This sounds like the perfect plugin for me to have to set up a site for just family members to easily jump on without the hassle of authenticating via username and password.
However just need some advice on how to start utilising the plugin correctly, here are the next steps I would envision I would need to perform:-
1) Create a Certificate Authority & Server SSL certificate as standard
2) Create client certificates on devices for each user; this time cn is anything but email address details has to match a user's email address on wordpress user list? Correct me if I am wrong?
3) Then enable apache for SSL client certificate authentication
Sorry for being thick, but any help would be most appreciated.