In order to use SSL-protected communications, such as exchanging Web traffic using the HTTPS protocol, an enterprise must first purchase and then install a digital certificate on its server. This involves selecting a certificate authority (such as Verisign or Thawte), proving your identity to that CA, paying a certificate fee and installing the certificate on the server. The exact technical steps will depend upon the type of server you're running, but each CA has detailed instructions on their websites for obtaining a certificate.
It's important that you obtain a digital certificate if you wish to provide users with the ability to securely connect to your website. Without a certificate, they will be unable to use SSL encryption to connect to your site and will not have a guarantee of your server's identity or the peace of mind that their information is encrypted while in transit over the Internet.
This was first published in December 2008