Characteristics

The XML Data Archiving Service has the following characteristics:

·        A hierarchy of collections used to organize archived data, called resources (also called XML DAS hierarchy).

·        Resources are addressed using URIs, which reflect where in the hierarchy the resources are located.

·        Searching for resources takes place either via the hierarchy or via a property index (value-based searches).

·        XML schemas are used to describe the structure of all XML resources within an archiving session; they are written to each collection together with their corresponding XML resources, and can be used for generating analyses of the archived data, for example.

·        XSL stylesheets are also written to the collection. They are used to, among other things, present the archived data in its original state later.

·        XML checks are performed to test for the well-formedness and validity (against an XML schema) of a resource.

·        A check sum can be used to check if a resource has been physically altered in any way; this could include a possible change in the data due to long-term storage.

·        Archive stores are used to flexibly map the XML DAS hierarchy onto storage systems. In other words, archiving objects write their data to separately assigned folders in file or WebDAV systems.

·        Resources can be packed: This entails the standard compression and bundling of resources in an openly documented long-term format.