CCNA EXPLORATION ONE
Data networks and the Internet support the human network by supplying seamless, reliable communication
between people - both locally and around the globe. On a single device, people can use multiple service
6.0.1 Chapter Introduction
Addressing is a key function of Network layer protocols that enables data communication between hosts on
the same network or on different networks. Internet Protocol version 4 (IPv4) provides hierarchical
To support our communication, the OSI model divides the functions of a data network into layers.
The Application layer provides the interface to the user.
The Transport layer is responsible for dividing and managing commu
CCNA Exploration 1
More and more, it is networks that connect us. People communicate online from everywhere. Efficient,
dependable technology enables networks to be available whenever and wherever we need them. As our
CCNA Exploration 1
Most of us experience the Internet through the World Wide Web, e-mail services, and file-sharing programs.
These applications, and many others, provide the human interface to the underlying network, enabling
Before using an IP phone, accessing instant messaging, or conducting any number of other interactions
over a data network, we must connect end devices and intermediary devices via cable or wireless
5.0.1 Chapter Introduction
We have seen how network applications and services on one end device can communicate with applications
and services running on another end device.
Next, as shown in the figure, we will consider how this d
Upper OSI layer protocols prepare data from the human network for transmission to its destination. The
Physical layer controls how data is placed on the communication media.
The role of the OSI Physical layer is
9.0.1 Chapter Introduction
Up to this point in the course, each chapter focused on the different functions of each layer of the OSI and
TCP/IP protocol models as well as how protocols are used to support network communication. Seve
In this chapter, we will examine the process for connecting and configuring computers, switches,
and routers into an Ethernet LAN.
We will introduce the basic configuration procedures for Cisco network devices.