Transcript IEEE 802

Bluetooth
발표자 : 현근수
Overview
 wireless protocol
 short-range communications technology
 single digital wireless protocol
 connecting multiple devices
 mobile phones, telephones, laptops, personal
computers, printers, GPS receivers, digital
cameras, and video game consoles over a secure
Uses Bluetooth
 standard and communications protocol
 low power consumption
 short range
Bluetooth vs Wi-Fi in networking (1/2)
 Wi-Fi
 higher throughput
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great distance
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more expensive hardware
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higher power consumption
Bluetooth vs Wi-Fi in networking(2/2)
Same
Wi- Fi
Bluetooth
frequency range
local area network
small scale application
air interface , protocol stack
Ethernet communication
in protocol
USB serial cable link
operating at
a specified bandwidth
not identify other networkin
g standards
Requirement
 PC support
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Bluetooth adapter
others will require an external one in the form of a dongle
multiple devices over a single adapter
 Operating system support
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Bluetooth dongles packaged with their Bluetooth computer devices
(Window)
Bluetooth Stack (Linux)
 Mobile support
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To ensure the broadest support of feature functionality together with
legacy device support
Future of Bluetooth
 Broadcast Channel
 Topology Management
 Alternate MAC PHY
Technical information
Bluetooth protocol stack (1/3)
 Core protocol
 Bluetooth
 Base
Radio
band
 Link Manager Protocol
 Logical Link Control and Adaptation Protocol
 Service Discovery Protocol
Bluetooth protocol stack (2/3)
 Cable replacement protocol
 RFCOMM (Radio frecquency communication )
 Telephony control protocol
 TCS BIN (Telephony control protocol-binary)
Bluetooth protocol stack (3/3)
 Adopted protocols
 PPP (Point-to-Point Protocol)
 TCP/IP/UDP
 OBEX (Object Exchange Protocol)
 WAE/WAP
(Wireless Application Environment/
Wireless Application Protocol)
Communication and connection
 Piconet
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A master device can communicate with up to seven devices
ad-hoc computer network.
Up to 255 further devices can be inactive, or parked.
any time, data can be transferred
the slave can become the master at any time.
The master switches rapidly from one device to another in a round r
obin fashion.
 Scatternet
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connecting two or more piconets
some devices acting as a bridge
 Setting up connection
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Has unique 48 bit address
Scatternet
Pairing
 Transmitter
 cryptographically authenticate the identity of the other device.
 Receiver
 encrypt the data that they exchange over the airwaves
 pairing is preserved, even if the Bluetooth name is
changed.
 Bluetooth 2.1 has an optional "touch-to-pair"
Air interface
 interfering with other protocols that use the 2.45 GHz band
 the Bluetooth protocol divides the band into 79 channels
 changes channels up to 1600 times per second
Security (1/2)
 Confidentiality ,authentication ,Key derivation
 SAFER + block cipher
 Key generation == Bluetooth PIN
 must be entered into both devices. This procedure might be
modified if one of the devices has a fixed PIN,
 e.g. for headsets or similar devices with a restricted
user interface.
Security (2/2)
 Bluejacking
 Bluejacking is the sending of either a picture or a message
from one user to an unsuspecting user through Bluetooth
wireless technology.