What structure is used in an OSPF network to create the neighbor table on a router?

In OSPF (Open Shortest Path First) networks, the adjacency database is crucial for maintaining information about neighbor routers. This database is built through the exchange of hello packets, which allow OSPF routers to discover other OSPF-enabled routers on the same link and establish adjacencies.

When routers become aware of their OSPF neighbors, they form these adjacencies, and the adjacency database is populated with the information about each neighbor router, including their interface addresses and other relevant parameters. The neighbor table is derived from this adjacency database, providing a clear view of which adjacent routers are actively participating in OSPF routing on that segment.

Other structures, such as link-state advertisements, play a role in advertising network topology and state information but do not directly serve to create the neighbor table. The routing table contains the best paths calculated by OSPF and other routing protocols but does not focus specifically on OSPF neighbors. The topological database, while it holds the complete view of the OSPF area, is separate from the immediate neighbor information that the adjacency database contains. Thus, the adjacency database is the correct structure used in an OSPF network to create the neighbor table on a router.