In this chapter, we saw that:
Layered models for networking communication allow interoperability, ease of use, and a faster growth of the Internet.
The TCP/IP model is the most popular model, but the OSI model is used as a reference in network communication. For example, TCP, which is at TCP/IP Layer 3, is referred to as a Layer 4 protocol.
TCP is a connection-oriented and reliable protocol that implements flow-control, while UDP is much simpler, and provides connectionless, unreliable delivery of packets.
IP classes A, B, C, D, and E were defined.
Subnetting is a process to divide an IP class into smaller pieces by borrowing bits from the host part of the IP address to the network part.
CIDR or IP supernetting is an IP addressing scheme that allows a more efficient management of IP addresses and aggregation for reducing the size of routing tables.
Providers exchange routing information using the Border Gateway Protocol, thus making the Internet work.