Читать книгу CCENT ICND1 Study Guide - Lammle Todd - Страница 14

THE FOLLOWING ICND1 EXAM TOPICS ARE COVERED IN THIS CHAPTER:

✓ Network Fundamentals

■ 1.3 Describe the impact of infrastructure components in an enterprise network

■ 1.3.a Firewalls

■ 1.3.b Access points

■ 1.3.c Wireless controllers

■ 1.5 Compare and contrast network topologies

■ 1.5.a Star

■ 1.5.b Mesh

■ 1.5.c Hybrid

Welcome to the exciting world of internetworking. This first chapter will serve as an internetworking review by focusing on how to connect networks together using Cisco routers and switches, and I’ve written it with the assumption that you have some simple basic networking knowledge. The emphasis of this review will be on the Cisco CCENT and/or CCNA Routing and Switching (CCNA R/S) objectives, on which you’ll need a solid grasp in order to succeed in getting your certifications.

Let’s start by defining exactly what an internetwork is: You create an internetwork when you connect two or more networks via a router and configure a logical network addressing scheme with a protocol such as IP or IPv6.

We’ll also dissect the Open Systems Interconnection (OSI) model, and I’ll describe each part of it to you in detail because you really need complete, reliable knowledge of it. Understanding the OSI model is key for the solid foundation you’ll need to build upon with the more advanced Cisco networking knowledge gained as you become increasingly more skilled.

The OSI model has seven hierarchical layers that were developed to enable different networks to communicate reliably between disparate systems. Since this book is centering upon all things CCNA, it’s crucial for you to understand the OSI model as Cisco sees it, so that’s how I’ll be presenting the seven layers to you.

After you finish reading this chapter, you’ll encounter review questions and written labs. These are given to you to really lock the information from this chapter into your memory. So don’t skip them!

To find up-to-the-minute updates for this chapter, please see www.lammle.com/ccna or the book’s web page via www.sybex.com/go/ccna.