Bluetooth

for forming Wireless Personal Area Network

cable replacement for personal devices

Not intended for long-running/persistent networks

advanced and promoted by the Bluetooth Special Interest Group

IEEE standardised Bluetooth as IEEE 802.15.1

not based on other standards/technologies

Basic Rate/Enhanced Data Rate (BR/EDR) vs Bluetooth Low Energy (LE)

Maintaining backwards compatibility is a major requirement for the development of new version

ad-hoc wireless network

short-lived

limited range

moderate data rate

called a Piconet

one device is master (usually the most powerfull device)

up to 7 active slaves

slaves are polled by master to transmit data

unlimited connectionless slaves

only receive certain broadcast messages, can not send data

piconet only exists as long as the master is present

devices can chage roles

A BT device can participate in more than one Piconet at once

device has to use Time Multiplexing to switch between the Piconets

A device that is a master in one Piconet can not be a master in another Piconet

A device in more than one Piconet can theoretically be used to route traffic between the Piconets and form a so-called Scatternet

unicast connection between the master and each slave for data transmission

direct connections between slaves are NOT possible

Two broadcast “connections from master to slave

Active Slave Broadcast (ASB)

Connectionless Slave Broadcast (CSB)