In this age of inter-connectivity and global communication, we must start to look at communicating between networks rather than just between devices on the same subnet. One key component of this communication is the router. This ubiquitous network device allows for efficient communication between networks, whether these are networks internal to our organization or remote networks on the other side of the world. After switches, this is arguably one of the most important network devices for a network engineer to understand.
This chapter introduces the concept of routing and provides you with an explanation of how routing decisions are made. Various routing protocols are explained and the characteristics of each provided. Also, we will introduce you to the concepts of Network Address Translation (NAT) and Quality of Service (QoS).
The...