Protocols were introduced in Chapter 3, "Understanding Network Architecture," and discussed in Chapter 5, "Introducing Network Standards." Protocols are the system of rules and procedures that govern communication between two or more devices. Many varieties of protocols exist. Not all protocols are compatible, but as long as two devices are using the same protocol, they can exchange data. In this chapter, we discuss the prominent protocols used with networks and define the relationship of each protocol to the OSI reference model covered in Chapter 5.
Before starting this chapter, you will find it helpful to review Lesson 1: Open Systems Interconnection (OSI) Reference Model in Chapter 5.