What is land survey


New Wireless Technology - Wi-fi:

Wireless  Technology:WiFi phones use Skype or Vonage for their
voice over IP service such as current Belkin
About  Wireless  Connection:and Netgear WiFi phones. Several cellular
carriers have created "Dual-mode phones" to
Wireless network refers to any type ofcompete with WiFi Phones, which can be easily
computer network that is wireless, and isswitched between using a WiFi connection when
commonly associated with a telecommunicationsone is available and a traditional cellular
network whose interconnections between nodesnetwork connection when WiFi is not
is implemented without the use of wires, suchavailable.
as  a  computer  network.
?  Advantage  Sides:
Wireless  Connectivity  Types:
It's  fast.
Wireless LAN: Wireless Local Area Network
(WLAN) is similar to other wireless devicesWi-Fi's latest version is many times faster
and uses radio instead of wires to transmitthan DSL or cable connections, and literally
data back and forth between computers on thehundreds of times faster than those old
same  network.dial-up connections. That's particularly
handy when you're working on the run, on the
• Wi-Fi: Wi-Fi is a commonly usedroad, or from home: If you've ever watched
wireless network in computer systems whichseconds tick by while watching Web pages
enable connection to the internet or otherload, you'll appreciate the potential
machines that have Wi-Fi functionalities.productivity  gain.
Wi-Fi networks broadcast radio waves that can
be picked up by Wi-Fi receivers that areIt's  convenient.
attached to different computers or mobile
phones.As soon as a Wi-Fi-equipped device is within
range of a base station, it's online. With no
• Fixed Wireless Data: Fixed wirelesswires, you can move your laptop computer from
data is a type of wireless data network thatplace to place -- for instance, from your
can be used to connect two or more buildingsoffice to a conference room down the hall,
together in order to extend or share thewithout losing your network connection. When
network bandwidth without physically wiringtraveling, you can set up shop anyplace
the  buildings  together.equipped with a Wi-Fi network: another
company's office, a hotel room, or a
?  Wi-Fi  Technology:convention  center.
The purpose of Wi-Fi is to hide complexity byIt's  everywhere.
enabling wireless access to applications and
data, media and streams. The main aims ofPublic Wi-Fi access sites -- or "hot spots"
Wi-Fi  are:-- are multiplying faster than rabbits on
Viagra. They're in bookstores, airport
•  Enable  access to information easilylounges, fast-food restaurants (including
some McDonald's and Schlotzky's Deli
•  Ensure compatibility and coexistenceoutlets), and coffee shops. In addition,
local merchants from Cincinnati to Athens,
•  Get  rid  of  cabling  and  wiringGa., to Portland, Ore., are footing the bill
for bigger hot spots, accessible throughout a
• Get rid of switches, adapters, plugsbusiness  district  or  neighborhood.
and  connectors.
?  Drawbacks:
?  Uses  of  Wi-Fi:
Range:
A Wi-Fi enabled device such as a PC, game
console, cell phone, MP3 player or PDA canWi-Fi networks have limited range. A typical
connect to the Internet when within range ofWi-Fi home router using 802.11b or 802.11g
a wireless network connected to the Internet.with a stock antenna might have a range of 32
The coverage of one or more interconnectedm (120 ft) indoors and 95 m (300 ft)
access points called a hotspot can compriseoutdoors. Range also varies with frequency
an area as small as a single room withband.
wireless-opaque walls or as large as many
square miles covered by overlapping accessAlthough you lose the wires, you're still
points. Wi-Fi technology has served to set uplimited to the base station's range,
mesh  networks.typically 75 to 150 feet indoors and a few
hundred feet outdoors, depending on
Wi-Fi also allows connectivity inequipment, radio frequency, and obstructions.
peer-to-peer (wireless ad-hoc network) mode,
which enables devices to connect directlyPower  drain:
with each other. This connectivity mode can
prove useful in consumer electronics andNetworks using early versions of Wi-Fi
gaming  applications.technology tend to quickly gobble power - a
disadvantage for battery-dependent laptop
Many consumer devices use Wi-Fi. Amongstusers.
others, personal computers can network to
each other and connect to the Internet,Security:
mobile computers can connect to the Internet
from any Wi-Fi hotspot, and digital camerasHere's the downside of providing fast, easy
can  transfer  images  wirelessly.access. Outsiders can sometimes get into your
wireless networks as fast and easily as you
WiFi  Phones:can. Check with hardware vendors about the
latest security precautions and products. The
A WiFi phone is a wireless telephone thatWi-Fi Alliance currently recommends using
looks similar to a mobile phone but placesWi-Fi Protected Access (WPA) technology,
calls via a combination of voice over IP andwhich both authenticates users and encrypts
WiFi rather than via a cellular network. Somedata.



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