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Any number of mixins can be assigned to an object; they are cumulative.
Linked Data
Compliance with LDP 1.0 spec.
Node properties are RDF triples.
Metadata can be represented as RDF triples.
Search
Many possibilities for exposing, importing, sharing resources with other web applications.
Search
Fedora 4 includes an internal administrative search and the option to plug in external search applications...
Internal Search
...Simple property search and limited SPARQL endpoint.
External Search
Repository events generate JMS messages, which can be consumed by a JMS message consumer and relayed to an external search index (e.g. Solr).
Triplestore
Similar to external search, an external triplestore can be plugged into Fedora 4. The same JMS message consumer relays repository events to the triplestore index (e.g. Fuseki, Sesame).
Transactions
Multiple actions can be bundled together into a single repository event (transaction).
Transactions offer performance benefits by cutting down on the number of times data is written to the repository filesystem (which tends to be the slowest action)...
Clustering
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