Search:

• Login

• RecentChanges
• FindPage
• HelpContents
• WP1.2

• Immutable Page
• Info
• Attachments
• More Actions: Raw Text Print View Render as Docbook Delete Cache ------------ Check Spelling Like Pages Local Site Map ------------ Rename Page Delete Page ------------ My Pages Subscribe User ------------ Remove Spam Package Pages

W1.2 Notification mechanism

General Note

This CWA specified a notification mechanism, based on the descriptions being available in local, decentralised registries and sent to subscribers using content syndication standards, more precisely ATOM and the corresponding ATOM Publication Protocol.

Assessment of available 'subscribe and notify' standards and specifications

Note: This assessment section will probably be either a separate document from the final CWA or an annex in it. It is not suitable for being a normative part of the final specification.

Requirements

• Support for federated registries
• Simple to implement on top of existing implementations
• SOA and ROA compatible

Federation mechanisms in ebXML RS

The ebXML Registry Specification consists by the two sister OASIS standards [OA05a] and [OA05b], the former specifying its internal data model, the latter its SOAP-based API. Its overall scope it is quite similar to registry standards such as UDDI (Universal Description and Universal Description, Discovery and Integration), though it supports more flexible content models. ebXML RS also differs from UDDI in that from version 3.0 onwards it allows for federated queries.

ebxml_rs_federated.pdf ebxml_rs_federated.graffle

Federated queries are propagated from clients through a central node to participating registries, possibly including the clients' credentials. The participating registries then decide autonomously what type of answer they can give, taking the clients' identity into account. The central node then consolidates the answers and sends the compound response back to the querying clients.

The standard specifies the SOAP-based API that is used for queries in general and for federated queries and the corresponding rights management in particular. This API is rather complex, difficult to implement on top of existing registries. It binds participating registries tightly together.

TODO: Refer to ADNOM and WP2

Resource-Oriented Architecture

• RESTful principles
• Role of URIs and in particular PSIs in ROA

Role of Syndication Formats

• ATOM / RSS
• ATOM Publishing Protocol
• GDATA API

XTM and Topic Map Fragments

TODO

Specification of selected mechanism, together with appropriate user documentation

Note: This together with most of W1.3 are probably the parts that are really interesting for implementers. We should position this as part of a multipart CWA with separate conformance clause etc.

Specifies the general mechanism (ATOM + XTM fragments) and thus lies the basis for W1.3