web file server framework with permissions?

I work for a company where we do a lot of digital projects and need back and forth uploading/downloading of assets and files between clients and employees. Ideally I want to put in place a web portal where users can login and access a designated are开发者_StackOverflowa to upload/download files. Must be isolated from other users/clients and secure so I was thinking of creating an admin panel to set permissions to a user database.

This sounds like a common need to me. Are there any free or open frameworks that do this?

If I end up building this custom, using html, js, mysql, php, what would be the ideal backend setup for storing files? i.e. what type of server configuration would be secure and robust? Thanks

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ResourceSpace—free and open source digital asset management. The documentation's good and covers most situations, including configuring it to separate clients. The permissions configuration is a bit cryptic, but maybe they've improved that since I installed/updated it last (a while back). And it has a "pluggable remote API architecture."

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Widen provides digital asset management software in a fully hosted environment. Digital asset management is becoming very popular with every type of business for easy retrieval and safe storage all their media files.