The latest standard for the Bluetooth wireless networking protocol, Bluetooth 4.2, was released last week. Bluetooth 4.2 opens up new deployment options for users of Bluetooth Low Energy (BLE) devices, including Bluetooth beacons, as well as other products containing BLE radios. These include intelligent light bulbs, electronically controlled door locks, security sensors, or wearables sensors issued to medical patients and used to track such factors as heart rate or respiration, as part of home health-care systems. The updates are focused on connectivity, security and privacy features.
Under the current (4.1) Bluetooth standard, users can only connect to Bluetooth devices through an application, but 4.2 includes an Internet Protocol Support Profile (IPSP), enabling users to assign an Internet Protocol (IP) address (complaint with the IPv6 or 6LoWPAN standard) to a Bluetooth device. This way, that device can communicate directly through a router, which means a user can control it through the cloud rather than via an application.
Pulling data from or sending commands to a Bluetooth device via Wi-Fi is computationally taxing and uses a considerable amount of energy, says Errett Kroeter, the Bluetooth Special Interest Group (SIG)’s senior director of marketing. That means that Bluetooth devices currently need to be plugged into a power source to be used this way—ruling out myriad applications for Bluetooth beacons, which are small wireless Bluetooth radios that are generally battery-powered, though some are designed to be powered by a USB port, or for BLE-powered wireless sensors used in building security or automation applications, or for home health-care applications. Addressing Bluetooth beacons via IPv6 or 6LoWPAN requires a fraction of the energy that a device needs to communicate via Wi-Fi, and means that, say, beacons could be used for asset tracking or access control without the need for a separate application to manage those devices.
In terms of how Bluetooth 4.2 will impact businesses, being able to connect directly to the Internet, rather than first having to send data to consumers’ smartphones, should be a boon for makers of Bluetooth-enabled “smart home” devices, as consumers who have been watching and waiting on deploying such systems within their homes might now be swayed to buy. The adoption of the 4.2 specification would also make Bluetooth-enabled smart home products more competitive with similar devices that employ the Thread Protocol, released earlier this year and developed by a group of companies including Nest, ARM and Samsung. The Thread Protocol already supports IP-addressing—as well as mesh networking, which the Bluetooth 4.2 does not include.
For asset-tracking applications, such as using Bluetooth beacons to track equipment inside a facility, or for access-control applications, such as integrating Bluetooth radios into employee badges, being able to communicate with these radios via a wireless local area network (LAN) will make them less complicated to deploy and manage.
The 4.2 standard also makes it possible to secure transmissions to Bluetooth devices using the Federal Information Processing Standard (FIPS) AES 128-bit encryption key. “This standard was partially deployed in previous [BLE] standards, but there was a propriety encryption key,” Kroeter says. “We moved to the industry-standard key for better security, and because it will bring the security standard for Bluetooth Low Energy devices into parity with the Bluetooth Classic standard.”
A new privacy feature is designed to ensure that consumers’ smartphones remain completely hidden, such that the beacons installed in public spaces cannot detect them unless an owner has downloaded an application allowing data exchange. The phone’s Bluetooth radio accomplishes this by hashing the transmission of the phone’s MAC address when responding to a ping from a beacon—unless that beacon identifies itself as part of an application that the user had already installed on the phone. (Under 4.1 and earlier BLE standards, a phone will respond to a ping from any Beacon by transmitting its MAC address.)
Lastly, for BLE devices, the 4.2 standard supports a data transfer rate that is 2.5 times faster than that enabled by the 4.1 standard, a tenfold improvement in the size of data packets that can be transferred. These upgrades might not seem very useful to consumers (“Downloading data from your Fitbit might take 4 seconds instead of 10 seconds,” Kroeter suggests), but they should reduce the likelihood of transmission errors, while also helping to decrease battery consumption.
The privacy and security upgrades will be available through a firmware upgrade as device manufacturers (such as handset makers, or Bluetooth wearable sensor or security sensor vendors) make them available. The IP-address upgrade, data transfer and increased data packet transfer features, however, will require hardware upgrades, and will thus only be rolled out as updated, or as new hardware products are released into the marketplace.
While these new features may enable more secure, easily managed deployments of systems that rely on Bluetooth—particularly Bluetooth Low Energy—devices, it is important to note that all of these features, some of which are deployed through firmware upgrades and others of which require new hardware, are optional. It will be up to the Bluetooth device manufacturer to decide which features to include in which products.
When the Bluetooth 4.1 standard was released last year, makers of Bluetooth integrated circuit controllers—the fundamental building block of Bluetooth devices—were shipping new chips compliant with that protocol within a month, says Kroeter, who expects some chipmakers will begin making products compliant with the 4.2 standard within a matter of weeks as well. The major suppliers of Bluetooth ICs include CSR, Broadcom, Texas Instruments, Nordic ID and Toshiba, but he does not yet have a list of chipmakers working to build products on the 4.2 standard.