DB Backend
Db Backend is interface whitch is used for connection with database. We write in database type of multimedial data (using MIME types), name of file and/or description and location of data (in URL format). If data is stored on local disc, then URL looks like file://folder path/file name.
Apart this data in database is stored a list of all awalible agents, and data types that is posible to reproduce on every particular agent. To database accede purely DB backend, and to the database accede purely "Matica" on clients or agents request.
