CHAPTER 9 Forwarding IP Packets
What You Will Learn
In this chapter, you will learn how routers forward IP packets. We’ll start with the logical steps a router follows to forward (“route”) a packet out the next-hop interface. Then we’ll look at router architectures to see how specialized devices (there are “software-only” routers) accomplish routing and forwarding.
Finally, you will learn about how IPv4 routers transition to handling IPv6 routing and various methods to tunnel IPv6 packets through links connected by IPv4-only routers. Tunnels were introduced in Chapters 3 and 4 and occur when the normal encapsulation sequence of packet–inside frame is violated in some fashion.
This chapter is really a continued investigation into many of the ...