Routing protocols are the rules used by routers to discover routes, generate routing tables, and guide packet forwarding. Routes are classified into the following types according to their origin:
Direct routes: are discovered by link layer protocols.
Static routes: are manually configured by network administrators.
Dynamic routes: are discovered by dynamic routing protocols.
Static routes are easy to configure, have low system requirements, and apply to simple, stable, and small networks. The disadvantage of static routes is that they require subsequent maintenance as they cannot automatically adapt to network topology changes.
Dynamic routing protocols have routing algorithms. Therefore dynamic routes can automatically adapt to network topology changes and apply to networks on which Layer 3 devices are deployed. The disadvantages of dynamic routes are that they are complex to configure, have higher system requirements than static ones, and consume network and system resources.