Data collection using Key exchange provides 128-bit AES encryption for interview data collected by CAPI or ACASI. This option is turned under Interview Options, Security tab in the Design Studio. In the Warehouse Manager, the data manager will append their personal public key (based upon Windows login account information) to the control file to decrypt the interview data files.
Data files collected with key exchange encryption are initially saved with a .QED extension which is then renamed to a .QAD extension once decrypted in the Warehouse Manager.
Changing Windows Passwords
QDS password encryption is linked to your Windows account information. If you ever need to change your Windows password, this should be done by one of the following methods, depending on your Windows version/device type:
- Enter Ctrl+Alt+Del and then supply both the old and new passwords (desktop or laptop), or
- Go to the Settings App, Accounts, Sign In Options, Password (Windows 8/10 tablet)
If a Windows password is changed in a different manner (e.g. by a password reset), it may block access to any existing encryption containers and disallow you from installing the Read password.
Warning: Always have more than one user add their public key to the control file and always back up your Key Pair in case your Windows user profile is ever damaged or destroyed. If the Key Pairs are unavailable or lost, it will NOT be possible for the files to be decrypted by you or NOVA. Always keep a separate record of your Read password. If the password is lost, it will NOT be possible for the files to be decrypted by you or NOVA.
Note: Not applicable for data collected with the Web Module.