Bluetooth 5.3 is quickly becoming the standard for new devices. But do you actually need to upgrade your hardware to keep up with the latest Bluetooth standards?
A device's Bluetooth version determines its data transfer speed, power consumption and connection stability. With so many Bluetooth versions out there, though, it isn't easy to tell whether you're using the best one.
What Is Bluetooth 5.3?
Bluetooth 5.3 launched in 2021 and introduced several improvements for consumers and developers.
The biggest improvement in this version is connection subrating. Devices normally run on low-duty-cycle connections to save energy. But when high bandwidth is needed, the connection parameters change almost instantly, because otherwise there would be latency.
Connection subrating makes the switch between low-power and high-power modes faster, eliminating latency and giving users a better experience. For example, headphone audio that uses a subrated connection will have less latency than headphones without it, especially when the headphones are not close to the host device.
Bluetooth 5.3 also improves Bluetooth BR/EDR, the controller responsible for negotiating the encryption key size while a Bluetooth connection is being set up. This change lets the host device set the minimum acceptable key size, giving finer and more flexible control over encryption. It allows the host to decide what level of security it requires based on the sensitivity of the data being exchanged or compliance with security standards.
Two other notable features of the Bluetooth 5.3 update are channel classification and periodic advertising enhancements.
Channel classification lets peripheral Bluetooth devices communicate with the central device based on the peripherals' actual radio frequency conditions, which avoids interference and improves reliability.
The periodic advertising enhancement simplifies how devices share information. Bluetooth devices typically send the same data over and over to make sure it is delivered reliably. Now, devices using Bluetooth 5.3 can check for duplicates and skip unnecessary repeats, which saves energy and can extend the device's battery life.
The Bluetooth 5 Versions
| Bluetooth version | 5.0 | 5.1 | 5.2 | 5.3 |
|---|---|---|---|---|
| Release year | 2016 | 2019 | 2020 | 2021 |
| Data transfer | 2Mbps | No significant improvement | No significant improvement | No significant improvement |
| Communication range | 120 feet outdoors | Indoor positioning accuracy improved to 1cm. | No significant improvement | No significant improvement |
| New features | 255-byte message capacity | Enhanced Bluetooth LE audio | EATT for more efficient data transfer, the LC3 codec for better audio quality and CTKD for stronger security | Channel classification to reduce frequency interference and periodic advertising enhancements for better network efficiency |
Bluetooth 5.3 brings a range of new features, but let's look at how it differs from the earlier Bluetooth 5 versions.
Bluetooth 5.0
Bluetooth 5.0 arrived in 2016 and was a major improvement over Bluetooth 4.2. It has a message capacity of 255 bytes, 8 times the 31 bytes of Bluetooth 4.2. This doubled data transfer speed and quadrupled communication range while keeping power consumption low.
Data transfer speed also rose from 1Mbps to 2Mbps, range reached up to 120 feet indoors, and devices using Bluetooth 5 can stay on much longer than older devices.
Bluetooth 5.1
The Bluetooth 5.1 upgrade was released in January 2019. It makes it possible to locate connected devices over short distances and determine where a signal originates. Better location-based services improved indoor navigation and tracking.
Other updates include Generic Attribute Profile (GATT) caching, which changed how devices handle repeated data transfers, reduced power consumption, improved advertising and improved coexistence with other wireless technologies. Bluetooth Low Energy (LE) audio was also improved for better sound quality and synchronization.
Bluetooth 5.2
Bluetooth 5.2, released in early 2020, focused on improving audio quality.
Bluetooth Low Energy Power Control was introduced to optimize power consumption in low-energy devices. It also introduced the Low Complexity Communication Codec (LC3), which delivers higher audio quality and improves music playback and gaming. Together, these two components support Bluetooth Auracast, which allows audio to be broadcast simultaneously from a single device.
Bluetooth 5.2 also introduced the Enhanced Attribute Protocol (EATT). Previously, Bluetooth devices exchanged attribute data inefficiently to convey information about their status and capabilities. EATT streamlines this data exchange, making it more direct and resource-efficient and optimizing the communication channel.
Bluetooth 5.2 also introduced Cross-Transport Key Derivation, a protocol that simplifies encryption key management across multi-transport devices, thereby strengthening security.
What Is Bluetooth 5.4?
Bluetooth 5.4 is the latest version, officially released in early 2023. It includes several updates that improve Bluetooth functionality by enabling secure, two-way communication between low-power devices. These features include:
- Periodic Advertising with Responses (PAwR). Data is transmitted in small packets sent in subevents that an observer can synchronize with and respond to. This lets the observer scan for data only at specific times, which saves more energy.
- Encrypted advertising data. A standard method for encrypting advertising data, allowing some or all of the shared data to be encrypted. This means any Bluetooth-enabled device can receive advertising data from the host, but only devices with the decryption key (authorized devices) can access the encrypted data.
- LE GATT Security Levels Characteristic. It lets devices communicate the security levels required for access before trying to reach specific attributes. If a device does not meet the security level, the client prompts it to upgrade and gain access. This system prevents interruptions when switching applications, for a smoother and more secure experience.
- Advertising coding selection. It lets the host device decide which coding scheme to use when sending advertising data to the controller. This improvement gives more control over the trade-off between data speed and range, allowing performance to be optimized for specific communication needs.
All of these advances are especially useful in high-volume use cases, such as retail Electronic Shelf Label (ESL) applications, where countless devices are connected and synchronized, but they will also suit consumer tech products like headphones and earbuds.
