What information does a router running a link-state protocol use to build and maintain its
topological database? (Choose two.)
A.
hello packets
B.
SAP messages sent by other routers
C.
LSAs from other routers
D.
beacons received on point-to-point links
E.
routing tables received from other link-state routers
F.
TTL packets from designated routers
Each router is responsible for meeting its neighbors on directly connected networks. Link-state routers do this by exchanging Hello packets with other link-state routers on directly connected networks.
Each router builds a link-state packet (LSP)containing the state of each directly connected link. This is done by recording all the pertinent information about each neighbor, including neighbor ID, link type, and bandwidth.
Each router floods the LSP to all neighbors. Those neighbors store all LSPs received in a database. They then flood the LSPs to their neighbors until all routers in the area have received the LSPs. Each router stores a copy of each LSP received from its neighbors in a local database.
Each router learns about its own links and its own directly connected networks. This is done by detecting that an interface is in the up state.
Each router stores a copy of each LSP received from its neighbors in a local database.
Each router uses the database to construct a complete map of the topology and computes the best path to each destination network.