Protection of private information is essential for every wireless low energy device, from fitness bands to payment systems. Privacy mechanisms prevent devices from being tracked by untrusted devices.
Secure communications keep data safe while also preventing unauthorized devices from injecting data to trigger the system's unintended operation.
In Bluetooth Low Energy (BLE), devices connected to a link can pass sensitive data by setting up a secure encrypted connection, which means making the data unreadable to all but the Bluetooth master and slave devices.
A BLE connection is said to operate at a specific Security mode. Within each mode are several security levels. The required security mode/level of a connection may change from time to time, leading to procedures to increase that level.
To keep it simple, when two devices that initially do not have security wish to do something that requires security, the devices must pair first. This process could be triggered, for example, by a central device that is attempting to access a data value (a "characteristic") on a peripheral device that requires authenticated access.
Pairing involves authenticating the identity of two devices, encrypting the link using a Short-Term Key (STKs), and then distributing Long-Term Keys (LTKs) (for faster reconnection in the future, i.e., bonding) used for encryption.
The new security level of the connection is based on the method of pairing performed and this is selected based on the I/O capabilities of each device. The security level of any subsequent reconnections is based on the level achieved during the initial pairing.
Each device's role is defined in the Security Manager (SM) portion of the BLE stack. They are:
Security by means of encryption contains four levels
BleuIO has introduced a security feature into its latest release (firmware v2.1.1 ) which handles all four security levels to establish a secure BLE connection. Users can now use Numeric Comparison, Just Works or Passkey Entry to make data transmission more secure when working with Bluetooth low energy applications using BleuIO.
The table below is a reference for determining the pairing method based on the two devices I/O capabilities and each device's role in the process.
Source : https://microchipdeveloper.com/wireless:ble-gap-security
Use the following AT commands to make your BLE connection more secure.
AT Commands :
Share this post on :