Welcome to the module TCP and UDP Theory of Operation. From the title,
you might have guessed that we'll be covering the operational theory of
TCP and UDP, and you are correct. In this module,
we're going to cover a bunch of great material that'll
help you garner a better understanding needed to deal
with TCP and UDP‑related issues.
We'll,
first cover a TCP datagram decomposition. A datagram is
the actual composition of a TCP session.
Consider this the DNA of TCP with no dinosaurs coming after us. With the
decomposition completed, we'll then move on to learning how a session is
formed. With a solid understanding of how sessions are formed, we'll then
move on to segmentation and reassembly of data.
With our data correctly reassembled, we'll then move on to error
recovery to learn how missing data is retransmitted. During this
module, we'll use Wireshark quite frequently to help cement this
operational theory that's presented as well. With TCP thoroughly
covered, we'll then move on to UDP.
During our discovery of UDP, we'll first complete a decomposition of the UDP
datagram protocol. With the datagram successfully covered,
we'll then pivot to Wireshark and view an actual datagram captured in
Wireshark. We'll then complete this module by learning how UDP transmits
its data to the receiving machine through the use of the captured network traffic viewed through Wireshark.