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As noted above, as new namespaces are used for the first time, those namespaces will be bound permanently to particular prefixes. Currently, if the first use of a particular namespace should occur in RDF that is POSTed or PUT to the repository, regardless of any specific prefix binding supplied in the submitted graph, Fedora will instead bind the new namespace to a system-generated namespace in the form "ns00x". While this behavior is not incorrect, it is inconvenient, and not necessarily user friendly for human interaction with the repository. In order to avoid this behavior, the following best practices are recommended: (1) you can define a custom CND file which defines namespace prefixes; (2) use SPARQL update as the initial method of submitting a new namespace binding to the repository; and (3) "initializing" the repository with namespace bindings for the namespaces that are likely to be used, to prevent inadvertent POSTing or PUTting of new namespaces and the consequent exposure of opaque system-generated prefixesprefixes. Previously, it was possible to control the prefixes used by using SPARQL update or RDF with namespace prefixes, but this functionality does not currently work (see https://jira.duraspace.org/projects/FCREPO/issues/FCREPO-2376).
Defining a custom CND file
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