As networks grow in size and complexity, distance vector routing protocols become inefficient. This episode introduces link-state and hybrid routing protocols—more sophisticated tools for modern routing. We begin with OSPF, a link-state protocol that uses a cost metric and maintains a full map of the network. You'll learn how areas and LSAs (Link-State Advertisements) work, how OSPF selects the shortest path using Dijkstra’s algorithm, and how it quickly converges after changes.

We then explore EIGRP, Cisco’s hybrid protocol that combines features of both distance vector and link-state models, offering fast convergence and granular control. Finally, we introduce BGP, the backbone of internet routing, and explain how it uses path vector logic to manage routes between autonomous systems. Understanding these protocols is critical for the exam and essential for working in any medium-to-large network environment.