What’s New In BT5.4 Bluetooth Specification?

1. Periodic Advertising with Response(PAwR)
PAwR is one of the key feature. Prior to Bluetooth 5.4, connectionless bidirectional communication is not possible. PAwR now allows bidirectional transfer of data in connectionless mode between a single central device and a large number of multiple devices (up to 32,640) in a star network topology.

2. Encrypted Adverting Data (EAD)
EAD provides a standardized approach to the secure broadcasting of data in advertising packets and enables the encrypted data over-the-star network to be decrypted only by devices that have shared the key material previously. This security feature protects PAwR communications to safeguard against data tampering, human error, and data leaks.

3. LE GATT Security Levels Characteristic(SLC)
When a GATT Client attempts to access a server attributes (characteristics, descriptors), attributes permissions are checked. If permissions are insufficient, the access is denied and all GATT features will not work properly. With SLC, the client can upgrade its security level to reattempt access of the previous failed operation. SLC enables devices to identify the security mode and level for all their GATT functionality.

4. Advertising Coding Selection
For LE Coded PHY, a Forward Error Correction (FEC) algorithm is used which results in significantly longer transmission distances. FEC parameter (S) uses one of two values (S=2 or S=8) and controls how much data is made to fix errors and how much Bluetooth range may be achieved. Prior to Bluetooth 5.4, specifying the value of the S coding parameter was not impossible. Bluetooth 5.4 allows the host to specify the value of the coding parameter S (S=2 or S=8) when the LE Coded PHY is selected for use with extended advertising.


Main beneficiary market of BT5.4
The combination of these features enables ultra-low power, efficient radio usage and secure star networks that can be deployed in large scale ESL (Electronic Shelf Labels) and sensor applications with transferring a small amount of data. Devices accept slightly longer advertising-delay to exchange an extended battery life. It’s easy to see the retail industry as well as the market for ESL and shelf sensors will benefit greatly. ESL are devices that display pricing information for product on retail store shelves. They use small electronic paper displays powered by batteries and can replace traditional paper labels. Besides, ESL use wireless technology and a central hub device to transmit data, allowing retailers to automate pricing and replace traditional manual processes, and creating more efficient in-store operations.