A method for updating a group encryption key association, the method includes receiving an encrypted group key from a second device, where the group key has been encrypted using a device key of a first device. The method further includes, in the first device, using the group key to encrypt an input vector, transmitting the encrypted input vector, encrypting privacy-sensitive information using a device key, an encryption algorithm, and the input vector, and transmitting the encrypted privacy-sensitive information to the second device.