Which of the following categories of routing protocols builds a topology database of the network?

A.
Dynamic

B.
Distance-vector

C.
Link-state

D.
Static

Explanation:
C: Routing protocols indicate how routers talk to each other. Routing protocols circulate information that enables routers to choose a route between two nodes on a network.
Routers then choose a route with the use of a routing algorithm. Each router has knowledge of the networks it is directly attached to. This information is shared with immediate
neighbors, then throughout the network, via a routing protocol. Thus, routers learn about the topology of the network. Two main types of routing protocols are used: distancevector
and link-state routing. Link-state routing protocols build a more accurate routing table than distance-vector protocols because they build a topology database of the
network. Link-state routing protocols look at more variables than just the number of hops between two destinations. They use packet size, link speed, delay, loading, and
reliability as the variables in their algorithms to determine the best routes for packets to take.
A is incorrect because a dynamic routing protocol does not build a topology database of the network. However, a link-state routing table (which does build a topology
database of the network) is classified as a dynamic routing protocol because it discovers routes and builds a routing table. Routers use these tables to make decisions on the
best route for the packets they receive. A dynamic routing protocol can change the entries in the routing table based on changes that take place to the different routes. When a
router that is using a dynamic routing protocol finds out that a route has gone down or is congested, it sends an update message to the other routers around it. The other routers
use this information to update their routing table, with the goal of providing efficient routing functionality.
B is incorrect because distance-vector routing protocols do not build a topology database of the network. Routing protocols are classified as either distance-vector or linkstate.
Distance-vector routing protocols make their routing decisions based on the distance (or number of hops) and a vector (a direction). The protocol takes these variables and
uses them with an algorithm to determine the best route for a packet. Distance-vector routing protocols build a less accurate routing table than link-state because distance-vector
routing protocols use fewer variables to determine the best route.
D is incorrect because a static routing protocol does not build a topology database of the network. Routing protocols can be either dynamic or static. Whereas a dynamic
routing protocol can discover routes and build a routing table on its own, a static routing table requires the administrator to manually configure the router’s routing table.