Network Layer Part II – Routing
Oliver C. Ibe · 2017
This chapter discusses the network layer service of IP addressing. It includes the following: routing principle, routing algorithms, unicast routing protocols and multicast routing. The chapter deals with multicast routing with discussion on the different types of multicast protocols: opt-in versus opt-out. Routing is the process of forwarding messages from source to destination through a packet-switched network. Routing algorithms can be classified in several ways, some of which include the following: static routing versus dynamic routing, link-state routing versus distance-vector routing, flat routing versus hierarchical routing, host-intelligent routing versus router-intelligent routing and centralized versus distributed routing algorithms. Routing algorithms use many different metrics to determine the best route. The chapter also discusses Dijkstra's algorithm, is guaranteed to find a shortest path from the starting point to the target destination node provided none of the edges has a negative cost. It provides two types of multicast trees which are source-based trees and shared trees.