Composite DBMSs -tight integration
single image of entire database is available to any user
can be single or multiple sites
can be homogeneous or heterogeneous
Federated DBMSs - semiautonomous
DBMSs that can operate independently, but have decided to makesome parts of their local data shareable
can be single or multiple sites.
they need to be modified to enable them to exchange information
Multidatabase Systems - total isolation
individual systems are stand alone DBMSs, which know neither theexistence of other databases or how to communicate with them
no global control over the execution of individual DBMSs.
can be single or multiple sites
homogeneous or heterogeneous