Default Response to Get Alternate Representations

Note: This is draft content for the ELFIE ER. Please contribute and track discussion here

Non Information Resource Resolution and ELFIE

Non information resource identifiers, URIs that are an identifier for a thing that may or may not have information representations, are useful to provide persistent and reusable identifiers for entities such as real-world features. These non information resource identifiers provide a means for global identification across a system such that multiple members of the system can contain information about and/or in reference to shared entities. There is a basic conundrum with non information resource identifiers in that there can only be one default response when derefencing a URI and only one member of a distributed system can be the source of that default response. Further, in order to achieve linked system interoperability, dereferencing behavior of non information resource URIs needs to be in accord with the expectations of a member node of a system. The httpRange-14 and the Cool URIs Technical Report provide a significant basis for solving this conundrum and W3C working groups continue to focus on it, but many details remain to be agreed upon for use cases such as are being pursued by the ELFIE.

While details of the default dereferencing behavior of non information resource identifiers and subsequent redirects to information resources was discussed in the ELFIE, the IE has attempted to focus on encoding of linked data information resources rather than the network behavior for discovery and retrieval of non-information resources. Future work and best practice development will be needed to address these issues:

1. HTTP vs HTTPS
2. embedded hints and headers to canonical identifiers vs information resources
3. permanance and bookmarkability of information resource URLs
4. detecting information resource URLs and injecting canonical URIs into systems, so that other resources can be found
5. declaration of sameAs relationships
6. where sameAs relationships are mandatory and optional - where can an agent find these?
7. stricter definition of version vs schema vs content model vs profile