Which OSPF LSA type describes the links attached to a router (its neighbors and interface connections)?

Which OSPF LSA type describes the links attached to a router (its neighbors and interface connections)?

• A. Network-LSA
• B. Router-LSA
• C. Summary-LSA
• D. AS-External-LSA

Answer: (B)

OSPF uses LSAs to describe how a router is connected to the network. The Router-LSA (Type 1) is generated by every router and lists the links that belong to that router—its interfaces, the type of each link (point-to-point to another router or a transit/stub network), the neighboring routers on those links, and the cost to reach those destinations. This is exactly describing the links attached to a router and its immediate neighbor relationships. The Network-LSA (Type 2) describes the network segment itself on multi-access networks and lists which routers are on that network, which is a different perspective. Summary-LSA (Type 3) carries inter-area route summaries, and AS-External-LSA (Type 5) carries routes external to the OSPF AS.

OSPF uses LSAs to describe how a router is connected to the network. The Router-LSA (Type 1) is generated by every router and lists the links that belong to that router—its interfaces, the type of each link (point-to-point to another router or a transit/stub network), the neighboring routers on those links, and the cost to reach those destinations. This is exactly describing the links attached to a router and its immediate neighbor relationships.

The Network-LSA (Type 2) describes the network segment itself on multi-access networks and lists which routers are on that network, which is a different perspective. Summary-LSA (Type 3) carries inter-area route summaries, and AS-External-LSA (Type 5) carries routes external to the OSPF AS.