+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ PasswordAuthentication Specifies whether password authentication is allowed. The de- fault is ``yes''. Note that this option applies to both protocol versions 1 and 2. PermitEmptyPasswords When password authentication is allowed, it specifies whether the server allows login to accounts with empty password strings. The default is ``no''. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ If PasswordAuthentication is yes, then you'll need to ensure that PermitEmptyPasswords is also yes, or you won't be allowed passphraseless authentication. If you're not permitted to change that, just use a simple ssh passphrase.