CCNA (routing and switching)

module 1 – Chapter 1 : Explore the Network

A summary of this chapter

The chapter aims to give you an insight about

  • how multiple networks are used in everyday life
  • Explain the topologies and devices used in a small- to medium-sized business network
  • the basic characteristics of a network that supports communication in a small- to medium-sized business.
  • trends in networking that will affect the use of networks in small to medium-sized businesses

Sizes of the network

  1.  small home network
  2. Small office home office (SOHO)
  3. Medium to Large networks
  4. World wide networks


Need to understand the relationship between Clients and servers

Server : computers that enable to provide info like

  • Email – mail server
  • Web pages – web server
  • Files – file server
  • etc

You need to know the THREE categories of the network structure

DEVICES -laptop ,desktop

Medium (plural media)- cables, fibre

Services – email hosting, applications

End devices: either the source or destinanation of the message.


The chapter goes on to talka bout toplogies.

A topology provides a visual map of how the network is connected.


Physical : indentify the physical local of intermediary devices and cable installation

Logical:identify devices , ports abd addressing scheme.


Types of networks

LAN:Local area networks

WAN : Wide area networks

MAN: metropolitan Area  networks

WLAN : Wireless Lan

SAN: Storage Area network




Internet , Intranet and Extranet

Internet: collection of interconnected networks

Intranet : a private connection of LANs and WANs  that belong to an org

Extranet: providing access to another organisation e.g  econet gives an Ecocash (payments and receipts access ) to ZESA for them to check for all ecocash transactions done to them via ecocash ..(this is just an example handina kuti ndozvinoitika !!!!!!!)




Network Architecture


these are the rules that move data across the network and the characteristics are

  • fault tolerance :  when one link is affect it shouldnt affect others
  • Scalability  : easy to expand
  • Quality of service : managing congestion and giving priority of data e.g prioritising your file server over facebook and youtube
  • Security :network security  and information security



I have attached a summary from Cisco for  chapter 1


Truly yours


Nyasha Charumbira