Only allow public/private key authentication ?

Hello,

I would like to know if there is a way to allow only public/private key
authentication, and so what is the exact signification of the
'PasswordAuthentication' configuration option.

I have disabled the PasswordAuthentication option but my sshd server
always asks me for a password and not a passphrase if I don't have the
good private key on my client.

Thanks if you can help,

C. Tobini

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