CTDA Technology

Fedora Commons

CTDA is built on the open source Fedora Commons architecture and uses a number of open source tools, applications, and services. Fedora (Flexible Extensible Digital Object Repository Architecture) was originally developed at Cornell University and the University of Virginia in the late 1990s. Fedora application development is currently managed by Duraspace, a non-profit organization dedicated to preserving scientific and cultural heritage digital assets. The Fedora repository architecture is currently in production in hundreds of academic, governmental, and cultural organizations around the world.


CTDA’s current management and presentation platform is Islandora. Islandora is an open-source software framework designed to help institutions and organizations and their audiences collaboratively manage and discover digital assets. Islandora was originally developed by the University of Prince Edward Island’s Robertson Library, but is now implemented and contributed to by an ever-growing international community. Islandora development is now managed by the Islandora Foundation, a non-profit membership organization.


CTDA implements the Handle System to provide persistent and unique identifiers for digital assets. The Handle System is a component of CNRI’s Digital Object Architecture and provides a means of managing digital information in a network environment. The Handle System includes an open set of protocols, a namespace, and a reference implementation of the protocols that enable a distributed computer system to store identifiers, known as handles, of arbitrary resources and resolve those handles into the information necessary to locate, access, contact, authenticate, or otherwise make use of the digital assets. This information can be changed as needed to reflect the current state of the identified digital asset without changing its identifier, thus allowing the name of the item to persist over changes of location and other related state information. All metadata is covered under the Creative Commons Zero License.

File Format Support

CTDA is committed to providing long-term access to all deposited content by applying best practices for digital preservation while also acknowledging the complexities involved in preserving digital information. CTDA will work within evolving “best practices” to be responsible stewards and will work to preserve the metadata and supported digital and media objects. CTDA will research the “state of the art” preservation practices and offer preservation ideas and recommendations. Choices regarding preservation will be based on CTDA’s community demand. Assessments will be continuously undertaken regarding ongoing technical feasibilities and digital repository “best practices.”

Any format can be deposited into CTDA. However, CTDA through Islandora provides services such as the creation of derivatives and technical metadata extraction for the following formats: doc, docx, ods, txt, html, sxc, csv, tsv, odp, sxi, ppt, pptx, xls, xlsx, warc, PDF, tiff/tif, jp2, jpg/jpeg, png, bmp, wav, mp3, ogg, mp4, mov, qt, m4v, and avi.

Technical Outline

Institutional affiliation and other indicators of viability of the project

Technical requirements, maintenance, and scalability




Administrative functions

Access and formats functions