Understanding BLE essentials for devices and smartphone communication

Bluetooth Low Energy (BLE) (also known as Bluetooth Smart or Version 4.0+ of the Bluetooth specification) consumes less power and it is app-friendly version of Bluetooth that is built for the Internet of Things (IoT).

The power-efficiency of BLE makes it opt choice for devices that needs to run for long period on power sources such as small sized batteries. The great thing about BLE is the native support for Bluetooth technology on every major operating system, for easy mobile application development, connectivity for cloud computing and the social economy.

What it means for your customers

BLE powers the Internet of Things. You wake up and perform your daily exercises with a heart rate monitor that communicates with your mobile phone or smartwatch, then listen to music using wireless speakers. You unlock your doors, set the temperature up or down, turn on or off the lights and control your gadgets using the smartphone or tablet you already own. All these wirelessly connected devices make your life comfortable and make you more productive.

Developing with Bluetooth low energy

For Developers and OEMs it requires very minimal learning curve when it comes to mastering BLE so they can create great new products that communicate with the billions of Bluetooth enabled devices already in the market. BLE is cheap and developer-friendly, that offers flexible development architecture so even sky is not the limit.

Key features of BLE include:

• Multi-vendor interoperability as it uses industry-standard wireless protocol.
• Because of low power consumption its battery lasts up to 2-3 years.
• Efficient app development architecture with low cost and fast turn around time.
• Can work with best security standards like 128-bit AES data encryption.

Market advantages

Penetrate the market with ever increasing Bluetooth device ecosystem with billions of devices worldwide.

• Innovate, iterate and make money faster with BLE solutions.
• BLE will help you design and device new level of customer loyalty programs and provide great analytics into customer behaviour.

How BLE is different from Classic Bluetooth?

BLE is different compared to classic Bluetooth when it comes to how radio signals are transmitted, data transfer rates, profiles available and speed of initial connection.

Standard BLE Architecture

With BLE, data transfer involves server (device with sensor) and a client (consumer of data). Smartphone can act as both client and server. In BLE terms server is known as Peripheral and client is known as Central. 

BLE Protocol Stack is divided into two sections : Controller and Host. BLE is a star topology network. BLE devices has following states : Standby, Advertiser, Scanner, Initiator, Master and Slave. Most important aspect for data transfer is the advertisement packet and how the data is organized.  

GAP (Generic Access Profile):

GAP defines generic procedures for connection related services like Device Discovery, Link Establishment, Link Management, Link Termination and initiation of security features. GAP profile roles are broadcaster (you can’t connect with it), observer (it can scan for advertisement but can’t initiate connection), Peripheral (it is an advertiser that is connectable), Central (it can scan for advertisement and can initiate connections).

GATT (Generic Attribute Profile):

This profile consists of one or more ‘services’ necessary to satisfy a use-case. Service contains attributes known as ‘characteristic’ values which will have ‘characteristic declaration’ attribute right before the value. Characteristics may have optional ‘descriptor’ attributes.

ATT (Attribute Protocol):

ATT defines over-the-air (OTA) for reading, writing and discovering attributes. An attribute is a value that has following : A handle (Address), a type and set of permissions

L2CAP (Logical Link Control and Adaptation Protocol):

L2CAP permits upper level protocols and apps to transmit and receive upper layer data packets up to 23 bytes in length. It provides channel management allowing for logical channels between two endpoints.

Core Bluetooth Framework(iOS/Mac)

The Core Bluetooth framework provides the classes needed for iOS and Mac apps to communicate with devices that are equipped with BLE wireless technology. For example, your app can discover, explore, and interact with low energy peripheral devices, such as heart rate monitors and digital thermostats. As of OS X v10.9 and iOS 6, Mac and iOS devices can also function as BLE peripherals, serving data to other devices, including other Mac and iOS devices.

Android & BLE

Android provides following classes as part of bluetooth: Bluetooth xxxxx (Adapter, Device, Gatt, GattCallback, GattCharacterisitc, GattService, Manager, Profile), Bluetooth.le.xxxxx (ScanCallback, ScanFilter, ScanResult, ScanSettings).

LetsNurture has provided numerous solutions for BLE devices like Heart Rate Monitor, Temperature Sensors, Beacons. Please contact us if you are looking for any BLE related Internet of Things solutions.