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Mini Course

Programming Context-aware Mobile Phones

Thomas Bodin

IT University of Copenhagen

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Tuesday agenda

General Bluetooth concepts Definition Overview Core specifications

Introduction to BlipNet API

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General Bluetooth concepts

Definition A short-range wireless communication technology for voice and data.

Bluetooth communicates via a frequency hopping transceiver in the ISM band. It is based on a low-cost short-range radio link facilitating protected ad hoc connections for stationary and mobile communication.

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General Bluetooth concepts

Overview The Bluetooth wireless connectivity technology was originally

envisioned in 1994 by the Swedish phone equipment maker Ericsson as a way for mobile devices to communicate with each other at short ranges -- up to 30 feet, or 10 meters. In 1998, Ericsson, IBM, Intel, Nokia, and Toshiba formed the Bluetooth Special Interest Group consortium to develop a royalty-free, open specification for short-range wireless connectivity. Since then, more than 2000 companies have joined the Bluetooth SIG, including virtually all manufacturers of phone, computer, and PDA equipment.

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General Bluetooth concepts

Core specifications 2.4 GHz ISM Open band Bluetooth divides the 2.4 GHz frequency band into 79 channels 1

MHz apart (from 2.402 to 2.480 GHz), The frequency hopping is carried out up to 1600 times a second 10 cm-10 meters range (can be extended to 100 m)

8 active devices per piconet (share datarate) Up to 10 piconets in bubble (full datarate)

1 Megabyte per second gross rate Bluetooth defines provisions for three low-power operating modes in

order to conserve battery life: sniff, park and hold mode

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General Bluetooth concepts

Core specifications (continued) 802.15 vs. 802.11

While both Bluetooth and IEEE 802.11b are wireless communication protocols and both operate in the 2.4GHz band, it is important not to visualize Bluetooth as a replacement for 802.11 wireless LAN technology.

The 802.11b protocol is designed to connect relatively large devices with lots of power and speed, such as desktops and laptops. Devices communicate at up to 11 Mbit/sec, at greater distances (up to 300 feet, or 100 meters). By contrast, Bluetooth is designed to connect small devices like PDAs, mobile phones, and peripherals at slower speeds (1 Mbit/sec), within a shorter range (30 feet, or 10 meters), which reduces power requirements.

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General Bluetooth concepts

RF

BB LMPHCIL2CAP

SDP RFCOMM BNEPTCS

OBEX PPP

IP

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General Bluetooth concepts

The radio layer is the physical wireless connection The baseband layer is responsible for controlling and sending

data packets over the radio link The baseband layer maintains Synchronous Connection-Oriented

(SCO) links for voice and Asynchronous Connectionless (ACL) links for data

The Link Manager Protocol (LMP) uses the links set up by the baseband to establish connections and manage piconets.

The Host Controller Interface (HCI) is the dividing line between software and hardware.

The Logical Link Control and Adaptation Protocol (L2CAP) receives application data and adapts it to the Bluetooth format

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General Bluetooth concepts

Profile

RF

BB LMPHCIL2CAP

SDP BNEPTCS RFCOMM

OBEX PPP

IP

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Service Discovery Application Profile

Service Search

LAN Access Profile,Object Push ProfilePAN Profile (NAP)

Service Search

Service Search

RF

BB LMP

L2CAP

SDP BNEPTCS RFCOMM

OBEX PPP

IP

SDAP Profile

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Serial Port Profile

AT Command

RF

BB LMP

L2CAP

SDP BNEPTCS RFCOMM

OBEX PPP

IP

SPP Profile

Serial cable replacement

Basis profile for a series of other profiles

Can be applied directly for data communication

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Dial-Up Networking Profile

DUN- GWDUN Client

Internet

RF

BB LMP

L2CAP

SDP BNEPTCS RFCOMM

OBEX PPP

IP

Dial-UP Networking Profile

Cellular phone acts a wireless modem for connecting to a dial-up internet access server etc.

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Object Push Profile

RF

BB LMP

L2CAP

SDP BNEPTCS RFCOMM

OBEX PPP

IP

OPP Profile

Buisness CardEricssonBluetooth Networks

Business CardMr SmithStreet X, Town Y

Sound

ImageVideo

Game

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BlipServer

Configuration and management of BlipNodes Central security handler Link and session establishment controller Payload gateway for OBEX and SPP data Linux and Windows BlipNet API BlipServer configuration via BlipManager

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BlipManager

Graphical configuration and monitoring of the BlipServer and BlipNodes

Presets for standard configuration Configuration wizards Configuration groups Central controlled security

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BlipNet API

An Open RMI based Java API Monitoring of BlipNet (Event and Poll based) Configuration of dynamic BlipNode settings Send/Receive objects (OBEX) Send/Receive serial data Dynamic Class loading Inquiry start/stop from API Friendly Name lookup event