Mediamosa is an open source video backend built with Drupal. It uses a RESTful API and XML to allow video files to be uploaded, stored, transcoded and streamed through a scalable service-oriented architecture. Key features include access control lists, transcoding with FFmpeg, and support for open standards. Mediamosa provides a media asset management system and can scale to dedicated servers for upload, processing, streaming and thumbnails. It includes Drupal modules to integrate video playback and management into Drupal sites.