Access Role
A named role, such as "writer", that is assigned to a user, group or some other identifying principal within part of the repository. Roles may be used by the policy enforcement point (PEP) to authorize actions taken in the repository.
Binary
A binary in a Fedora repository is a nonRdfSource resource. In other contexts, binaries would sometimes be described as bit-streams or files. Binaries are always accompanied by a nonRdfSourceDescription.
Checksum
A computed fingerprint for binary content, used to ensure a complete transfer or the fixity of stored information. Fedora supports the SHA-1 checksum algorithm for safely uploading content.
Children
The resources which are immediate children of a given container. Properties are not counted as children.
Compact Node Definition (CND)
A file format defined by JCR here that allows for the definition of new resource types and namespaces. It is highly recommended that users do not modify Fedora 4's CND file, as such modifications may limit the ability for subsequent Fedora version upgrades of the repository installation.
Container (formerly known as: object)
A container is a resource that is the primary organizational entity in a Fedora repository. Containers may container other containers or binaries and their nonRdfSourceDescriptions.
Federation (aka Projection)
The process by which a repository may present objects through the API that are actually stored in a different system, such as a file system or database.
Fixity
Fixity is the integrity of stored information over time. Fedora performs fixity checks on demand by comparing a stored checksum with one that is newly computed.
Indexer
Creating, modifying or deleting objects in the repository generates events. The indexer monitors and processes these events; by ingesting relevant RDF to an external triplestore, for example.
Inlined Resources
Includes the current node's parent node, and any child nodes it may have. Child datastream nodes also show their content node (jcr:content).
jcr/xml
An XML document which has a format that represents JCR resources. It can be used to import a set of nodes and properties into a workspace. Or it can be used to export a full representation of a Node. See https://docs.jboss.org/author/display/MODE/Initial+Content for more detail.
Linked Data Platform (LDP)
The W3C Linked Data Platform (LDP) specification describes a set of best practices and simple approach for a read-write Linked Data architecture, based on HTTP access to web resources that describe their state using the RDF data model. Fedora 4 implements the LDP specification for create, read, update and delete (CRUD), allowing HTTP, REST, and linked data clients to make requests to Fedora 4.
Managed External Datastreams
Refers to content that is managed by Fedora as a federated/projected datastore, as an object that sits outside the Fedora-configured objectStore but can have audits, versioning, checksums, etc. handled by Fedora.
Namespace
A namespace is a container for a set of identifiers (also known as symbols, names). In Fedora 4, resource properties may belong to any namespace providing semantic assertions that support interoperable metadata. Namespaces are restricted to being an empty string or to a URI as defined in section 3 of RFC3986. An example of a namespace would be "http://purl.org/dc/elements/1.1/".
NonRdfSourceDescription (formerly known as: datastream)
A nonRdfSourceDescription is a resource that describes a binary resource within the Fedora repository. A nonRdfSourceDescription is always accompanied by a binary, and vice versa.
Object (aka Fedora Object)
A node type with the Primary type of [nt:folder] and a Mixin type of [fedora:object]. It is the primary organizational node in a Fedora repository.
Policy Enforcement Point (aka PEP)
This is a pluggable component in the Fedora framework that is responsible for authorizing all actions take on objects.
Prefix
Typically a short string representation of an associated namespace. For example the prefix "dc" could be used to represent the namespace. "http://purl.org/dc/elements/1.1/". If we wanted to access an element (e.g. "contributor") within that namespace we could do it with the prefix "dc:contributor" or in the full form "http://purl.org/dc/elements/1.1/contributor".
Prefixes are limited to the following grammar:
LocalName ::= ValidString - SelfOrParent
/* Any ValidString except SelfOrParent */
SelfOrParent ::= '.' | '..'
ValidString ::= ValidChar {ValidChar}
ValidChar ::= XmlChar - InvalidChar
/* Any XmlChar except InvalidChar */
InvalidChar ::= '/' | ':' | '[' | ']' | '|' | '*'
XmlChar ::= /* Any character that matches the Char production at http://www.w3.org/TR/xml/#NT-Char */
Properties
Properties are name/value pairs that belong to resources. The name of a property can be any term from a namespaced vocabulary. When RDF is generated in response to a request for a resource that contains properties, the RDF will contain triples for each property where the subject of the triple is the resource itself, the predicate of the triple is the property name, and the object of the triple is the value of the property. Property values can be of any valid rdf:type.
rdf:type
An RDF property that is used to define that the Node described belongs to a class of functionality / behavior. For example http://www.w3.org/ns/ldp#Container is an rdf:type that denotes the node can contain other nodes. The official definition can be found here.
Repository
A repository is a single, self-contained persistent store of information plus the software that is used to access and update that information. Fedora is a repository.
Resource
Resources are the primary organizational structure in the repository. A resource is any web-addressable entity, such as a container, a nonRdfSourceDescription, or a binary. Every resource has a name and a unique identifier, and can also be identified by a path. They are comprised of zero or more properties / child resources.
Transactions
A transaction represents a series of changes to the repository that must execute successfully and completely or not at all. Transactions should be used to ensure consistency. Each transaction succeeds or fails as a complete unit; it cannot remain in an intermediate state.
Triple
Uniform resource identifier (URI)
A string of characters used to identify a name of a web resource. It is defined in RFC3986, section 3. An example of a URI would be "http://purl.org/dc/elements/1.1/".
Universally Unique Identifier (UUID)
A "practically" unique identifier that is used to identify a node.
Version
A snapshot of a resource that is saved in version history for later access.
