Community Server supports username/password and OpenID options for logging in to your Web site. OpenID is a shared identity service which allows users to log on to multiple Web sites using a single identity, and removes the need for a user to remember a username and password when they logon to your Web site.
However, you can disable OpenID option so all users must log in with a username and password specific to your Web site. To disable the OpenID option so it is invisible on the login page, move the CommunityServer.OpenId.dll and Janrain.OpenId.dll files from the /bin/ directory of your Community Server site to another folder on your server. If you want to enable OpenID later, you can move the files back to the /bin/ directory.