Introduction to Networks

Appendix B. Network Fundamentals

This appendix describes the fundamental concepts that relate to networks and includes the following sections:

• Introduction to Networks

• Protocols and the OSI Model

• LANs and WANs

• Network Devices

• Introduction to the TCP/IP Suite

• Routing

• Addressing

• Comprehensive Example

The goal of this appendix is to introduce some fundamental concepts and terminology that are the foundation for the other material in the book. After a brief introduction to networks in general, we delve into the communication protocols that are used by network devices; this necessarily includes a discussion of the infamous Open Systems Interconnection (OSI) model. LANs and WANs are described, as are the various devices found in a network. This is followed by an introduction to the Transmission Control Protocol/Internet Protocol (TCP/IP), used extensively in the Internet. Routing and addressing, including IP addresses, are explored. The appendix concludes with a comprehensive example, tying together many of the concepts covered.

We encourage you to review any of the material in this appendix that you are not familiar with before reading the rest of the book, because these ideas are critical to the understanding of the more complex technologies covered in the other chapters.