In Bluetooth, various security and error correction mechanisms can be used: Authentication is used to ensure that a trusted relationship can be established. The size of the key used for the authentication algorithm is 128 bits.
An encryption mechanism protects the transferred data (payload). The key size may vary between 8 and 128 bits for the encryption algorithm. Frequency hopping (1600 hops per second), forward error correction (FEC), and cyclic redundancy checks (CRC) are used to ensuring that data will not be corrupted, even in crowded environments.
In addition, Bluetooth also allows for other application-specific security mechanisms to be developed and used.