Sign FOAF Document, Add Trust to Web

Thinking about FOAF and Thunderbird integration, for it all to work, FOAF documents should be signed (PGP/GPG for instance). A nice little trust web would emerge. Signing a FOAF document (or, more accurately, a set of triples) would mean "I verify that these triples are correct to the best of my knowledge" Same principles would apply from signing others' PGP keys (from a trust perspective).

So, in an effort to see if we can sign RDF triples, I stumbled upon the
Tech Report: HPL-2003-142: Signing RDF Graphs. The Jena guys do it again!

From the article synopsis:


However, it is possible to define a large class of canonicalizable RDF graphs, such that digital signatures for graphs in this class can be created and verified in O (n log (n)). Without changing its meaning, an arbitrary RDF graph can be nondeterministically pre-canonicalized into a graph of this class, before signing. The techniques in this paper are key enablers for the use of digital signature technology in the Semantic Web.

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