RF data encryption

[spoologa]

Hello,

The Gazell Pairing User Guide in the infocenter states that the AES ECB block is used for encryption & decryption. However, the product specification document for the NRF52840 specifially states that ECB block supports 128 bit encryption only and not decryption. 

How is the data received using Gazell decrypted? 

Also, what sort of error detection is used in this AES encyprtion? I'm not very familiar with AES, so I'm not sure how to properly ask this. Basically, we want 32bit CRC on all our data, but if the AES encryption and decryptions in itself has error checking, then we may not have to implement a CRC on top. 

Thanks,
SP

[Kenneth]

Hi,

Gazell pairing is using counter mode, as explained here:
https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Counter_.28CTR.29 

Notice it is using block cipher encryption both for encryption and decryption.

There is no error detection, so that must be added either as part of the encrypted packet or in addition.

Best regards,
Kenneth