  We describe a digital object and respository architecture for storing and
disseminating digital library content. The key features of the architecture
are: (1) support for heterogeneous data types; (2) accommodation of new types
as they emerge; (3) aggregation of mixed, possibly distributed, data into
complex objects; (4) the ability to specify multiple content disseminations of
these objects; and (5) the ability to associate rights management schemes with
these disseminations. This architecture is being implemented in the context of
a broader research project to develop next-generation service modules for a
layered digital library architecture.
