Security Commands; Ky Command - Digi XBee User Manual

Commands
Parameter range
0 - 1
Parameter
0
1
Default
0
Bytes returned
1

Security commands

The following AT commands are security commands.

KY command

Sets the 256-bit Advanced Encryption Standard (AES) key for encrypting or decrypting data. Once set,
you cannot read the key cannot out of the device by any means. The firmware encrypts the entire
payload of the packet using the key and computes the CRC across the ciphertext. When you enable
encryption, each packet carries an additional 16 bytes to convey the random cipher-block chaining
(CBC) Initialization Vector (IV) to the receiver(s). Set 256-bit key (64 hex digits) on multiple devices for
encrypted RF communication. Set to 0 to disable encryption. Reading the parameter returns a 0
(encryption disabled) or 1 (enabled). The key cannot be read for security reasons.
A device with the wrong key (or no key) receives encrypted data, but the data driven out the serial
port is meaningless. Likewise, a device with a key receives unencrypted data sent from a device
without a key, but the output is meaningless. Because it uses CBC mode, repetitive data appears
differently in different transmissions due to the randomly-generated IV.
Note For international (non-U.S.) variants of XTC devices, the encryption key is 128-bit AES. The
command operates the same except the key length is 16 bytes rather than 32 bytes. This pertains to
part numbers ending with 128, no matter which firmware version is loaded. This also pertains to the
Australia version of firmware 22xx.
Binary command
0x43 (67d)
Command type
Security
Parameter range
0 - (64 hex digits all set to 'F')
Default
0 (disabled)
XBee®/XBee-PRO XTend Compatible (XTC) RF Module User Guide
Description
TX and RX
TX only
Security commands
60