By now, you should have a solid understanding of the role and purpose of the IP, and its influence in addressing and routing data. In this chapter, we covered a brief history of IP. We now know that both versions of IP can do the job of routing and addressing; however, there are several differences between the IPv4 and IPv6 headers. We then examined and explained each of the field values of both IPv4 and IPv6. To give you a better understanding of the two protocols, we compared some of the similarities along with some of the differences between IPv4 and IPv6. 

To help strengthen your knowledge of addressing, we briefly covered the classes of IPv4 addresses, along with reviewing the different types of IPv6 addresses. We then looked at how you can personalize the settings for IPv4 and IPv6 by modifying the protocol preferences. Finally, because of the need for both IP versions to coexist on today's networks, we compared the different types of tunneling protocols in use today.

In the next chapter, we will learn about ICMP, the sister protocol to IP that works in the network layer of the OSI model. We will evaluate both ICMP, which is used for IPv4, and ICMPv6, which is used with IPv6. We'll take a deep dive into how ICMP works in both versions, and you will have a better understanding of the two types of messages: error reporting and queries. At the end of the chapter, you'll see how ICMP is the scout for IP and how its use is essential in delivering data.