Encrypt/Decrypt some fields.
Encryption and Decryption are based on a symmetric key (i.e. there is one unique key that allow encryption and decryption). The key is save inside a “Key File”. You need a “Key File” to encrypt or decrypt your data.
To select a “Key File” (using the “Browse” button) or to create a new “Key File” (using the “Create New Key File” button), you need to switch to “Expert-user-mode”. To switch to expert-user-mode: Click the button in the main toolbar of the application! Once you are in “expert-user-mode”, the “Browse” button and the “Create New Key” button are enabled.
When you click the “Create New Key” button, Anatella opens this Window:
By moving randomly your mouse inside this window, you generate random numbers that are used to create a 100% random key. This encryption key is saved inside a “Key File” or inside a string (this last option allows to use a “Global Parameter” to specify the key when decrypting the data).
The encryption algorithm used inside Anatella is symmetric. This guarantees that there will never be any “collisions”. For example: Let’s assume that you are encrypting many MSISDN (i.e. many phone numbers): because there are no collisions, the number of distinct MSISDN before and after encryption is the same. There will never be 2 different un-encrypted MSISDN that are “mapped” to the same encrypted MSISDN (i.e. there are no collisions, never).
Since there are no collisions, you can safely use the encrypt Action to anonymize your datasets. In particular, when anonymizing datasets containing MSISDN numbers, you’ll lose, after encryption, some precious information about the MSISDN. The lost information is:
•Is it a “short” phone number? (e.g. like the voice-mail number)
•Is it an international call?
These pieces of information are *very* important when analyzing communication-graphs using SNA (Social Network Analysis) algorithms. You can use:
•The “Extract Original Prefixes” option to keep un-encrypted the first few digits of the MSISDN (This allows to detect international calls).
•The “Extract Original Lengths” option to save the length of the un-encrypted MSISDN (This allows to detect “short” phone number like the voice-mail number).