The image url is: http://social.microsoft.com/Forums/getfile/57642/
I believe you are understanding the site collections and the sites from the above picture. [All site collections are using their own content databases]
SC6 is the main/big site collection in the diagram. It has 5 regions named Europe, Asia, East, West and Central. And there are "Department" sites in the same level as regions under the site collection.
The Department sites contains high level information which can be accessible by owners, managers etc. And each region also has department data which can be uploaded by the department users. Now, the requirement is all department owners able to see the department related data from a region directly in their department sites instead of going to the each region. And we have to write some custom logic to show the data from region sites in department sites.
Each region itself is very big and contains many sites in it.
And the questions are:
If we use the above architecture then the site collection (SC6) size will grow around 500-600GB in one year. But there are limitations on site collection size 100GB and Content database size 200GB. If we Remote Blob Storage then there are some other issues [But not sure]
We cannot create the region sites as site collections as the department users should be able to view the regions. [Implementation of permissions, security will be difficult]
So, how to resolve these kind of problems? Any suggestions will be greatly appreciated.