The small files and delta blocks of data are first compressed and then encrypted with user-selected encryption method (e.g. 3-DES, AES 128, AES 256, etc.), which is set by the customer during the installation of the Backup Appliance. This key is unknown to Recovery Networks and the data remains encrypted at all times, even when stored offsite. The backup data is only unencrypted by the Backup Appliance at your site when it has retrieved the encrypted data from Recovery Networks Data Center for a restore.