Transcript Communications and Networks

Networks
Intro to Digital Technology
Follow along and fill in your Guided Notes Handout.
What is a Computer Network?
 A collection
of computers
and devices
connected
together
Why would a Business use a Network?
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Facilitate communications
Share hardware
Share data & information
Share software
Transfer funds
Advantages of Networking
 Facilitating Communications-email, IM, chat rooms,
blogs, etc.
 Sharing hardware-save money
 Sharing data & information-access to database for
customers
 Sharing software-save money
 Transferring funds-payroll, make purchases on the
Internet
Types of Networks – 4 Types
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Local area network (LAN)
Wireless local area network (WLAN)
Metropolitan area network (MAN)
Wide area network (WAN)
Difference: the area of coverage
LAN
 Limited
geographical area
 Home
 School computer
lab
 Office
building
WLAN
 LAN with no
physical wires
 Usually
communicates
with a wired LAN
MAN
 High- speed network that connects LANs in a
metropolitan area such as a city or town and handles
the bulk of communications activity across that
region.
 Regulated by local or state government
 Provided by telephone companies, cable television
operators, and other organizations
WAN
 Covers a large geographic
area ( such as a city,
country, or the world)
 Combines many types of
media such as telephone
lines, cables, and radio
waves
 What is the world’s largest
WAN?
Network Architectures
 Design of computers, devices, and media in a network
 Two Categories
 Client/server
 Peer-to-peer
Do you know any examples?
Client/Server
 Server-host computer
 Controls access to hardware, software, and other
resources
 Provides central storage area
 Clients
 Other computers and devices on the network that rely
on the server for resources
 EX. Server stores database of customers, Client
access database
Client/Server
 EX. Server stores
database of customers,
Client access database
 10 or more computers
Peer-to-Peer Network
 Simple, inexpensive
 Less than 10
computers
 Equal responsibilities
and capabilities
Internet Peer-to-Peer (P2P
 Users access each others
hard disks and exchange
files directly over the
Internet
 Examples:
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Limewire
BitTorrent
Gnutella
Kazaa
Network Topologies
 Layout of the computers and devices in a
communications network.
 Three most common:
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Bus
Ring
Star
Mesh
Types of Topologies
Bus Network
 Single central
cable, to
which all
computers
and other
devices
connect
Ring Network
 A cable forms a
closed loop (ring)
with all computers
and devices
arranged along the
ring
Star Network
 All of the computers and
devices ( nodes) on the
network connect to a
central device, thus
forming a star
Mesh Network
 Each component
is connected to
every other
component.
Intranet
 Internal network that uses Internet technologies
 Make company information accessible to employees
 Examples:
 telephone directories, event calendars, procedure manuals,
employee benefits information, and job postings
What about an example here in the school?
Learn About Networks
 PBS Interactive Lesson