Bluetooth Low Energy protocol stack

The Bluetooth® 5.1 compliant Host and Controller implemented by the SoftDevice are fully qualified with multirole support (Central, Observer, Peripheral, and Broadcaster).

The SoftDevice allows applications to implement standard Bluetooth Low Energy profiles as well as proprietary use case implementations. The Application Programming Interface (API) is defined above the Generic Attribute Protocol (GATT), Generic Access Profile (GAP), and Logical Link Control and Adaptation Protocol (L2CAP). Other protocols, such as the Attribute Protocol (ATT), Security Manager (SM), and Link Layer (LL), are managed by the higher layers of the SoftDevice as shown in the following figure.

The nRF5 Software Development Kit (nRF5 SDK) complements the SoftDevice with Service and Profile implementations. Single-mode System on Chip (SoC) applications are enabled by the Bluetooth Low Energy protocol stack and nRF52 Series SoC.

Figure 1. SoftDevice stack architecture
SoftDevice stack architecture