This document provides an overview of internet architecture and routing protocols. It discusses the key concepts of routing protocols including how they communicate between source and destination but do not move data, and how they each have their own algorithm to determine the best path. It then covers different types of routing protocols including static, default, distance vector and link state protocols. For each it provides examples (e.g. RIP, OSPF, EIGRP) and discusses their characteristics and advantages/disadvantages. Finally, it dives deeper into the algorithms and processes used for link state routing protocols.