For Identifiers (just the complete URI and local part, not about mechanisms)
| HDL | PURL | PURLz | HNRS | DOI | ||
---|---|---|---|---|---|---|---|
Yes ? | ? | ? | ? | ? | Yes | ||
Yes ? | ? | ? | ? | ? | Yes | ||
unique within our PID system without the DNS name portion of the | ? | ? | ? | ? | ? | Yes; very flexible naming, including pseudo/paths | |
? | ? | ? | ? | ? | Yes | ||
works with VIVO, arXiv, OAIS (CUL), Voyager Catalog, and WorldCat etc. | ? | ? | ? | ? | ? | Yes | does nothing in and of itself to not work with existing systems; |
Yes ? | ? | ? | ? | ? | Yes | ||
Yes ? | ? | ? | ? | ? | Yes | ||
Yes ? | ? | ? | ? | ? | Yes | ||
Yes ? | ? | ? | ? | ? | Yes | ||
completely flexible ? | ? | ? | ? | ? | Yes | ||
? | ? | ? | ? | Yes | Yes ? | ||
? | ? | ? | ? | Yes | Yes ? | ||
? | ? | ? | ? | ? | depends on the length | depends on the length and/or layout |
For Resolver and System
| HDL PURL | PURLz HNRS | DOI | ||||
---|---|---|---|---|---|---|---|
? | ? | ? | ? | ? | |||
? | ? | ? | ? | ? | |||
? | ? | ? | ? | ? | |||
Don't know; limited to the practical capacity of the underlying database. | Don't know – mention of 1996 tests resolving 50 resolutions/sec with a database of 500,000 PURLS in Long Introduction to PURLs | ||||||
Yes | Yes; PURLz is just a simple HTTP server using MySQL | ||||||
Yes | No - alpha stage | ||||||
Yes? | ? | ? | ? | ? | Yes | ||
? | ? | ? | ? | ? | Yes | Cloning an existing PURL and chaining a PURL | |
? | ? | ? | ? | ? | Yes; the resolvers can't be crawled without providing a dump | Yes; the resolvers can't be crawled without providing a dump | |
? | ? | ? | ? | Yes | Yes ? | ||
? | ? | ? | ? | ? | | not built in | |
Need to avoid unbounded generation of surrogate persistent identifiers | ? | ? | ? | ? | ? | ||
? | ? | ? | ? | ? | |||
? | ? | ? | ? | ? | |||
Depends on the Partial Redirect working – e.g., http://resolver.cornell.edu/netid/bdc34 |
Governance Issues
| HDL PURL | PURLz | HNRS | DOI | ||
---|---|---|---|---|---|---|
? | ? | ? | ? | one-time $50 payment per named resolver (not mirrors) | no ? | |
Can continue resolve IDs in absence of external organization | Yes? | ? | ? | ? | ? | Yes |
HDL is Corporation of National Research Initiatives's Handle system.
PURL is OCLC's PURL system.
PURLz is Zepheira's and OCLC's new persistent URL work.
HNRS is the Harvard Name Resolution Service.
DOI is IDF's DOI system
Footnotes
Uniqueness: We think PURLZ will reject the creation of a duplicate PURL, but we're not entirely sure how it deals with duplication when a PURL name component overlaps a PURL domain component – e.g., if we inadvertently created a domain /a/b/ with resource 1234 and someone later used the name b/1234 in domain /a/. Maybe pure string comparison for non-uniqueness is all that's required, but conventions need to be established to avoid confusion.Anchor unique unique