wireless-world
Core Specification Addendum 2 was unveiled in December 2011; it contains improvements to the audio Host Controller Interface and to the High Speed (802.11) Protocol Adaptation Layer.
Core Specification Addendum 3 revision 2 has an adoption date of 24 July 2012.
Core Specification Addendum 4 has an adoption date of 12 February 2013.
Bluetooth V4.1
The Bluetooth SIG announced formal adoption of the Bluetooth v4.1 specification on 4 December 2013. This specification is an incremental software update to Bluetooth Specification v4.0, and not a hardware update. The update incorporates Bluetooth Core Specification Addenda (CSA 1, 2, 3 & 4) and adds new features that improve consumer usability. These include increased co-existence support for LTE, bulk data exchange rates—and aid developer innovation by allowing devices to support multiple roles simultaneously. New features of this specification include:
Bluetooth V4.2
Bluetooth v4.2 was released on December 2, 2014. It Introduces some key features for IoT. Some features, such as Data Length Extension, require a hardware update. But some older Bluetooth hardware may receive some Bluetooth v4.2 features, such as privacy updates via firmware.
The major areas of improvement are:
What Is Bluetooth?
Bluetooth is
a specification for the use of low-power radio communications to
wirelessly link phones, computers and other network devices over short
distances. The name Bluetooth is borrowed from Harald Bluetooth, a king
in Denmark more than 1,000 years ago.Bluetooth
technology was designed primarily to support simple wireless networking
of personal consumer devices and peripherals, including cell phones,
PDAs, and wireless headsets. Wireless signals transmitted with Bluetooth
cover short distances, typically less than 30 feet (10 meters) up to 100m.
| Class | Max. permitted power | Typ. range (m) |
|
|---|---|---|---|
| (mW) | (dBm) | ||
| 1 | 100 | 20 | ~100 |
| 2 | 2.5 | 4 | ~10 |
| 3 | 1 | 0 | ~1 |
Bluetooth devices generally communicate at less than 1 Mbps to 24 Mbps,
| Version | Data rate | Max. application throughput |
|---|---|---|
| 1.2 | 1 Mbit/s | >80 kbit/s |
| 2.0 + EDR | 3 Mbit/s | >80 kbit/s |
| 3.0 + HS | 24 Mbit/s | 3.0 + HS |
| 4.0 | 24 Mbit/s | 4.0 LE |
Bluetooth networks feature a dynamic topology called a piconet or PAN. Piconets contain a minimum of two and a maximum of eight Bluetooth peer devices. Devices communicate using protocols that are part of the Bluetooth Specification.
Bluetooth v1.0 and v1.0B
Versions 1.0 and 1.0B had many problems and manufacturers had
difficulty making their products interoperable. Versions 1.0 and 1.0B
also included mandatory Bluetooth hardware device address (BD_ADDR)
transmission in the Connecting process (rendering anonymity impossible
at the protocol level), which was a major setback for certain services
planned for use in Bluetooth environments.
Bluetooth v1.1
- Ratified as IEEE Standard 802.15.1–2002
- Many errors found in the v1.0B specifications were fixed.
- Added possibility of non-encrypted channels.
- Received Signal Strength Indicator (RSSI).
Bluetooth v1.2
Major enhancements include the following:
- Faster Connection and Discovery
- Adaptive frequency-hopping spread spectrum (AFH), which improves resistance to radio frequency interference by avoiding the use of crowded frequencies in the hopping sequence.
- Higher transmission speeds in practice, up to 721 kbit/s, than in v1.1.
- Extended Synchronous Connections (eSCO), which improve voice quality of audio links by allowing retransmissions of corrupted packets, and may optionally increase audio latency to provide better concurrent data transfer.
- Host Controller Interface (HCI) operation with three-wire UART.
- Ratified as IEEE Standard 802.15.1–2005
- Introduced Flow Control and Retransmission Modes for L2CAP.
Bluetooth v2.0 + EDR
This version of the Bluetooth Core Specification was released in
2004. The main difference is the introduction of an Enhanced Data Rate
(EDR) for faster data transfer. The nominal rate of EDR is about 3 Mbit/s, although the practical data transfer rate is 2.1 Mbit/s. EDR uses a combination of GFSK and Phase Shift Keying modulation (PSK) with two variants, π/4-DQPSK and 8DPSK. EDR can provide a lower power consumption through a reduced
The specification is published as Bluetooth v2.0 + EDR, which
implies that EDR is an optional feature. Aside from EDR, the v2.0
specification contains other minor improvements, and products may claim
compliance to "Bluetooth v2.0" without supporting the higher data rate.
At least one commercial device states "Bluetooth v2.0 without EDR" on
its data sheet.
Bluetooth v2.1 + EDR
Bluetooth Core Specification Version 2.1 + EDR was adopted by the Bluetooth SIG on 26 July 2007.
The headline feature of v2.1 is secure simple pairing (SSP): this
improves the pairing experience for Bluetooth devices, while increasing
the use and strength of security. See the section on Pairing below for more details.
Version 2.1 allows various other improvements, including "Extended
inquiry response" (EIR), which provides more information during the
inquiry procedure to allow better filtering of devices before
connection; and sniff subrating, which reduces the power consumption in
low-power mode.
Bluetooth v3.0 + HS
Version 3.0 + HS of the Bluetooth Core Specification was adopted by the Bluetooth SIG on 21 April 2009. Bluetooth v3.0 + HS provides theoretical data transfer speeds of up to 24 Mbit/s,
though not over the Bluetooth link itself. Instead, the Bluetooth link
is used for negotiation and establishment, and the high data rate
traffic is carried over a colocated 802.11 link.
The main new feature is AMP (Alternative MAC/PHY), the addition of 802.11
as a high speed transport. The High-Speed part of the specification is
not mandatory, and hence only devices that display the "+HS" logo
actually support Bluetooth over 802.11 high-speed data transfer. A
Bluetooth v3.0 device without the "+HS" suffix is only required to
support features introduced in Core Specification Version 3.0 or earlier Core Specification Addendum 1.
Bluetooth v4.0
General improvements in version 4.0 include the changes necessary to
facilitate BLE modes, as well the Generic Attribute Profile (GATT) and
Security Manager (SM) services with AES Encryption.Core Specification Addendum 2 was unveiled in December 2011; it contains improvements to the audio Host Controller Interface and to the High Speed (802.11) Protocol Adaptation Layer.
Core Specification Addendum 3 revision 2 has an adoption date of 24 July 2012.
Core Specification Addendum 4 has an adoption date of 12 February 2013.
Bluetooth V4.1
The Bluetooth SIG announced formal adoption of the Bluetooth v4.1 specification on 4 December 2013. This specification is an incremental software update to Bluetooth Specification v4.0, and not a hardware update. The update incorporates Bluetooth Core Specification Addenda (CSA 1, 2, 3 & 4) and adds new features that improve consumer usability. These include increased co-existence support for LTE, bulk data exchange rates—and aid developer innovation by allowing devices to support multiple roles simultaneously. New features of this specification include:
- Mobile Wireless Service Coexistence Signaling
- Train Nudging and Generalized Interlaced Scanning
- Low Duty Cycle Directed Advertising
- L2CAP Connection Oriented and Dedicated Channels with Credit Based Flow Control
- Dual Mode and Topology
- LE Link Layer Topology
- 802.11n PAL
- Audio Architecture Updates for Wide Band Speech
- Fast Data Advertising Interval
- Limited Discovery Time
Bluetooth V4.2
Bluetooth v4.2 was released on December 2, 2014. It Introduces some key features for IoT. Some features, such as Data Length Extension, require a hardware update. But some older Bluetooth hardware may receive some Bluetooth v4.2 features, such as privacy updates via firmware.
The major areas of improvement are:
- LE Data Packet Length Extension
- LE Secure Connections
- Link Layer Privacy
- Link Layer Extended Scanner Filter Policies
- IP connectivity for Bluetooth Smart devices to become available soon after the introduction of BT v4.2 via the new Internet Protocol Support Profile (IPSP).
- IPSP adds an IPv6 connection option for Bluetooth Smart, to support connected home and other IoT implementations.
