What are two benefits of using a single OSPF area network design? (Choose two.)
A.
It is less CPU intensive for routers in the single area.
B.
It reduces the types of LSAs that are generated.
C.
It removes the need for virtual links.
D.
It increases LSA response times.
E.
It reduces the number of required OSPF neighbor adjacencies.
Virtual links can be considered as duct tape for OSPF: They can fix things in a pinch, but aren’t intended to be a permanent solution and should never comprise your original design.
The link-state advertisement (LSA) is a basic communication means of the OSPF routing protocol for the Internet Protocol (IP). It communicates the router’s local routing topology to all other local routers in the same OSPF area. OSPF is designed for scalability, so some LSAs are not flooded out on all interfaces, but only on those that belong to the appropriate area. In this way detailed information can be kept localized, while summary information is flooded to the rest of the network. The original IPv4-only OSPFv2 and the newer IPv6-compatible OSPFv3 have broadly similar LSA types.