Even though the first Bluetooth-enabled mobile phone hit the market in 2000, the technology didn’t catch on until 2004 with the introduction of EDR (Enhanced Data Rate). Many improvements and revisions have been made to Bluetooth since then. A significant revision to Bluetooth that hit the market in 2010, Bluetooth 4.0 or Bluetooth Low Energy (LE), has had a massive impact on the IoT industry.
This blog will touch on the concepts of Bluetooth and BLE, map out the critical differences between the two, and briefly explain two types of communications for BLE.
What is Bluetooth?
Although Bluetooth has been popular since 2004, the advent of IoT-powered wearables like smart watches, wireless chargers, wireless headphones, etc. has added to its popularity. According to the official Bluetooth website, “Analysts anticipate that annual shipments of Bluetooth enabled devices will see 1.5x growth, a 9 percent compound annual growth rate (CAGR), from 2021 to 2026.”
Bluetooth is a short-range wireless technology which utilizes UHF (Ultra-High Frequency) radio waves having ISM bands from 2.40 GHz to 2.48 GHz.
Although it was initially built to provide an alternative for cables, it is now also used to build a Personal Area Network (PAN) for exchanging data between nearby devices.
What is Bluetooth Low Energy?
Bluetooth Low Energy (BLE) also called Bluetooth 4.0, is based on Bluetooth and was released in 2011. This Bluetooth technology focuses on low power consumption while offering many features similar to classic Bluetooth.
Due to an emphasis on low power consumption, it isn’t as fast as Bluetooth and hence, can’t be used to transfer large files. It is, however, an ideal solution for transferring small amounts of data with minimal consumption of power and without a need for large batteries. It is for this reason that a wide range of IoT devices such as sensors and tags use BLE.
How is BLE using Less Power compared to Bluetooth?
BLE and Bluetooth both use the same radio waves for exchanging the data. The key difference between both of them is that the BLE devices remain asleep between connections. In other words, BLE devices are designed to communicate only for a few seconds after they connect.
Hence, switching off between transmission enables BLE devices to communicate effectively.
On the other hand, classic Bluetooth was designed for continuous communication that can last for hours.
Difference between BLE and Bluetooth
Communication between BLE devices occur in 2 ways:
In connection-oriented communication, the BLE device acts as a central or peripheral device. This BLE device, which takes up the role of primary device, acts as the client and is responsible for searching other devices to which it can connect to. After finding the devices, it sends out the request for connection and data transmission.
A BLE device can also act as a peripheral device. In this case it would be receiving the request for pairing after being discovered in the radar by central device.
The entire communication takes 4 steps – Advertise, Initiate, Connect and Exchange.
Peripheral devices send out timed advertising packets. The central device scans for the advertising packets which it uses to find peripheral devices. The initiation stage is followed immediately after the advertising stage. Primary/Central device initiates a timed connection request, thus establishing a connection. The last step is the actual data transmission which occurs between the Central and Peripheral devices.
A broadcasting-based communication doesn’t require a connection to function; it simply broadcasts the raw data in an unidirectional format, which means that data would only leave from one end and can be received by any device around the broadcasting device which has sensing capabilities.
This method, however, doesn’t have any data security, as the transmitted data is accessible by anyone and we don’t have control over it.
Bluetooth Low Energy (BLE) or Bluetooth 4.0, is a version of classic Bluetooth that focuses on low energy consumption. It does this by switching off between transmission, thus leading it to require lesser and smaller batteries. This makes BLE the perfect choice for IoT-based applications and devices, despite being unable to transfer large files.