What is Bluetooth and how does it work?
Bluetooth is a radio technology used to make a direct connection and transfer data between compatible products.
It is now used across dozens of product categories and has applications ranging from simple audio streaming, to direct remote control of appliances.
Compared to legacy wireless data technologies such as infra-red, Bluetooth offers low power consumption and broad compatibility across may product categories. There have been many upgrades to the Bluetooth specification over the years and it is a good idea to check which specification your potential purchase has:
- Bluetooth 1.2 - Transmissions speeds up to 721kb per second. Not many devices will use this any more.
- Bluetooth 2.0 (EDR) - Transmissions speeds up to 2.1Mbit per second
- Bluetooth 2.1 (EDR) - The same speed as 2.0, with improved pairing capability and reduced power consumption in certain modes
- Bluetooth 3.0 (HS) - Now implemented in most devices, this has speeds above 400Mbit / s, using ultra-wideband radio signalling
- Bluetooth 4.0 (LE) - Rather than improve speed and bandwidth, 4.0 focussed and massively reducing power consumption
- Bluetooth 4.1 (LE) - An incremental update to Bluetooth 4.0. Updated specification and increased compatibility with other technologies
- Bluetooth 4.2 (LE) - Further enhancements for Internet of Things (IoT) equipment, including better Low Energy support, IPv6 and data packet length
- Bluetooth 5.0 (LE) - Further enhancements for (IoT). Max speed up to 2Mbit/s, plus 4x range increase & 8x broadcasting capacity
Bluetooth is a short range radio standard, the distance of which varies depending on implementation. In some cases this reach up to 100 metres, with an expected usual range of 10 metres in most scenarios.
The uses for Bluetooth are considerable. The most common is audio streaming, from say a smartphone to a Bluetooth headset or car stereo. There are though countless ways in which owning a Bluetooth enabled device could be advantageous:
- Transferring data from phone to phone (images, contact details etc.)
- Synchronising your mobile device wirelessly with a desktop computer / laptop
- Printing documents via a Bluetooth printer
- Connecting wireless keyboards and mice
Bluetooth does require line of sight and so offers greater flexibility when connecting two devices. As long as they are within range they will be able to communicate.
Bluetooth devices need to pair with each other to communicate.
Usually this requires putting both devices into a pairing mode. Once they have 'discovered' each other, trading a PIN code is generally how a connection is finalised.
Following an inital pairing, Bluetooth devices should 'remember' each other, unless settings are reset.
Pairing is a short process and all Bluetooth devices should come with a manual explaining the process and the required PIN code.
Bluejacking is a term used to describe the unsolicited sending of text messages, images and sounds to a Bluetooth enabled device.
If you leave your device with Bluetooth on and 'discoverable' to other Bluetooth equipment, you could be liable to receive unsolicited files.
The risk is minimal in the modern landscape, although does still exist and so at the highly security conscious should take steps to avoid it.
It’s not Wi-Fi
Bluetooth should not be confused with Wi-Fi.
Wi-Fi has greater range and higher power requirements, and is most commonly used to provide access for personal computers into a wider network (possibly, but not always, with Internet access).
Bluetooth is best suited for small mobile devices with limited requirements.
If you are wondering why this technology is called Bluetooth here is the answer: it was named after Harald Bluetooth who was the king of Denmark in the 900’s. He united Denmark and a part of Norway during his reign and thus the link is made. The reason his name was chosen is because of the influence companies in the Nordic region have on this type of technology.