As the network administrator, you need to develop a verification plan for an OSPF network. The OSPF network has several area routers, area border routers (ABRs), and autonomous system boundary routers (ASBRs).
Which LSA types should you expect ABRs to generate while verifying the OSPF network? (Choose two.)
- Type 4
- Type 3
- Type 2
- Type 5
ABRs generate Type 3 and Type 4 LSAs in an OSPF network. ABRs are those routers that exist between two OSPF areas, as shown in the following figure:
Type 3 and Type 4 LSAs are generated by ABRs to be flooded into other areas to and from the backbone area (area 0). Type 3 LSAs, or summary link advertisements, contain the list of networks known by one area. ABRs send Type 3 LSAs to the other OSPF areas in a given AS.
OSPF ABRs generates Type 4 LSAs to advertise the list of routes that point to an ASBR. These LSAs advertise the location of the ASBR.
Type 5 LSAs are not generated by an ABR. These LSAs are generated by ASBRs to describe routes redistributed into the area from other autonomous systems.
Type 2 LSAs are not generated by an ABR. A Type 2 LSA is generated only by the designated router (DR) of a segment to be sent to the other routers that belong to the same area as the DR. A DR is a router that has the highest OSPF priority on a segment. These advertisements are used by the DR to represent the routers that are connected to the network.
Layer 3 Technologies
Configure and verify network types, area types, and router types