Rich Web Application Backplane Incubator Group Charter

The mission of the Rich Web Application Backplane Incubator Group, part of the Incubator Activity, is to explore and refine the architecture of a "Rich Web Application Backplane" -- a set of common building blocks for web applications.

Join the Rich Web Application Backplane Incubator Group.

End date8 April 2009
ConfidentialityProceedings are public
Initial ChairsCharlie Wiecha, IBM
Initiating Members
Usual Meeting ScheduleTeleconferences: Weekly
Face-to-face: Will be scheduled as required, to be co-located with related Working Group F2F meetings.


We propose that common building blocks such as submission, data models, model-view binding and behavior, and web components can provide a common infrastructure for multiple markup formats. Further, we propose a common infrastructure for both declarative and imperative web programming languages. By aligning APIs and their declarative representations, we hope to support both implementation approaches and increase interoperability between them.

We believe the benefits to end-user interaction of adopting such common infrastructure will include richer user interaction enabled through simplified approaches to mixing multiple interaction technologies in a single application. The ability to easily share data across multiple components, and to freely intermix AJAX and declarative components, should support a wider range of high function composable UIs.


One element of the backplane should be a common approach to "submission" used in multiple Working Groups. In addition, we desire submission to have common behavior across both scripting and declarative programming models. We will explore a common set of events related to the submission lifecycle which can be driven by either script-based or declarative handlers.

Data model

The role of the data model is to serve as a bridge between end-users and the business services with which they interact. An intelligent data model can be seen as a mobile agent that carries with it selected business rules (e.g. bind statements in XForms).

It is important to stress that not all applications may require the full set of function outlined here. We propose a modularized definition of a data model for the Rich Web application backplane that includes the following features:


Within W3C and outside, much use is being made of events and event handling. Specs such as HTML and XForms use events as the hook for adding interactive functionality, and defining the processing model through sequences of events.

Events are important to many groups, especially those related to interactive content. Groups that are clearly involved include: HTML, Forms, SVG, WAI, Voice, SYMM, DI, CDF and Web API. What is needed is a unified approach across W3C, preferably in a generic way so that compound documents can operate in a consistent manner.

Examples of topics that may be addressed in the events area include the following. Members of the XG will set priorities for examining these, and other event-related, issues during initial meetings.

Backplane conformance, reuse, and composition

A key goal of the backplane is to support a loose coupling style of interaction among components. By plugging into the backplane, and listening to and raising data change events on it, web applications might be created with fewer dependencies on the internal design of their embedded components. New controller languages, like the State-Chart XML being defined in the Voice Browser WG, could further simplify the job of responding to events on the backplane and hence help web authoring become possible for increasing numbers of developers.

The Backplane XG will define a high-level architecture describing how the collection of common components identified above can be used together in such a loosely-coupled style. The architecture will include guidance for writing backplane-conforming applications in terms of the modularity of their artifacts -- addressing questions such as what's needed to "include" the backplane, what metadata is required for an application fragment wanting to "plug-in" to the backplane? Finally, we will look at approaches to support packaging backplane based markup fragments into reusable and distributable web components.



We will deliver a set of requirements for the backplane components outlined above to operate with minimal cross-dependence, allowing for flexible composition and subsetting of function. An application which required only subsets of data model function, for example, or data models and submission but no model-view binding could make use of appropriate subsets of backplane function.

We will define requirements to support consistent component behavior (e.g. event lifecycle) whether authored in scripting and declarative programming models.

Draft specs

The main deliverable of the Rich Web Application Backplane XG will be a refined architectural description of the backplane along with proposed refactorings, or extensions, of existing markups to help align them with the backplane.

Proposals for follow-on work

A final deliverable will be a suggested means for continuing the architectural coordination across WG's implicit in the backplane effort so that on-going collaboration can be achieved beyond the time period of this XG.


W3C Groups

Compound Document Formats Working Group
The Backplane Incubator Group cooperates with this group to ensure that backplane deliverables can be readily combined with other W3C specifications. We hope that Backplane results will have impact on multiple existing WG deliverables, which then will be considered by the CDF WG for future profiles.
Ubiquitous Web Applications Working Group
The Backplane Incubator Group coordinates with this group on abstract events and to assure that backplane deliverables meet requirements for device independent access.
Hypertext Coordination Group
The Hypertext Coordination Group has the responsibility for ensuring that reviews between Working Groups are planned and carried out so as to meet requirements for deliverables and deadlines. Many Working Groups related to the Backplane XG fall into the scope of interest of the Hypertext Coordination Group.
Internationalization Core Working Group
The Backplane Incubator Group cooperates with this group to ensure effective support for internationalization.
Multimodal Interaction Working Group
Some backplane-aware applications will, like XForms, separate the user interface, logic and data. The Backplane Incubator Group will collaborate with the Multimodal Working Group to assure any proposed UI layering meets requirements for multimodal interaction.
Scalable Vector Graphics Working Group
The Backplane Incubator Group cooperates with this group to explore common submission, data binding and event-based model-view coordination.
Synchronized Multimedia Working Group
Explore common submission, data binding and event-based model-view coordination
Voice Browser Working Group
The Backplane Incubator Group looks to the VBWG to contribute the State Chart XML language as a Backlane controller component. Also to contribute VoiceXML as a namespace usable as a backplane view. We look to the VBWG to consume a refactored and profiled submission and data model from the Backplane XG.
Web Accessibility Initiative
The Backplane Incubator Group cooperates with the Web Accessibility Initiative (WAI) to ensure meeting W3C accessibility goals.
Web Applications Working Group
The Backplane XG will work with the proposed combined Web Applications Working group to coordinate event and DOM architectures, as well as submission and data model architectures across declarative and script-based programming models.
Web Security Context Working Group
The Backplane Incubator Group will cooperate with the Web Security Context Baseline Working Group, part of the Security Activity, for general security considerations.
XForms Working Group
Contribute starting point for backplane submission, data model, and event-based binding from XForms 1.1 for refactoring into independent backplane components.
XHTML 2 Working Group
The Backplane Incubator Group will cooperates with the XHTML 2 Working Group as XHTML 2 already integrates XForms 1.0 to assure any proposed refactoring of XForms meets XHTML 2 requirements.

External Groups

None initially


Weekly telecons with occasional FtF meetings in conjunction with other WGs.


This group primarily conducts its work on the public mailing list public-xg-app-backplane@w3.org (archive) . The group's Member-only list is member-xg-app-backplane@w3.org (archive)

Information about the group (deliverables, participants, face-to-face meetings, teleconferences, etc.) is available from the Rich Web Application Backplane Incubator Group home page.

Decision Policy

As explained in the Process Document (section 3.3), this group will seek to make decisions when there is consensus. When the Chair puts a question and observes dissent, after due consideration of different opinions, the Chair should record a decision (possibly after a formal vote) and any objections, and move on.

Patent Policy

This Incubator Group provides an opportunity to share perspectives on the topic addressed by this charter. W3C reminds Incubator Group participants of their obligation to comply with patent disclosure obligations as set out in Section 6 of the W3C Patent Policy. While the Incubator Group does not produce Recommendation-track documents, when Incubator Group participants review Recommendation-track specifications from Working Groups, the patent disclosure obligations do apply.

Incubator Groups have as a goal to produce work that can be implemented on a Royalty Free basis, as defined in the W3C Patent Policy.

Participants agree to offer patent licenses according to the W3C Royalty-Free licensing requirements described in Section 5 of the W3C Patent Policy for any portions of the XG Reports produced by this XG that are subsequently incorporated into a W3C Recommendation produced by a Working Group which is chartered to take the XG Report as an input. This licensing commitment may not be revoked but may be modified through the Exclusion process defined in Section 4 of the Patent Policy.

Participants in this Incubator Group wishing to exclude essential patent claims from the licensing commitment must join the Working Group created to work on the XG Report and follow the normal exclusion procedures defined by the Patent Policy. The W3C Team is responsible for notifying all Participants in this Incubator Group in the event that a new Working Group is proposed to develop a Recommendation that takes the XG Report as an input.

For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.

About this Charter

This charter for the Rich Web Application Backplane Incubator Group has been created according to the Incubator Group Procedures documentation. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Charlie Wiecha, IBM

$Date: 2008/04/09 13:03:55 $