CCNA Cisco Certified Network Associate Study Guide - FTP Server

Welcome to the exciting world of internetworking. This
first chapter will help you understand the basics of internetworking and how
to connect networks using Cisco routers and switches.
The Open Systems Interconnection (OSI) model will be discussed in detail
in this chapter. The OSI model has seven hierarchical layers that were developed
to help different companies communicate between their disparate systems.
It is important to understand the OSI model as Cisco sees it, and that
is how I will present the seven layers of the OSI model to you.
Cisco has created a three-layer hierarchical network model that can help
you build, implement, and maintain networks. By understanding this model,
you can effectively build, maintain, and troubleshoot any size network. This
chapter will give you both an introduction to the Cisco three-layer model
and the details of each layer.
Different types of devices are specified at different layers of the OSI
model. It is important to understand the different types of cables and connectors
used to connect these devices to a network. Cabling Cisco devices
will be discussed with Ethernet LANs, WAN technologies, and even connecting
a router or switch with a console connection.
Cisco makes a large range of router, hub, and switch products. By understanding
the different products available from Cisco, you can understand
which devices can meet the business requirements for your network. The
product line for Cisco hubs, routers, and switches is discussed at the end of
this chapter.