.
The super-backbone appears as Area 0 (backbone area) to the non-backbone OSPF routers of
Area 3.
Explanation:
Traditionally, an elaborate OSPF network consists of a backbone area (area 0) and a number of
areas
connected to this backbone via an area border router (ABR). By using an MPLS backbone for
VPN with OSPF
on the customer’s site, you can introduce a third level in the hierarchy of the OSPF model. This
third level is called the MPLS VPN super backbone.
In simple cases, the MPLS VPN super backbone is combined with the traditional area 0 backbone.
This means that there is no area 0 backbone on the customer network, since the MPLS VPN
super backbone plays the same role as the area 0 backbone. This is shown in the diagram below:http://www.cisco.com/warp/public/121/mpls_ospf2.html