발표자 : 현근수 Bluetooth

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  great distance  more expensive hardware  higher power consumption

Bluetooth vs Wi-Fi in networking(2/2) SameWi- FiBluetooth frequency rangelocal area networksmall scale application air interface, protocol stackEthernet 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 protocol  Bluetooth Radio  Base 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  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 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.