Bluetooth technology was first conceived at Ericsson in 1994 with the intent to replace the litany of cables and cords connecting computer peripherals with an RF medium. Intel and Nokia also joined in with the intent to wirelessly link cell phones to computers in a similar manner. The three formed an SIG in 1996 at a conference held at the Ericsson plant in Lund, Sweden. By 1998, there were five members of the Bluetooth SIG: Intel, Nokia, Toshiba, IBM, and Ericsson. That year, version 1.0 of the Bluetooth specification was released. Version 2.0 was later ratified in 2005 when the SIG had over 4000 members. In 2007, the Bluetooth SIG worked with Nordic Semiconductor and Nokia to develop Ultra Low Power Bluetooth, which now goes by the name Bluetooth Low Energy (BLE). BLE brought an entirely new segment to the market in devices that could communicate using a coin cell battery. By 2010, the SIG released the Bluetooth 4.0 specification, which formally included BLE. Currently, there are over 2.5 billion shipping Bluetooth products and 30,000 members in the Bluetooth SIG.
Bluetooth has been used extensively in IoT deployments for some time, being the principal device when used in low energy mode (LE) for beacons, wireless sensors, asset tracking systems, remote controls, health monitors, and alarm systems.
Throughout its history, Bluetooth and all the optional components have been under GPL license and are essentially open source.
The revision history of Bluetooth as it has grown in features and abilities is shown in the following table:
Revision |
Features |
Release date
|
Bluetooth 1.0 and 1.0B |
Basic rate Bluetooth (1 Mbps)
Initial version released. |
1998 |
Bluetooth 1.1 |
IEEE 802.15.1-2002 standardized
1.0B specification defects resolved
Non-encrypted channel support
Received Signal Strength Indicator (RSSI) |
2002 |
Bluetooth 1.2 |
IEEE 802.15.1-2005
Rapid connection and discovery
Frequency hopping spread spectrum (AFH) Host controller interface (three-wire UART)
Flow control and retransmission modes |
2003 |
Bluetooth 2.0 (+EDR optional) |
Enhanced Data Rate Mode (EDR): 3 Mbps |
2004 |
Bluetooth 2.1 (+EDR optional) |
Secure Simple Pairing (SSP) using public key cryptography with four unique authentication methods Extended Inquiry Response (EIR) allows for better filtering and reduced power |
2007 |
Bluetooth 3.0 (+ EDR optional) (+HS optional) |
L2CAP enhanced retransmission mode (ERTM) for reliable and unreliable connection states
Alternate MAC/PHY (AMP) 24 Mbps using 802.11 PHY
Unicast connectionless data for low latency
Enhanced power control |
2009 |
Bluetooth 4.0 (+ EDR optional) (+HS optional) (+LE optional) |
AKA BluetoothSmart
Introduced Low Energy mode (LE)
Introduced ATT and GATT protocols and profiles
Dual mode: BR/EDR and LE mode
Security manager with AES encryption |
2010 |
Bluetooth 4.1 |
Mobile wireless service (MWS) coexistence
Train nudging (coexistence feature)
Interlaced scanning (coexistence feature)
Devices support multiple simultaneous roles |
2013 |
Bluetooth 4.2 |
LE secure connections
Link layer privacy
IPv6 support profile |
2014 |
Bluetooth 5.0 |
Slot availability masks (SAM) 2 Mbps PHY and LE LE long range mode LE extended advertising modes Mesh networking |
2016 |