Chapter 2: The OSI Model

Overview

THE FOLLOWING NETWORK+ EXAM OBJECTIVES ARE COVERED IN THIS CHAPTER:

• 1.2 Specify the main features of 802.2 (LLC), 802.3 (Ethernet), 802.5 (Token Ring), 802.11b (wireless), and FDDI networking technologies, including:

  • Speed

  • Access

  • Method

  • Topology

  • Media

• 2.1 Given an example, identify a MAC address.

• 2.2 Identify the seven layers of the OSI model and their functions.

• 2.3 Differentiate between the following network protocols in terms of routing, addressing schemes, interoperability, and naming conventions:

  • TCP/IP

  • IPX/SPX

  • NetBEUI

  • AppleTalk

• 2.4 Identify the OSI layers at which the following network components operate:

  • Hubs

  • Switches

  • Bridges

  • Routers

  • Network interface cards

You can’t open a book on networking technologies without reading about the Open Systems Interconnect (OSI) model. This book is no exception, and for good reason. The OSI model helps us understand the fundamentals of network data transmission by offering a guideline to sending data from one computer to another. In this chapter, we will discuss the makeup of the various network models and, specifically, the most commonly discussed network model, the OSI model.