In this chapter, we took an extremely close look at IP, first discerning precisely why IP, as a network layer protocol, was unique from the transport layer protocols that we've examined before it and then learning about the functions and use of IP through its origin. We looked at when the split was made between the transport layer responsibilities of TCP and the network layer responsibilities of what eventually became IP. In doing so, we established clear boundaries on the scope of IP and what functions it is meant to provide, and what functions fall outside its scope.
Once we established the scope and intent of IP, we looked closely at how it has evolved over the years. Starting with IPv4, we learned about the addressing scheme, how it came to be, and how it is used by network software to uniquely identify hosts on a network. We learned about the common mechanisms...
