Thank you for your posting, garvinhicking & judebert

I think that I have found what I am looking for.
It should be useful for someone who finding it.

Just go to this website then try it.
http://drupal.org/

Why?
1. It's awesome and not too hard to install.
2. It's great to manage multiple public ...

Dear judebert,

Example:
- All users get 10MB after signup.
- We can specify a user to get 100MB for 1 month
- All users will not get remove

Sorry about my English.
Thank you for super fast reply

About "space size"
I mean that the storage size of all media files that 1 user can upload to the server. Such as 1 user can keep files on server only 10MB.

I want the plugin that able to

- specify the space size for public users
- specify the user expiration time

Yes, it's for multiple public users.
Please give me some advice~

Thank you so much!!!