Nextcloud is an open source cloud-based file storage and sharing platform that can be installed on-premises or hosted in the cloud. Nextcloud includes features such as file versioning, file sharing, and file encryption, and can be used for sharing very large files securely and efficiently. Nextcloud utilizes a web server (like Apache or Nginx) and a database (such as MySQL/MariaDB or PostgreSQL) to store and manage files. The file transfer is done via HTTP(S), with support for chunked uploads which allows large files to be split into smaller parts to handle them more efficiently. Nextcloud also has a built-in WebDAV server for more advanced use cases.