Learning Objectives

By the end of this chapter, you will be able to:

  • Define a network protocol and its purpose.
  • Describe the roles of TCP/IP and Ethernet.
  • Identify the key hardware components of a network, including switches, routers, and modems.

Network Protocols: The Rules of Communication

A protocol is a set of rules that governs how data is formatted, transmitted, and received in a network. Just like humans need to speak the same language to communicate, computers need to use the same protocols.

  • TCP/IP (Transmission Control Protocol/Internet Protocol): This is the foundational protocol suite of the internet.
    • IP is responsible for addressing and routing packets of data to the correct destination.
    • TCP is responsible for ensuring that the data is delivered reliably and in the correct order.
  • Ethernet: The most common protocol used for Local Area Networks (LANs).

Networking Hardware

Several key pieces of hardware are required to create a computer network.

  • Switch: A device used to connect multiple computers together on a LAN. A switch receives data from one device and intelligently forwards it only to the specific device it is intended for.

  • Router: A device that connects different networks together. Your home router connects your private LAN to the public internet (a WAN). Routers are responsible for directing traffic between networks.

  • Modem (Modulator-Demodulator): A device that connects your home network to your Internet Service Provider (ISP) over a medium like cable or DSL. It converts the digital signals from your computer into analog signals for transmission over the ISP’s network, and vice versa.

Summary

For computers to communicate, they must follow a common set of rules called protocols, with TCP/IP being the fundamental protocol of the internet. This communication is made possible by key pieces of networking hardware. Switches connect devices on a local LAN, while routers connect different networks together. A modem is the device that provides the connection from your home or business to your Internet Service Provider.

Key Takeaways

  • Protocols are the rules that govern network communication.
  • TCP/IP is the core protocol of the internet.
  • A switch connects devices on a LAN; a router connects different networks.
  • A modem connects your network to your ISP.

Discussion Questions

  1. What is the difference between a switch and a router?
  2. Using an analogy, explain the roles of TCP and IP.
  3. When you connect to the Wi-Fi at a coffee shop, what networking hardware are you interacting with?