The Content Object Repository Discovery and Registration/Resolution Architecture (CORDRA) is an open, standards-based model designed to support an interoperable federation of independent content repositories. It prescribes design and implements software systems to enable content discovery, sharing, and reuse. This effort is currently being developed within the ADL Initiative as a process for registering repositories maintaining assets using the Handle System of Uniform Resource Identifiers (URIs). The CORDRA architecture is being developed by the Advanced Distributed Learning (ADL) Initiative, Corporation for National Research Initiatives (CNRI) and the Carnegie Mellon Learning Systems Architecture Lab (LSAL). CORDRA is content-agnostic and applies to all domains.

The ADL Registry is the first instance of the CORDRA model and is designed to serve the needs of the DoD community. Other instances are expected to emerge to support other communities of practice.

CORDRA is an enabling model bridging the worlds of content management and delivery, and content repositories and digital libraries. CORDRA aims to identify and specify (not develop) appropriate technologies and existing interoperability standards that can be combined into a reference model used to enable a learning content infrastructure.

CORDRA is:

• A formal model that can be used to design federations of repositories (the CORDRA reference model)
• A collection of operational systems built from the CORDRA model, including:
  • A prototype implementation of a repository federation
  • An operational federation of federations used to combine different CORDRA federations

CORDRA is not:

• A repository of content. It is a searchable index of content metadata that can be resolved to content located in distributed repositories.
• CORDRA does not define or dictate how a repository operates, nor does it affect local policies. It only defines how to make deposits in the registry.

ADL-R is an important step in unifying DoD learning, knowledge and performance content, and is the first implementation of CORDRA.

Instances of the CORDRA model will be made available as open source software (OSS) through a General Public License (GPL), making CORDRA available to other communities of practice outside of DoD. Other CORDRA 'instances' (registries) are expected, and each of these instances can be connected - by design - through a "registry of registries" and thereby provide an authoritative means to discover learning content on a global basis.