In order to use public key authentication with Dropshare for Mac and SCP over SSH upload, an SSH key pair is required. Follow these steps in case you don't know how to create a key pair.
Terminal.app is located at /Applications/Utilities/Terminal.app.
Generate new SSH key pair
Follow the explainations to generate a new SSH key pair.
$ ssh-keygen -t rsa Generating public/private rsa key pair. Enter file in which to save the key (/Users/username/.ssh/id_rsa): [Enter "id_dropshare" e.g.] Enter passphrase (empty for no passphrase): [Enter your passphrase] Enter same passphrase again: [Enter your passphrase again] Your identification has been saved in /Users/username/.ssh/id_dropshare. Your public key has been saved in /Users/username/.ssh/id_dropshare.pub.
Upload SSH key pair to server
The following command will upload your public key generated above to the server.
$ cat id_dropshare.pub | ssh [Your server's hostname] 'cat >> ~/.ssh/authorized_keys'
Set up the key pair in Dropshare for Mac
Open the Dropshare for Mac preferences window, navigate to the Connection tab, switch to appropriate connection, select both your generated private and public key, and enter your passphrase in the password field. You are now able to upload files using SCP over SSH and public key authentication.