발표자 : 현근수

Bluetooth

Overview

wireless protocol short-range communications technologysingle digital wireless protocolconnecting 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

great distance

more expensive hardware

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 networking standards

Requirement

PC support Bluetooth adapter others will require an external one in the form of a dongle multiple devices over a single adapter

Operating system support Bluetooth dongles packaged with their Bluetooth computer

devices (Window) Bluetooth Stack (Linux)

Mobile support 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 protocolBluetooth RadioBase bandLink Manager ProtocolLogical Link Control and Adaptation

ProtocolService 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 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 robin fashion. Scatternet

connecting two or more piconets some devices acting as a bridge

Setting up connection 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 cipherKey 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.