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Update 2005-05: On May 01, 2005 OASIS announced that the OASIS ebXML Registry Information Model (RIM) v3.0 and ebXML Registry Services and Protocols (RS) v3.0
specifications had been approved as OASIS Standards, following public review and submission of the specifications for ballot by the OASIS membership. In addition to the two principal prose specifications in PDF (ebXML Registry Information Model 3.0, ebXML Registry Services and Protocols 3.0), the ballot submission package contains five XML Schemas (xsd), twenty-one XML scheme files, and ten WSDL description files.
[February 14, 2005] The OASIS ebXML Registry Technical Committee has voted to approve its ebXML Registry Version 3.0 specification as a Committee Draft and to advance the draft for public review in preparation for ballot as an OASIS Standard.
The ebXML Registry Version 3.0 release is a package of some forty-four files, including the two prose documents ebXML Registry Information Model (RIM) and ebXML Registry Services and Protocols (RS). XML schemas and WSDL files complete the distribution. The specification uses schema documents conforming to W3C XML Schema, and normative text to describe the syntax and semantics of XML-encoded objects and protocol messages.
An ebXML Registry is "an information system that securely manages any content type and the standardized metadata that describes it. It provides a set of services that enable sharing of content and metadata between organizational entities in a federated environment. An ebXML Registry may be deployed within an application server, a web server or some other service container. The registry may be available to clients as a public, semi-public or private web site. The ebXML Registry thus provides a stable store where submitted information is made persistent. Such information is used to facilitate business to business relationships and transactions."
In this context, submitted content for an ebXML Registry includes, but is not limited to: XML schema and documents, process descriptions, ebXML Core Components, context descriptions, UML models, information about organizations, and software components.
The ebXML Registry Information Model (RIM) specification defines the types of metadata and content that can be stored in an ebXML Registry. The companion document ebXML Registry Services and Protocols (RS) defines the services provided by an ebXML Registry and the protocols used by clients of the registry to interact with these services.
According to the RIM specification, an ebXML Registry is capable of storing any type of electronic content such as XML documents, text documents, images, sound and video. Instances of such content are referred to as a RepositorytItems. RepositorytItems are stored in a content repository provided by the ebXML Registry. In addition to the RepositoryItems, an ebXML Registry is also capable of storing standardized metadata that may be used to further describe RepositoryItems. Instances of such metadata are referred to as a RegistryObjects, or one of its sub-types. RegistryObjects are stored in the registry provided by the ebXML Registry."
The ebXML Registry Version 3.0 specification outlines a number of registry use cases. "Once deployed, the ebXML Registry provides generic content and metadata management services and as such supports an open-ended and broad set of use cases. The following are some common use cases that are being addressed by ebXML Registry: (1) Web Services Registry, used for publishing, governance, discovery and reuse of web service discriptions in WSDL, ebXML CPPA and other forms; (2) Controlled Vocabulary Registry, which enables publising, governance, discovery and reuse of controlled vocabularies including taxonomies, code lists, ebXML Core Components, XML Schema and UBL schema; (3) Business Process Registry, which enables publishing, governance, discovery and reuse of Business Process specifications such as ebXML BPSS, BPEL and other forms; (4) Electronic Medical Records Repository; (5) Geological Information System (GIS) Repository that stores GIS data from sensors."
Version 3.0 of the ebXML Registry adds considerable functionality vis-à-vis version 2.0. The version 2.0 specifications for RIM and RS were approved as OASIS Standards in May 2002. According to a summary provided by specification co-editor Farrukh Najmi, a key focus of V3.0 "is federated and secure information management capabilities. A new federation feature enables multiple registries to seamlessly provide a unified information store that enables clients to discover any information using a single federated query that searches all members of the federation. Information in one registry can seamlessly link with information in any other registry and any information from one registry may be replicated in any other registry."
A royalty-free, open source implementation of the latest TC Approved ebXML Registry 3.0 specifications is available from the freebXML Registry project.
Upon request, Farrukh Najmi (Sun Microsystems) has provided a description of new functionality in the ebXML Registry Version 3.0. Together with Sally Fuger and Nikola Stojanovic, Farrukh is co-editor of the ebXML Registry Information Model Version 3.0 (RIM) and ebXML Registry Services and Protocols Version 3.0 (RS) specifications:
[Farrukh writes:] An ebXML Registry is a federated registry and repository that manages
all types of electronic content described by standard and extensible
meta data. To use a familiar metaphor, an ebXML Registry is like your
local library. Its repository contains all types of electronic content
much like the library contains all types of printed content. Its
registry contains meta data describing the content much like the
library's card catalog contains information about its printed content.
Any number of ebXML Registries can work together to offer a unified
service much like multiple libraries can participate in a cooperative
network and offer a unified service.
The central theme of version 3.0 is federated and secure
information management capabilities. A new federation feature enables
multiple registries to seamlessly provide a unified information store
that enables clients to discover any information using a single
federated query that searches all members of the federation. Information
in one registry can seamlessly link with information in any other
registry and any information from one registry may be replicated in any
other registry.
Since the federation capability blurs the boundaries between registries,
it demands enterprise security features such as as federated identity
management, federated policy management, authentication, access control
and authorization both within and across enterprise boundaries.
To meet these increased demands for security in a federated environment
version 3.0 leverages the OASIS SAML 2.0 specifications to enable
federated Identity Management, Authentication and Single Sign On (SSO)
across federation members. Version 3.0 also leverages the OASIS XACML
1.0 standard to enable fine grained access control expressed in XACML
Access Control Policies. In addition version 3.0 leverages OASIS WSS:
SOAP Message Security 1.0 and OASIS WSS: SOAP Message with Attachments
(SwA) Profile 1.0 to secure the registry's SOAP protocol messages using
digital certificates.
Another major theme of ebXML Registry version 3.0 are
content management capabilities. Version 3.0 defines an extensible
service interface and protocol for adding Content Management Services
(CMS) as plugins to an ebXML Registry. It also defines two specific CMS
interfaces, a Content Validation Service interface and a Content
Cataloging Service interface. Content Validation Services automatically
enforce domain specific business rules when content is published to the
registry, consequently improving the quality of content in a registry.
For example, in the medical domain a Content Validation Service plugin
could automatically enforce the business rule that a Medication Order
does not conflict with an allergy recorded for the patient. The registry
does not accept any content that is deemed invalid by a relevant Content
Validation Service. Content Cataloging Services automatically catalog
published content based upon domain specific rules.
For example, an image published to the
registry could automatically by classified as monochrome, gray-scale or
color and enable queries that can search specifically for color images.
Content Cataloging feature makes registry content more discoverable.
A new content versioning feature enables any content or meta data in the
registry to be automatically versioned whenever it is updated. The
feature is based upon the IETF RFC 3253 also known as Delta V.
Version 3.0 defines a new HTTP binding to the ebXML Registry service interfaces using a REST
style architecture. The HTTP binding enables any content or meta data in
the registry to be accessible over an HTTP URL using a standard web
browser. The registry assigns a default URL to all content and meta data
which may be augmented with publisher defined URLs. The HTTP binding
also supports a file/folder metaphor that enables content in the
registry to be organized in folders much like a file system. The HTTP
binding enables registry folders containing content and meta data to be
browsable using a standard web browser. The HTTP binding complements
the existing SOAP binding to the ebXML Registry.
Since its inception the ebXML Registry has supported arbitrary ad hoc
queries using either a standard SQL-92 syntax or an XML Filter query
syntax. While this feature enables flexible discovery use cases, the
resulting queries can be complex and daunting. To address this concern
version 3.0 adds a Parameterized Stored Query feature that allows a
query to be stored in the registry in parameterized form. To invoke the
query a client simply provides some or all of the query parameters, and
is blissfully spared the underlying complexity of the query. Typically
such parameterized queries are exposed to the user as Web Forms where
the user fills in the parameters and submits the query.
Version 3.0 provides a content-based event notification
capability. A subscription may be created by a user for receiving a
specific type of event. A registry notifies subscribers of events
matching their subscription by sending a notification to a web service
or an email address end point.
Finally, version 3.0 makes the ebXML Registry even more standards
compliant byaligning with a variety of others standards. These include
Web Services Security: SOAP Message Security 1.0, Web Services Security: SOAP Message with Attachments (SwA) Profile 1.0, WS-I: Basic Security Profile 1.0, and WS-I: Basic Profile 1.1, in addition to SAML 2.0 and XACML 1.0. [Farrukh Najmi is co-editor of the version 3.0 RIM and RS CD level specifications]
