The philosophy behind link state routing is that every router attempts to build its own internal map of the network topology.
Each router periodically sends status messages to the network.
These status messages list the network's other routers to which the router is directly connected and also the status of the link (whether the link is currently operational).
The routers use the status messages received from other routers to build a map of the network topology.
When a router has to forward a datagram, it chooses the best path to the destination based on the existing conditions.