Last week, we actually did Chapters 3 and 4 together, but I only titled it Chapter 3. Chapter 3 was the “IPv4” portion, and chapter 4 was the “IPv6” portion. Today, we go over Chapter 5, for TCP/IP layer 4 Transport.
The Transport layer covers more than just TCP. It includes TCP, UDP, ICMP, as well as some less commonly known protocols such as SCTP (stream control transmission protocol,) ESP (encapsulating security payload,) and AH (IPSec Authentication Header.) Lucas mentions that there are dozens more, but these were the opening examples.
He goes into more depth about ICMP, TCP, and UDP, including roles, protocols, and troubleshooting. After this, we get a bit of information on sockets, and how to configure the common services.
Finally, he covers the TCP connection state and the three way handshake, of SYN, SYN-ACK, and ACK, which is necessary for an ESTABLISHED session. A little about the protocols file for defined numbers, and he wraps up the chapter.
Next week, we’ll look at Chapter 6, which is “viewing the network.”