Bluetooth has become widely popular and a standard feature of any mobile device. Bluetooth is convenient, versatile and it has by now become easy and robust to handle. Bluetooth is a technology standard which was developed according to IEEE 802.15.1 in the 1990s for the wireless data exchange between devices over short distances. The wireless network which is the basis for Bluetooth was largely developed by the Dutch Professor Jaap Haartsen and the Svedish Professor Sven Mattisson for Ericsson. Additional components of today’s standard were provided by Nokia, IBM, Toshiba and Intel, who formed the Bluetooth Special Interest Group in 1998. Today, Bluetooth facilitates communication and data exchange or transportation between all kinds of electronic devices. One of Bluetooth’s greatest advantages lies in its platform-independent standard: there are no compatibility problems between, say, Android or iOS devices.
WPAN stands for Wireless Personal Area Network (also referred to as Wireless Individual Area Network or Wireless Domestic Area Network) and covers wireless networks with a small reach of a few dozen meters maximum. Bluetooth covers up to 100 meters with a class 1 network outside, making transmissions from point-to-point, ad-hoc-networks and piconets (technical term for Bluetooth-networks) possible.
Bluetooth?
The name „Bluetooth“ is derived from the Danish King Harald Bluetooth whose outstanding communication skills enabled him to reconcile and eventually unite antagonistic parts of Norway and Denmark. The logo shows the Norse runes for H(arald) and B(luetooth) as a further tribute to this king.
Security
The Bluetooth-standard is seen as relatively safe, as long as the connection is secured by means of a multilevel dynamic key management and the PIN contains more than four digits. As any mode of digital data exchange, Bluetooth offers no absolute security, but the fact that Bluetooth is in general not used statically but while moving in and through public space renders it difficult for hackers to receive a stable signal which they might hack. The weak point here is the pairing, which involves the transmission of key information for split seconds.
Pairing
In the Bluetooth context, pairing refers to connection of two or more devices. For devices to be paired, they need to be switched on and visible to each other. Any device (the master) can coordinate the connection to another, responding device (the slave). As soon as Bluetooth-devices are activated, the individual Bluetooth-controller identify an individual, distinctive, 48 Bit long MAC-address within two seconds. Unconnected devices in standby-mode scan messages in intervals of 2,56 seconds (scan mode – shorter intervalls require more energy). Thereby, they control 32 frequencies transmitting a Bluetooth signal. Connection is even easier if both devices are NFC-enabled (Near Field Connectivity). In that case, pairing becomes dispensable as the connection can be set up by briefly holding the devices together at their NFC-contact points.
Unlimited Functionality.
Bluetooth-enabled functions depend on the respective device: almost all Bluetooth-earphones can be used as a headset if paired with a smartphone, and support the control off all phone- and player functions. Thus, Bluetooth can even support control functions which enable users to operate devices via natural language input – provided that such devices are equipped with intelligent voice recognizers and NLU-components: “Compile a list of Heavy-Metal songs from the 90s and play in shuffle mode.” Data transmissions are also possible, e.g., for internet use in a non-connected car.
With the Standard Bluetooth 3.0 and Bluetooth V4.0 Low Energy, sending and receiving will be possible even without connection – which is especially important for the use of iBeacons or blukii-Beacons which can be used to transmit data or for indoor-localization. A Beacon signal can be received by smartphones, tablets and pcs with a Bluetooth Smart (Bluetooth 4.0) interface. Apps on the devices automatically connect the signals with information from the cloud, the internet or from the receiving device directly and display them on the smartphone, tablet or pc. With such Beacons, museums can display content directly on their visitor’s smartphones, depending on their location in relation to the rooms or exhibits. In a similar vein, customers can be informed of special offers they are interested in or when they are passing a shop selling the respective product.
Another interesting use case is the Notebook-Protector by blukii which is able to automatically recognize the user through a Bluetooth-Smart-Sensor and which locks the computer automatically if the user moves away – and unlocks it upon the owner’s return. An acoustic and visual alarm sets off if someone else touches the notebook, the keyboard or mouse while it is locked, furthermore, an alert email is sent simultaneously to a specified address, and a virtual security guard takes and sends photos from the notebook’s environment.
Bluetooth LE offers a vast range of potential use cases for short-distance data exchange and communication– which need yet to be explored.