This document contains 7 questions about Open Shortest Path First (OSPF) routing protocol. It asks about the advantages of multi-area OSPF, the 2-layer area hierarchy in OSPF, Cisco's recommendation for routers per area, the 4 types of OSPF routers, identifying router types in a topology, explaining the first 5 OSPF Link State Advertisements (LSAs), and differentiating inter-area and external route summarization in multi-area OSPF.