The XDB Server uses a logical storage architecture modeled after the architecture used by IBM's DB2. This architecture allows you to use the same three-part naming conventions (location-name.authid.object-name) typically used on the mainframe.Because much of the physical storage architecture employed on the mainframe has no equivalent in PC environments, the physical storage between the environments differs significantly. However, the physical implementation of the XDB Server generally makes these differences transparent to the user.The XDB Server allows you to explicitly define where data is to be stored or to use the system-generated defaults. With either method, data is accessed by using the logical names of objects, not by referencing the physical storage locations. The XDB Server performs the mapping between physical and logical layers automatically.