mod_authn_dovecot is an authentication module for Apache that uses Dovecot as its authentication service, as Dovecot can have many authentication backends (MySQL, PostgreSQL, SQLite, PAM, and others).
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.