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Cross-Domain-Interoperability-Framework / Discovery

Repository for work on CDIF Discoverability workstream
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cardinality of 'checksum' #4

Open smrgeoinfo opened 1 year ago

smrgeoinfo commented 1 year ago

Pascal Heus 7:24 AM Jun 27, from Google doc We can have more than one checksum. Would make this repeatable.

smrgeoinfo commented 1 year ago

This would only make sense to me if the multiple values were for checksums calculated with different algorithms. A checksum fingerprints a digital object. In the current design, the metadata record can be about a single digital object, or about a resource that has multiple representations (distributions), each of which is a distinct digital object. In the second case there could be multiple checksums in the metadata record, but each is scoped to a different distribution. Different checksum == different digital object.

hvdsomp commented 11 months ago

In ResourceSync, one hash is allowed. It is provided in the hash attribute of the not repeatable rs:md child element of the sitemap url element. The hash value is preceded by a token that indicates the algorithm that was used to compute the hash. An example would be:

<rs:md hash="md5:1e0d5cb8ef6ba40c99b14c0237be735e" />

See http://www.openarchives.org/rs/1.1/resourcesync#DocumentFormats