Modern networks function reliably because both devices and software follow established rules. These rules are defined by standards and protocols. A protocol is a formal agreements that specify how particular aspects of a network should operate. Due to the vast number of such protocols and standards, understanding and managing networks can become complex. To bring structure to this complexity, the networking field relies on conceptual frameworks known as networking models.

"Do you know this already?" checkpoint

The “Do you know this already?” section helps you check how well you understand the topics before starting the lessons. The following interactive quiz is designed to test if you can safely skip the following section. Additionally, it will put you up to speed with the topic we cover in the section's underlying lessons. Keep in mind that you can make the page wider using the hidden page control on the left-center side of the page.