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8/8/2019 Blue Tooth Seminar
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PRESENTED BY :
SOURAV ROY
DEBALINA GHOSH
DEEPANWITA SAR
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10/27/2010 copyright 2010 debalina ghosh,sourav roy, deepanwita sar 2
What is Bluetooth? ***this slide should be
Bluetooth Features«. EDITED to purpose
History Accordingly.
Characteristics««.
Architecture
Bluetooth Circuit
Bluetooth Layers [Radio Layer,Baseband Layer,L2CAP]
Bluetooth Protocol Stack
Bluetooth operational State
Application Of Bluetooth
Security of Bluetooth
Advantage & Disadvantage of Bluetooth
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WHAT IS BLUETOOTH ? Bluetooth is a short range (10-100 m) and low-cost wireless
network system to replace cables and give RF connectionbetween consumer devices.
10/27/2010 3copyright 2010 debalina ghosh,sourav roy, deepanwita sar
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Bluetooth features at a glance
10/27/2010 copyright 2010 debalina ghosh,sourav roy, deepanwita sar 4
Supports up to 8 simultaneous links in a
piconetTopology Goes through walls, bodies, clothes, ...Flexibility
1 MSPS, 721 KbpsData rate
0.1 Watts active power Power
25 mm × 13 mm × 2 mm, several gramsSize/Weight
Long term $5 per endpointCost
10 meters or less; up to 100 meters with PARange
Intended to work worldwideUniversal
Very, link layer security, SS radioSecurity
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IN THE BEGINNINGuuu
When does it appear? 1994 ± Ericsson study on a wireless technology to link mobile
phones & accessories. 5 companies (Ericssn,Nokia,IBM,Toshiba & Intel) joined to form the
Bluetooth Special Interest Group (SIG) in 1998 named.
First specification released in July 1999.
Why this name?It was taken from the 10th century Danish King Harald Blatand who
unified Denmark and Norway. Although it¶s popularly believed that King
Harald had a blue tooth, and various stories explain how this came about,
it¶s more likely that the Bluetooth name is the English derivative of the
original Viking word, Blâtand. The Bluetooth name was chosen for the
wireless technology because its developers and promoters hope it will
unite the mobile world, just as King Harald united his world.
.
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CHARAC TERISTIC S OF BLUETOOTH
8 devices to communicate in a localnetwork called a Piconet, also known as a PersonalArea Network or PAN
Because of its low power consumption, its range islimited to 10 m.
However, range can be increased to 100 m byemploying a scatternet topology or a higher poweredantenna
Three classes of Bluetooth devices-Class 3 radios ± have a range of up to 1 meter or 3
Feet.-Class 2 radios ± most commonly found in mobiledevices ± have a range of 10 meters or 30 feetClass 1 radios ± used primarily in industrial usecases ± have a range of 100 meters or 300 feet
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AR CHITE C TURE OF BLUTOOTHOne of which is called PRIMARY
the rests are called SECONDERIES.
A Piconet or Small net can have
eight Stations.
all the seconderies syncronize
thiers clocks & hopping sequences
to primary.
An aditional eight seconderies canbe in the PARKED State.
Pi conets can be
combined to form
SCATTERNET.
A secondery Station in
one Piconet can be the
Primary in another
Piconet.
A station can be a10/27/2010 7copyright 2010 debalina ghosh,sourav roy, deepanwita sar
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BLOCK DIAGRAM OF BLUETOOTH CIR CUIT :
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BLUETOOTH LAYERS
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BLUTOOTH -RADIO LAYER
The radio layer is equivalent to the
Physical layer to the Internet Moel.
Blutooth uses a 2.4GHz ISM band
divided into 79 channels of 1 MHz
each.
Fc = 2402+n {n=0,1,2««..78}
Example :- The first Channel uses carrier
frequency 2402 MHz & the second channel
uses 2403MHz .
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FRAME FORMAT OF BLUE TOOTH
A Frame in the baseband layer can be 3 types
1.One ±slot can lasts for 366s.2. three- slot can lasts for 1616s.
3. Five ± slot can lasts for 2866s.
The above fig shows the format of three frame types.
There are three kinds of access codes. Channel Access Code (CAC) is
used to identify thepiconet.
Device Access Code
(DAC) is used for specialsignaling procedures, suchas paging and response to
pagingBluetooth device has a
unique address calledBD_ADDR. It contains twoparts: company ID which isunique across the world,
and device ID which isunique within the products
of the companyThe preamble is simply a
fixed ³0101´ or ³1010´sequence depending onwhether the LSB of the
following sync word is ³0´or ³1´.
AM_ADDR: temporary address assigned to active members of
the piconet, used on all packets in both direction sent
between the master and the addressed slave. An all-zero
AM_ADDR is used to broadcast to all slaves.
TYPE: type of packet. There are 12 types of packets
for each SCO and ACL physical links, and four typesof common control packets for both.
FLOW: for flow control.
ARQN: for ACK.
SEQN: contains sequence number for packet
ordering.
HEC: header error check for header integrity.
Payload
There can be two types of payload: voice and data. SCO
packets only have voice field, while ACL packets only havedata field.
.
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LOGICAL LINK CONTROL &
ADAPTATION PROTOCOL :-
U pppper Protocol
Layer
L2CAP Layer
Lower Protocal
Layer
U pppper Protocol
Layer
L2CAP Layer
Lower Protocal
Layer
Client Server
L2CA_ req L2CA_ req
L2C
A res L2CA _res
LPrequest
LPrequest
LPresponse
LP response
Protocol Requirements :-
Multiplexing-Segmentation & Reassemblyv
Quality of ServiceGroups
. L2CAP layer servesupper layer by transmittingdata over channels
A channel is setup in thefollowing procedure:1. Connection
2. Configuration3. Disconnection10/27/2010 12copyright 2010 debalina ghosh,sourav roy, deepanwita sar
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BLUETOOTH PROTOCOL STACK
Baseband: The Baseband and Link
Control Layer enables the RF link
Bluetooth units in a piconet.
Link Manager Protocol (LMP): The link
manager protocol is responsible for
setting up link channels between
Bluetooth devices after performingsecurity methods
Logical Link Control and Adaptation
Protocol (L2CAP): L2CAP packets carry
payloads which are carried to the upper
layer protocols.
Service Discovery Protocol (SDP):
Using SDP, device information, services
allowed and characteristics of the
services are queriedCable Replacement Protocol
(RFCOMM): RFCOMM is a serial line
emulation protocol.
Telephony Control Protocol: The
Telephony Control - Binary (TCS Binary)
and Telephony Control ±
Adopted Protocols: Bluetooth also
supports PPP, TCP/UDP/IP, OBEX and
WAP .10/27/2010 13copyright 2010 debalina ghosh,sourav roy, deepanwita sar
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BLUETOOTH OPERATIONAL
STATE Stand by : Initial state. Inquiry / Sniff :- Master
sends an inquiry packet.Slavesscan for enquiries& respondswith their clk after a random
delay.Page :Master in page state
invite devices to join thepiconet.Page messages aresent in 3 consecutive slots.
Master inform its slave aboutits clock & address to join in
that piconet.Connected : A short 3 bit
logical address is assigned. Transmit.
THREE INACTIVE STATES :
HOLD : No ACL. SCO continues
Node can do something else:
scan,page,inquire.
Sniff : Low power mode. Slaves listen
only after fixed intervals.
Park :- Very low power mode.Gives
up its 3 bit active member address &
gets an 8- bit parked member address.
Packets for parked station are
broadcast to 3 bit zero address.
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Low energyconsumption
wireless.
Accessiblefrom
everywhere.
Sharevoice &
data
automatic
inexpensive
Advantages of bluetooth:-
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APPLICATIONS APPLICATIONS
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BBluetooth Devicesluetooth Devices
Bluetooth will soon be enabled in everything
from:
Telephones
Headsets
Computers
Cameras
PDAs
Cars
Etc «
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APPLICATIONS APPLICATIONS
The wireless communication between the input and outputdevices of the personal computers like the mouse, keyboard andprinter is an example of Bluetooth.
The communication between a mobile and a hands-free headset is
another popular example of wireless Bluetooth. Use of Bluetooth is to transfer files between devices with OBEX.
Use of Bluetooth to transfer contact details, reminders,appointments dates between devices with OBEX.
Bluetooth enabled advertising hoardings can receive and display the
smaller advertisements by using technology. Removal of traditional wires in test equipments, bar code scanners,
traffic control devices, GPS receivers and medical equipment is arevolutionary change.
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BBluetooth Productsluetooth Products
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Bluetooth Mice & Keyboards
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BBluetooth Productsluetooth Products
Bluetooth Flash Card & Modem
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BBluetooth Productsluetooth Products
Bluetooth PDAs(Personal Data Assistant)
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BBluetooth Productsluetooth ProductsBluetooth-enabled Cell Phone
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Bluetooth MP3 Players
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BBluetooth Productsluetooth Products
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Bluetooth Headsets
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BBluetooth Productsluetooth Products
Bluetooth Medical Devices
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Bluetooth
Access Points
Bluetooth Projectors
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Bluetooth Adapters for
non-Bluetooth
computersBluetooth Cameras
BBluetooth Productsluetooth Products
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APPLICATIONS APPLICATIONSOTHER««««
Data synchronization need never again be a problem as your Bluetooth enabled PDA, PC or laptop all talk to each other andupdate their respective files to the most recent ones.
Travelling in a plane, a person may write but not send e-mail. Whenthe plane touches down the Bluetooth enabled laptop willcommunicate with the user's phone and will automatically sendthem.
Mice and keyboards will identify themselves to the computer withoutintervention, or could also be used to command TVs, videos or hi-fisat the touch.
e-mails and read those you select in the mobile phone's display.
Use e-mail while your laptop is still in the briefcase! When your laptop receives e-mail, you'll get an alert on your mobile phone. Youcan also browse all incoming data.
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FUTURE:: FUTURE::
WIRELESS WORLD
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Bluetooth¶s Future
The future of this technology becoming a standard is likely
With a strong industry pushing behind it, success is inevitable.
Bluetooth will soon be known as Bluetooth 1.2. as they are trying todevelop the product to better fulfill the needs of consumers
Often, with new technology, early changes mean reconstruction. NotWith Bluetooth, instead, there will be an improvement to the existingstandard.
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CONTENT
General Security Issues InWireless
Network.
Bluetooth Security Modes
Bluetooth Security Infrastructure.
WeaknessesWith Bluetooth
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GENERAL SECURITY ISSUES
INWIRELESS NETWORK
In a Wireless environment as every bit is on air so security concern is HIGH.
3 main issues regarding Wireless NetworkSecurity are- ± Confidentiality
To send information across the network in such a way thatonly the intended recipient (s) can read it.
± Availability The network available to users whenever it is supposed to
be. ± Data Integrity
Transferring data to the recipient (s) intact.
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BLUETOOTH SECURITY MODES
In Bluetooth, there are three security modes- ± Security Mode 1: Non-Secure
± Security Mode 2: Service Level Enforced Security
± Security Mode 3: Link Level Enforced Security
The 3 above mentioned modes are described in TABLE-
1 in next slide.
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TABLE-1
MODE DESCRIPTION
1 In this MODE, the device does not implement any securityprocedures, and allows any other device to initiateconnections with it.
2 In this MODE security is enforced AFTER the link is
established , allowing higher level applications to run more
flexible security policies.3 In this MODE security controls such as AUTHENTICATION
andENCRYPTION
are implemented at theBaseband
level BEFORE the connection is established . In thisMODE, BLUETOOTH allows different security levels to be
defined for DEVICES and SERVICES.
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BLUETOOTH SECURITY
INFRASTRUCTURE
COVERED DOMAINS-----
1.SECURITY ENFORCED IN MODE-2.
2.SECURITY ENFORCED IN MODE-3.
3. SECURITY PROTOCOLS
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SECURITY ENFORCED IN MODE-2. In security mode 2, security is handled by
higher level applications rather than at the link
level, and is enforced after the communication
is established .
As Bluetooth uses the RFC
OMM protocol it isable to use existing protocols such as TCP, UDP
andWAP, and can use the security measuresbuilt into these.
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SECURITY ENFORCED IN MODE-3. In security mode 3, security is enforced before a
communications link is established . Security inBluetooth, like in other networks is based onauthentication and encryption.
In Bluetooth security there are four main identifiers- ± 48 bit unique IEEE Bluetooth device address (BD_ADDR).
± 128 bit Link key, used for authentication. ± 8-128 bit symmetric encryption key.
± 128 bit random numbers (RAND) generated as required.
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SECURITY PROTOCOLS
BLUETOOTH offers 2 basic S ecurity
Protocols- ± AUTHENTICATION
± ENCRYPTION
Among above two AUTHENTICATI
ONis mandatory i.e. it must be inherited by
the BLUETOOH device.
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AUTHENTICATION
To authenticate devices in Bluetooth, a link key isgenerated for the connection, followed by a
challenge-response strategy to ensure that theclaimant device knows the link key.
There are four types of link key defined in theBluetooth specification:
± UNIT KEYS ± INITIALISATION KEYS
± COMBINATIONAL KEYS
± MASTER KEYS
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CONT..
In addition, Bluetooth defines four algorithms for key
generation and authentication-
± E1
± E21 ± E22
± E3
They are all based on the SAFER+ block cipher
algorithm.
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GENERATION OF UNIT KEY (KA)
E21
RAND A
BD_ADDR A
K A
DEV
ICE A
(128 bits)
(48 bits)
(128 bits)E21: CRYPTOGRAPHIC
HASH FUNCTION
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AUTHENTICATION PROCESS
Link key generation
KLINK
PINRandom #
SRES¶SRES ACO¶ ACO
Encryption key generation
SRES¶
BD_ADDRB
CHECKSRES = SRES¶
E1
(SAFER+)BD_ADDRB
KLINK
AU_RAND
E1
(SAFER+)BD_ADDRB
KLINK
AU_RAND
A (Verifier) B (Claimant)
AU_RAND
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E0
BD_ADDR A
clock A
KC¶
Kcipher
Kcipher
Kcipher
data A-B
dataB-A
E0
BD_ADDR A
clock A
K¶C¶
K¶cipher
K¶cipher
K¶cipher
data A-B
dataB-A
data
A B
=
ENCRYPTION
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WITH BEST REG ARDSTO PROF. SAIKAT
BHTTACHARYA