Protocols, Layers, and Abstraction

How networking is structured
Published

January 8, 2026

Lesson Objectives

  • Explain the role of each layer in the TCP/IP model
  • Define network protocol
  • Explain how protocol design principles enable networks
  • Why abstraction fails under attack or congestion
  • Identify network traffic using Wireshark / Wireview

Preparation

  • \(1.1\) What is the Internet?
  • \(1.5\) Protocol Layers and Their Service Models
  • \(1.6\) Networks Under Attack
  • \(1.2\) The Network Edge (skim)
  • \(1.3\) The Network Core (skim)
  • \(1.7\) History of Computer Networking and the Internet (skim)

Exercise

  • Use Wireview to identify layers and protocols in captured traffic.
  • Map observed protocols to TCP/IP layers.
  • Draw the path of a Signal or Whatsapp message — what must go right?