Client certificate selection

I have a https apache 开发者_如何转开发server that needs client verification. But when somebody is browsing this site there is need to select proper cert from list of certificates installed in browsers. What can I do to become client cert default to my webpage (so clients do no need to select cert)

Is your certificate valid and signed by a 3rd party root authority like Thawte, Verisign... etc?

You can't control from the server which client certificate is presented - you can only indicate that you expect a clientside certificate (SSLVerifyClient). Most browsers allow the user to associate websites with individual client certs. There is no way to manipulate this from the serverside.