37276899-29-wifi
TRANSCRIPT
-
8/8/2019 37276899-29-WiFi
1/33
INTRODUCTION
An expensive broadband network that can
keep you connected while you move about
home or office. the broadband wireless web is being built
around the technology called WI-FI.
WI-FI is stand for WIRELESS FIDELITY.
-
8/8/2019 37276899-29-WiFi
2/33
WHAT IS WI-FI?
WI-FI is a trade-group certified wirelessnetworking standard that relies on the IEEE802.11a and 802.11b specification.
802.11b specification allows for thewireless transmission of approximately 11mbps of raw data at indoor distances from
several dozen to several hundred feet andoutdoor distances of several to tens of milesas an unlicensed use of 2.4 ghz band.
-
8/8/2019 37276899-29-WiFi
3/33
The 802.11a specification uses 5Ghz band
and can handle 54 mbps at typically shorter
distances.The distances for both standards depends on
impediments,materials and line of sight.
WI-FI is an extension of ethernet,bringing
the same principles to wireless
communication.
-
8/8/2019 37276899-29-WiFi
4/33
WHY WI-FI?
1) MOBILITY
2) SCALABILITY
3) INCRESED RELIABILITY 4) REDUCED INSTALLATION TIME
5) FINANCIAL BENEFIT
6) LONG TERM COST SAVINGS
-
8/8/2019 37276899-29-WiFi
5/33
WI-FI STANDARDS
1) 802.11:
This standard allows wireless connection
up to 300 feet from an access point and can easilybe added to existing wired networks with speeds
up to 11 mbps.
2) 802.11a:
This provides a bigger pipe for data and
supports more simultaneous users.
it can support up to 54 mbps.
-
8/8/2019 37276899-29-WiFi
6/33
3) 802.11b:
The popular 802.11b WI-FI
devices broadcast in the 2.4Ghz band usedby cordless phones.
-
8/8/2019 37276899-29-WiFi
7/33
COMPONENTS OF WI-FI
There are currently two types ofcomponents.
1) WI-FI radio devices
2) Access points or gateway that act asbasestation.
A third type WI-FI equipped
peripherals are emerging and will soon becommonplace.this group includesprinters,scanner ,cameras etc.
-
8/8/2019 37276899-29-WiFi
8/33
Some components of WI-FI
j PC CARD RADIO.
-
8/8/2019 37276899-29-WiFi
9/33
j MINI-PCI
MODULES AND
EMBEDDED
RADIOS.
-
8/8/2019 37276899-29-WiFi
10/33
j USB ADAPTERS
-
8/8/2019 37276899-29-WiFi
11/33
j PCI AND ISA BUS
ADAPTERS.
-
8/8/2019 37276899-29-WiFi
12/33
j ACCESS POINTS
AND GATEWAY.
-
8/8/2019 37276899-29-WiFi
13/33
WHAT TRANSMISSION
TECH.WI-FI USED?1) NARROWBAND TECHNOLOGY
2) SPREAD SPECTRUM TECHNOLOGY
3) FREQUENCY HOPPING SPREADSPECTRUM (FHSS).
4) DIRECT SEQUNCE SPREAD
SPECTRUM (DSSS).
-
8/8/2019 37276899-29-WiFi
14/33
ABOUT NETWORK
WHAT MAKES UP A WIRELESS NETWORK
?
Wi-Fi devices "connect" to each other by
transmitting and receiving signals on a specific
frequency of the radio band. Your components can
connect to each other directly or through a
gateway oraccess point. When you create your
Wi-Fi network it will consist of two basic
components: Wi-Fi radios and access points orgateways.
-
8/8/2019 37276899-29-WiFi
15/33
PLANNING FOR ACCESS POINTS AND
GATEWAY..
A Wi-Fi network operates more effectivelywhen using a central wireless base station to
coordinate communications. There are two
types: a gateway and an access point.
Most home and small office networks should
use a Wi-Fi gateway.
-
8/8/2019 37276899-29-WiFi
16/33
HOW MANY USERS CAN USE
A SINGAL ACCESS POINT?j Wi-Fi neWtworks, like wired networks, are a
shared medium. An 802.11b Wi-Fi network mayprovide 11 Mbps of bandwidth to an individual
user. Theoretically, if ten users are simultaneouslyusing the network, each will have to share andmay only get 1 Mbps or so each. However,network sharing is not quite this simple. A lotdepends on the users' behaviors. Someone who is
just sending and receiving e-mail just uses thewireless connection in bursts. They will probablynever notice any slow down.
-
8/8/2019 37276899-29-WiFi
17/33
j On the other hand, a roomful of Wi-Fi users who
are accessing high-resolution multimedia over a
single access point may indeed notice a slowdown.
j A singal access point can easily handle 10 to 30
users who use the n/w for sending or receving e-
mail.
j Within typical office environment most access
point can provides good wireless coverage up to
150 feet or so.
-
8/8/2019 37276899-29-WiFi
18/33
HOW TO INSTALL YOUR
ACCESS POINT OR GATEWAYj During the installation, make sure you follow the
manufacturer's instructions to install an access
point- or gateway-based network, not a peer-to-
peer network. For most Wi-Fi systems, you mustfirst plug in and power up the base station. Then
connect the Ethernet cable from your DSL or
cable modem to the base station. If your
broadband connection is already connected to yourcomputer, disconnect that cable and attach it to
your base station.
-
8/8/2019 37276899-29-WiFi
19/33
j Most cable and DSL modems use Ethernettechnology (cable and built in card) to connect tocomputers or to networks. However, some
versions of DSL or cable modemsuse a
USBcable to connect to computers. Find out whichyour system uses because few if any Wi-Fi accesspoints can use USB for their broadbandconnection. If your broadband modem connects
using a USB cable, you then need to buy thecorrect RJ-45 Ethernet cable to connect yourmodem to your Wi-Fi gateway or access point.
-
8/8/2019 37276899-29-WiFi
20/33
INSTALL THE FIRST WI-FI
RADIO DEVICE..j After carefully reviewing instructions, install the
Wi-Fi radio device in the first computer. If you're
installing devices in both desktops and laptops,
start with the machine with the newest operatingsystem. Follow the manufacturer's instructions to
be sure you're configuring them to work with your
base station and not as a peer-to-peer network. If
all your OS's, or operating systems, are about thesame, begin by installing PC Card radios in the
laptops and then install in the desktops
-
8/8/2019 37276899-29-WiFi
21/33
HOE DO U CONNECT YOUR WI-FI
N/W TO THE INTERNET ?
j WI-Fi You can use a variety of high-speed
Internet connections with a Wi-Fi network,
including cable modems, different types of DSL,
satellite broadband, etc. Your broadband Internetconnection will connect to your gateway or access
point, and its Internet connection will be
distributed to all the computers on your network.
And don't worry about Wi-Fi slowing down yourconnection speed: it's at least four times faster than
the fastest of any of these connection.
-
8/8/2019 37276899-29-WiFi
22/33
TOPOLOGY DESIGN AP..
jWE HAVE TO DESIGN AP BY WHICH
WE CAN GET MINIMUM OVERLAP
AND MAXIMUM FIDELITY.
j Here Klskf will discuss on ideal AP
coverage,the coverage volume of the AP is
shown in fig as three coaxial cylinders.
-
8/8/2019 37276899-29-WiFi
23/33
j Middle cylinder
reprensting coverage on
floor on which the axis
point is located with
radius R.
j The upper and lower
cylinder reprensting the
coverage on the floors
above and below the oneon which the AP is locate
with radius R less than R.
-
8/8/2019 37276899-29-WiFi
24/33
DESIGN PROCEDURE..
jFOLLOWING ARE THE FOUR
SCENARIO WHICH Klskf USED TO
DESIGN.
j Solid lines show coverage on a floor.
j Dashed line show adjacent floor coverage.
-
8/8/2019 37276899-29-WiFi
25/33
j Scenario 1 : single-floor linear array,
illustrated in fig A
single story buildingwhose width is not
large relative to R,D
denotes the
distance betweenadjacent Access
points
-
8/8/2019 37276899-29-WiFi
26/33
j Scenario 2 :
j single floor rectangulararray illustrated in fig A
single story buildingwhose width(smallestouter dimension)is largerelative to R D denotesthe distance between
two AP's .
-
8/8/2019 37276899-29-WiFi
27/33
j Scenario 3
j : multi floor linear
array illustrated in figA multistory buildingwhose width is notlarge relative to R and
R' ,D' denotes thedistance betweenadjacent APs ondifferent floors.
-
8/8/2019 37276899-29-WiFi
28/33
j Scenario 4: Multi floor
rectangular array ,
illustrated in fig A
multistory building whose
width is large relative to
R and R',D denotesthe
distance between adjacent
APs on the same floor ,
and D' denotes thedistance between adjacent
APs on different floors
-
8/8/2019 37276899-29-WiFi
29/33
WI-FI VS BLUETOOTH..
-
8/8/2019 37276899-29-WiFi
30/33
WI-FI SECURITY
jWI-FI CERTIFIED = CONFIDENCE
jWI-FI PROTECTED ACCESS
jENHANCED DATA ENCRYPTIONTHROUGH TKIP(TEMPORAL KEY
INTEGRITY PROTOCOL).
j
WI-FI PROTECTED ACCESS FORHOME/SOHO.
-
8/8/2019 37276899-29-WiFi
31/33
WI-FI APPLICATION..
j 1) WIRELESS EDUCATION
j 2) WIRELESS BUSINESS CENTERS
j 3) SMALL OFFICESj 4)HOSPITALS
j 5) ACCOUNTING
j 6) WAREHOUSE
-
8/8/2019 37276899-29-WiFi
32/33
WI-FI PRODUCTS..
-
8/8/2019 37276899-29-WiFi
33/33
CONCLUSION..
jFor now ,WI-FI primarily provides
broadband internet access to specially
outfitted pcs and laptops .but in future may
be most of hotspots be wireless.
jBy WI-FI our time and money both are
save..