When you log onto o your WordPress website, your credentials are checked against your database. Have you ever wanted to login using an external database? External Login is just the plugin for the job. It gives you the option to use an external database or a local WordPress one.
Thanks to this plugin, you can map the names of your database fields against WordPress fields as well as roles. Admins have the option to exclude certain users from accessing the admin areas based on fields in the external database. It supports MySQL, PostgreSQL, and Microsoft SQL databases.
External Login supports one salt for all passwords or separate salts for them. It also supports various hashing methods.