The focus of this chapter has largely been on the mechanisms by which a device's internet layer (or OSI network layer) identifies itself and how it maps to the network interface (or OSI data link) layer. Internet layer protocols such as ARP and ICMP, that are important to routing, were also examined. The following chapter examines a newer version of IP, IP version 6, how it differs from IPv4, and why a new version of IP is needed. |