SQL Anywhere Studio Security Guide
Keeping Your Data Secure
Encrypting a database
Controlling strong encryption
You can choose whether the encryption key is entered at the command prompt (the default) or into a prompt box. Choosing to enter the key in a prompt box provides an extra measure of security because the key is never visible in plain sight. Clients are required to specify the key each time they start the database. In cases where the database administrator starts the database, clients never need to have access to the key.
For more information, see -ep server option.