Learning path
Routing Protocols
Learners who already understand basic networking and want a rigorous, protocol-by-protocol understanding of dynamic routing.
Go deep on how routers actually choose paths: routing-table fundamentals, then RFC-grounded, packet-by-packet internals of RIP, OSPF, EIGRP, and BGP.
Modules and lessons
Introduction to Routing
The concepts every routing protocol builds on: administrative distance, metrics, and the distance-vector, link-state, and path-vector families.
Routing Fundamentals: Administrative Distance and Metrics
Explain how a router chooses between competing routes using administrative distance and protocol metrics, and identify which algorithm family (distance-vector, link-state, or path-vector) each routing protocol belongs to.
RIP
The oldest distance-vector protocol still in use, and why its simplicity is both its strength and its limit.
RIP: Routing Information Protocol
Explain how RIP exchanges routes by hop count, prevents loops with split horizon and triggered updates, and where its RFC 2453 packet format and limits show up in practice.
OSPF
The dominant link-state interior gateway protocol: areas, LSAs, and Dijkstra's algorithm in practice.
OSPF: Open Shortest Path First
Explain how OSPF routers form adjacencies, flood link-state advertisements, and compute shortest paths per RFC 2328.
EIGRP
Cisco's advanced distance-vector protocol and the DUAL algorithm that makes it fast and loop-free.
EIGRP: Enhanced Interior Gateway Routing Protocol
Explain how EIGRP's DUAL algorithm finds loop-free successors and feasible successors, and how its composite metric is calculated per RFC 7868.
BGP
The path-vector protocol that holds the Internet together, and the policy-driven decisions behind it.
BGP: Border Gateway Protocol
Explain how BGP establishes peering sessions, advertises path attributes, and applies the RFC 4271 decision process to choose a best path.