It’s rather discouraging that the server with foaf vocabulary seems to be down. Is it just me, or does everybody experience it?
I’ve seen various vocabularies down in the past. Sounds like a fundamental issue with linked data and interoperability. When a RDF document is down, we’ll survive. But when a vocabulary disappears, we lose that particular way of speaking about things.
Cool uris don’t change, but real ones change and disappear all the time.
No answer on the big question, but this is a handy resource if you know a prefix name and want to find its namespace(s) : https://prefix.cc. It lists dozens of alternate sites for FOAF, but unfortunately many of them are also unavailable.
Right, the applications using the term won’t stop just because the vocabulary disappeared.
Unfortunately a vocabulary like foaf also includes human-readable comments, and some guidance for terms’ usage (domain, range, disjointWith, deprecation notices…). Human developer loses a lot of value when a vocabulary disappears.
It’s unfortunate that the well meaning project that @jeffz mentioned seems to be (mostly) filled with defunct links and spam.
We seem to need redundancy. Relying on a single source of truth (behind the uri) has repeatedly proven not to work.
As long as we’re on the topic, allow me to gripe.: a) ontology links that break because of http/https b) what genius thought the prefix rdfs would help distinguish rdf-syntax from rdf-schema? c) skos has a CORS blocker on their ontology!.