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Mobile
phones, headsets, PDA's and portable
computers
can communicate and send data to
each other
without wires or cables to link to
devices
together. The name of Bluetooth derived from
the name of
an English king Harold Bluetooth.
It a low
cost, low power, radio technology,
which is
particularly suited to the short range
Personal
Area Network (PAN) application.
Bluetooth
Special Interest Group is authorized
to develop
its specifications & license.
Features:-
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• It
operates in the 2.4GHz frequency band
without
having a license for wireless
communication.
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• Up to
10-100 meters data can be transfer
in real
time.
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• Close
proximity & accuracy is not required
for
Bluetooth as in case of infrared data (IrDA)
communication device. Bluetooth does
not
suffer from
interference from obstacles such
as walls
while infrared suffers due to obstacles.
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• Bluetooth
supports both point-to-point and
point-to-multipoint wireless
connections
without
cables between mobile phones and
personal
computers.
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• Data
transfer rate of blue tooth varies from
version to
version. Data rate of 1 Mbps for
Version 1.2
Up to 3 Mbps for Version 2.0.
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Then major
parts of Bluetooth system are
RF
transceiver, base band, and protocol stack.
Bluetooth is
used for small-area networking
without user
intervention.
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Due to
extremely low transmission power in
Bluetooth
technique battery power is saved.
It is a
networking standard that works at two
levels:
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• Physical
level.
• Protocol
level
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Due to these
levels mobiles have to agree on
these levels
when bits are sent. It decides the
amount of
data to be sent at a time, and how
the parties
in a conversation can be sure that
the message
received is the same as the message
sent.
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Bluetooth
networking transmits data through
low-power
radio waves. It can connect up to
eight
devices simultaneously. With in the range
of about ten
meters you must think that the
devices will
not interfere with each other.
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Bluetooth
solved the problem of devices
interference
while sending the data by using
the
technique of Spread-Spectrum Frequency
Hopping due
to which devices may transfer
data at the
same frequency at the same time.
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The question
rises here is how Bluetooth send
the same
data using same frequency band
without
devices interferences? In Bluetooth
technique,
transmitters change frequencies
1,600 times
in every second. In this way
devices can
make full use of a limited band
of the radio
spectrum.
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When
Bluetooth devices came into the range
of each
other, conversations take place
automatically. This conversation
automatically
determines
whether they have the data to share
or not.
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In this way
Bluetooth devices not only share
the data but
also control the data to be transferred. When the
connection
is established, the devices either they are part
of a
computer system or a network, Bluetooth
systems
create a personal-area network.
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The
technology used in Bluetooth also provides
security in
three ways:
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•
Pseudo-random frequency hopping,
• Authentication,
•
Encryption.
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Frequency
hops make it difficult for anyone
to
eavesdrop. Authentication allows a user to
limit
connectivity to specified devices.
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Encryption
uses secret keys to make data
intelligible
only to authorized parties. Service-
level
security and device-level security work
together to
protect Bluetooth devices from
unauthorized
data transmission.
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Security:-
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Many serious
problems create only due to
improper
security issues. Some of them are
given
below:
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• Blue
jacking
• Blue bugging
• Car
Whisperer
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Blue
Jacking:-
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It is used
to send a business card in the form
of text
message via Bluetooth to other users.
It should be
noted that the distance between
two users is
not more than 10 meters. If the
user doesn't
found the proper text, he should
add the
contact to his phone book.
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After saving
his contact in his address book
retry to
send the same message. In this way
the user can
get business card from other user
via
Bluetooth. It’s all because of the known
destination
from where the massage is being
coming.
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Blue
Bugging:-
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Due to this
hackers can access user’s phone.
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It not only
access one’s mobile phone, but
also use its
features including placing call,
messaging.
Even though the user doesn't realize
it’s
happening.
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Car
Whisperer:-
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Car whisper
is a type of software due to which
hackers can
send and receive audio file from a
Bluetooth-enabled car stereo.
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