On each database server that hosts a QMF catalog, the main QMF catalog is called <Default>. All QMF for Windows objects and user objects for this database server are stored in the <default> catalog.
You can specify that the database server that you are configuring in the SDF use the default QMF catalog that resides on the same database server or a QMF catalog that resides on a different database server. All user objects from a database server that is sharing a QMF catalog on another database server are also, by default, stored in the main QMF catalog.