CloudSync supports encryption of file libraries to strengthen your data security. To encrypt a file library, you need to set a password when you create a library.
The password won't be stored on CloudSync cloud platform. So even the administrator of the servers cannot view your encrypted data without the password.
To download and sync an encrypted library to your computer, you need to provide the password. CloudSync client program will download the encrypted data and decrypt it on your computer.
To share an encrypted library with your friends, you also need to tell them the password.