PURLs are "persistent URLs". They may serve as a type of Identifier.

We use PURLs for two primary purposes:

  1. Advertising our content to people outside the DLP. These are always collection-level and item-level references. We make a commitment to maintain the PURLs in working order.
  2. Maintaining working references to files that are used by multiple machines/processes within the DLP. These can be references to individual files. Unfortunately, once a PURL is created, it is impossible to tell which machines/processes depend on it, so we must make some effort to maintain these in working order as well.

Creating PURLs:

Technical implications

Our current PURL resolver architecture has some technical implications that may unfortunately impact the collection identifier assignment for items.

MIME types

We haven't yet decided what to do with file types and MIME types. In most cases, we don't need to refer to a specific file type, but some applications may require this. Two options:

Sample PURLS


Page/image level:

Old format image level (may want to migrate):

Sample collectionID values

Main IU library collections:

IU archives:

Lilly library:

Other IU collections:

New Harmony Workingmens Institute:

Sample formatID values

See also