There are two ways to setup passwordless logins to a remote server and RsyncOSX supports both. It is advised to use ssh and ssh-keys, method one below, because the traffic is encrypted and it is considered more secure.

Encrypted protocol by ssh and ssh-keys

Utilizing ssh enables passwordless logins to remote servers by ssh private and public key-pair.

Using ssh-keys is in general considered more safe than standard password solutions (single factor authentication). ssh-keys is based upon public-key cryptography.

Rsync transfer data between client and server by tunneling transfer of data in an encrypted ssh tunnel.

Not encrypted protocol by rsync daemon

There is also possible to setup RsyncOSX utilizing a rsync daemon setup for synchronizing files to remote servers.

  • this is a special setup and require some tweaking

Rsync is reading a local file with password information when connecting to the server side rsync daemon. The transfer of data between client and server is not encrypted.